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Gurton WH, King DG, Ranchordas MK, Siegler JC, Gough LA. Enhancing exercise performance and recovery through sodium bicarbonate supplementation: introducing the ingestion recovery framework. Eur J Appl Physiol 2024:10.1007/s00421-024-05578-0. [PMID: 39177769 DOI: 10.1007/s00421-024-05578-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2024] [Accepted: 08/12/2024] [Indexed: 08/24/2024]
Abstract
Sodium bicarbonate (SB) supplementation is an ergogenic strategy for athletes competing in high-intensity exercise, but the efficacy of SB for accelerating recovery from exercise and thus improving performance during repeated bouts of exercise is not fully understood. In a similar fashion to using SB as a pre-exercise buffer, it is possible accelerated restoration of blood pH and bicarbonate following an exercise bout mechanistically underpins the use of SB as a recovery aid. Physiological mechanisms contributing to beneficial effects for SB during repeated bout exercise could be more far-reaching however, as alterations in strong ion difference (SID) and attenuated cellular stress response might also contribute to accelerated recovery from exercise. From inspection of existing literature, ingestion of 0.3 g kg-1 body mass SB ~60-90 min pre-exercise seems to be the most common dosage strategy, but there is evidence emerging for the potential application of post-exercise supplementation timing, gradual SB doses throughout a competition day, or even ingestion during exercise. Based on this review of literature, an SB ingestion recovery framework is proposed to guide athletes and practitioners on the use of SB to enhance performance for multiple bouts of exercise.
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Affiliation(s)
- William H Gurton
- Sport & Physical Activity Research Centre, Sheffield Hallam University, Sheffield, UK
| | - David G King
- School of Energy, Geoscience, Infrastructure and Society, Institute for Life and Earth Sciences, Heriot Watt University, Edinburgh, Scotland, UK
| | - Mayur K Ranchordas
- Sport & Physical Activity Research Centre, Sheffield Hallam University, Sheffield, UK
- Advanced Wellbeing Research Centre, Sheffield, UK
| | - Jason C Siegler
- College of Health Solutions, Arizona State University, Phoenix, AZ, USA
| | - Lewis A Gough
- Human Performance and Health Research Group, Centre for Life & Sport Sciences (CLaSS), Birmingham City University, Birmingham, UK.
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2
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MacDougall KB, Zhang J, Grunau M, Anklovitch E, MacIntosh BR, MacInnis MJ, Aboodarda SJ. Acute performance fatigability following continuous versus intermittent cycling protocols is not proportional to total work done. Appl Physiol Nutr Metab 2024; 49:1055-1067. [PMID: 38631044 DOI: 10.1139/apnm-2023-0503] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/19/2024]
Abstract
Classical training theory postulates that performance fatigability following a training session should be proportional to the total work done (TWD); however, this notion has been questioned. This study investigated indices of performance and perceived fatigability after primary sessions of high-intensity interval training (HIIT) and constant work rate (CWR) cycling, each followed by a cycling time-to-task failure (TTF) bout. On separate days, 16 participants completed an incremental cycling test, and, in a randomized order, (i) a TTF trial at 80% of peak power output (PPO), (ii) an HIIT session, and (iii) a CWR session, both of which were immediately followed by a TTF trial at 80% PPO. Central and peripheral aspects of performance fatigability were measured using interpolated twitch technique, and perceptual measures were assessed prior to and following the HIIT and CWR trials, and again following the TTF trial. Despite TWD being less following HIIT (P = 0.029), subsequent TTF trial was an average of 125 s shorter following HIIT versus CWR (P < 0.001), and this was accompanied by greater impairments in voluntary and electrically evoked forces (P < 0.001), as well as exacerbated perceptual measures (P < 0.001); however, there were no differences in any fatigue measure following the TTF trial (P ≥ 0.149). There were strong correlations between the decline in TTF and indices of peripheral (r = 0.70) and perceived fatigability (r ≥ 0.80) measured at the end of HIIT and CWR. These results underscore the dissociation between TWD and performance fatigability and highlight the importance of peripheral components of fatigability in limiting endurance performance during high-intensity cycling exercise.
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Affiliation(s)
| | - Jenny Zhang
- Faculty of Kinesiology, University of Calgary, Calgary, AB, Canada
| | - Micah Grunau
- Faculty of Kinesiology, University of Calgary, Calgary, AB, Canada
| | - Eric Anklovitch
- Faculty of Kinesiology, University of Calgary, Calgary, AB, Canada
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Ferragut C, Gonzalo-Encabo P, López-Samanes Á, Valadés D, Pérez-López A. Effect of Acute Sodium Bicarbonate and Caffeine Coingestion on Repeated-Sprint Performance in Recreationally Trained Individuals: A Randomized Controlled Trial. Int J Sports Physiol Perform 2024; 19:427-434. [PMID: 38335952 DOI: 10.1123/ijspp.2023-0256] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2023] [Revised: 12/18/2023] [Accepted: 01/08/2024] [Indexed: 02/12/2024]
Abstract
INTRODUCTION The acute and isolated ingestion of sodium bicarbonate (NaHCO3) and caffeine (CAF) improves performance and delays fatigue in high-intensity tasks. However, it remains to be elucidated if the coingestion of both dietary supplements stimulates a summative ergogenic effect. This study aimed to examine the effect of the acute coingestion of NaHCO3 and CAF on repeated-sprint performance. METHODS Twenty-five trained participants (age: 23.3 [4.0] y; sex [female/male]: 12/13; body mass: 69.6 [12.5] kg) participated in a randomized, double-blind, placebo (PLA) -controlled, crossover study. Participants were assigned to 4 conditions: (1) NaHCO3 + CAF, (2) NaHCO3, (3) CAF, or (4) PLA. Thus, they ingested 0.3 g/kg of NaHCO3, 3 mg/kg of CAF, or PLA. Then, participants performed 4 Wingate tests (Wt), consisting of a 30-second all-out sprint against an individualized resisted load, interspersed by a 1.5-minute rest period between sprints. RESULTS Peak (Wpeak) and mean (Wmean) power output revealed a supplement and sprint interaction effect (P = .009 and P = .049, respectively). Compared with PLA, NaHCO3 + CAF and NaHCO3 increased Wpeak performance in Wt 3 (3%, P = .021) and Wt 4 (4.5%, P = .047), while NaHCO3 supplementation increased mean power performance in Wt 3 (4.2%, P = .001). In Wt 1, CAF increased Wpeak (3.2%, P = .054) and reduced time to Wpeak (-8.5%; P = .008). Plasma lactate showed a supplement plus sprint interaction (P < .001) when NaHCO3 was compared with CAF (13%, P = .031) and PLA (23%, P = .021). CONCLUSION To summarize, although the isolated ingestion of CAF and NaHCO3 improved repeated-sprint performance, the coingestion of both supplements did not stimulate a synergic ergogenic effect.
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Affiliation(s)
- Carmen Ferragut
- Departamento de Ciencias Biomédicas, Área de Educación Física y Deportiva, Facultad de Medicina y Ciencias de la Salud, Universidad de Alcalá, Madrid, España
| | - Paola Gonzalo-Encabo
- Departamento de Ciencias Biomédicas, Área de Educación Física y Deportiva, Facultad de Medicina y Ciencias de la Salud, Universidad de Alcalá, Madrid, España
| | - Álvaro López-Samanes
- Education, Research Methods and Evaluation Department, Faculty of Human and Social Sciences, Universidad Pontificia Comillas, Madrid, Spain
| | - David Valadés
- Departamento de Ciencias Biomédicas, Área de Educación Física y Deportiva, Facultad de Medicina y Ciencias de la Salud, Universidad de Alcalá, Madrid, España
| | - Alberto Pérez-López
- Departamento de Ciencias Biomédicas, Área de Educación Física y Deportiva, Facultad de Medicina y Ciencias de la Salud, Universidad de Alcalá, Madrid, España
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Zagatto AM, Lopes VHF, Dutra YM, de Poli RAB, Dolan E, Rasica L, Murias JM, de Azevedo PHSM. Sodium bicarbonate induces alkalosis, but improves high-intensity cycling performance only when participants expect a beneficial effect: a placebo and nocebo study. Eur J Appl Physiol 2024; 124:1367-1380. [PMID: 38032386 DOI: 10.1007/s00421-023-05368-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2023] [Accepted: 10/31/2023] [Indexed: 12/01/2023]
Abstract
The study aimed to investigate the effects of sodium bicarbonate (NaHCO3) intake with divergent verbal and visual information on constant load cycling time-to-task failure, conducted within the severe intensity domain. Fifteen recreational cyclists participated in a randomized double-blind, crossover study, ingesting NaHCO3 or placebo (i.e., dextrose), but with divergent information about its likely influence (i.e., likely to induce ergogenic, inert, or harmful effects). Performance was evaluated using constant load cycling time to task failure trial at 115% of peak power output estimated during a ramp incremental exercise test. Data on blood lactate, blood acid-base balance, muscle electrical activity (EMG) through electromyography signal, and the twitch interpolation technique to assess neuromuscular indices were collected. Despite reduced peak force in the isometric maximal voluntary contraction and post-effort peripheral fatigue in all conditions (P < 0.001), neither time to task failure, EMG nor, blood acid-base balance differed between conditions (P > 0.05). Evaluation of effect sizes of all conditions suggested that informing participants that the supplement would be likely to have a positive effect (NaHCO3/Ergogenic: 0.46; 0.15-0.74; Dextrose/Ergogenic: 0.45; 0.04-0.88) resulted in improved performance compared to control. Thus, NaHCO3 ingestion consistently induced alkalosis, indicating that the physiological conditions to improve performance were present. Despite this, NaHCO3 ingestion did not influence performance or indicators of neuromuscular fatigue. In contrast, effect size estimates indicate that participants performed better when informed that they were ingesting an ergogenic supplement. These findings suggest that the apparently ergogenic effect of NaHCO3 may be due, at least in part, to a placebo effect.
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Affiliation(s)
- Alessandro Moura Zagatto
- Laboratory of Physiology and Sport Performance (LAFIDE), Department of Physical Education, School of Sciences, São Paulo State University (UNESP), Post-Graduate Program in Movement Sciences, Av. Eng. Luiz Edmundo Carrijo Coube, 14-01, Vargem Limpa, Bauru, SP, CEP 17033-360, Brazil.
| | - Vithor Hugo Fialho Lopes
- Laboratory of Physiology and Sport Performance (LAFIDE), Department of Physical Education, School of Sciences, São Paulo State University (UNESP), Post-Graduate Program in Movement Sciences, Av. Eng. Luiz Edmundo Carrijo Coube, 14-01, Vargem Limpa, Bauru, SP, CEP 17033-360, Brazil
| | - Yago Medeiros Dutra
- Laboratory of Physiology and Sport Performance (LAFIDE), Department of Physical Education, School of Sciences, São Paulo State University (UNESP), Post-Graduate Program in Movement Sciences, Av. Eng. Luiz Edmundo Carrijo Coube, 14-01, Vargem Limpa, Bauru, SP, CEP 17033-360, Brazil
| | - Rodrigo Araujo Bonetti de Poli
- Laboratory of Physiology and Sport Performance (LAFIDE), Department of Physical Education, School of Sciences, São Paulo State University (UNESP), Post-Graduate Program in Movement Sciences, Av. Eng. Luiz Edmundo Carrijo Coube, 14-01, Vargem Limpa, Bauru, SP, CEP 17033-360, Brazil
| | - Eimear Dolan
- Applied Physiology and Nutrition Research Group, Center of Lifestyle Medicine, Faculdade de Medicina FMUSP, Universidade de São Paulo, São Paulo, Brazil
| | - Letizia Rasica
- Faculty of Kinesiology, Human Performance Lab, University of Calgary, Calgary, Canada
| | - Juan M Murias
- College of Health and Life Sciences, Hamad Bin Khalifa University, Doha, Qatar
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Morton-Jones ME, Gladden LB, Kavazis AN, Sandage MJ. A Tutorial on Skeletal Muscle Metabolism and the Role of Blood Lactate: Implications for Speech Production. JOURNAL OF SPEECH, LANGUAGE, AND HEARING RESEARCH : JSLHR 2024; 67:369-383. [PMID: 38157288 DOI: 10.1044/2023_jslhr-23-00531] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/03/2024]
Abstract
PURPOSE The purpose of this tutorial is threefold: (a) present relevant exercise science literature on skeletal muscle metabolism and synthesize the limited available research on metabolism of the adult human speech musculature in an effort to elucidate the role of metabolism in speech production; (b) introduce a well-studied metabolic serum biomarker in exercise science, lactate, and the potential usefulness of investigating this metabolite, through a well-established exercise science methodology, to better understand metabolism of the musculature involved in voice production; and (c) discuss exercise physiology considerations for future voice science research that seeks to investigate blood lactate and metabolism in voice physiology in an ecologically valid manner. METHOD This tutorial begins with relevant exercise science literature on the basic cellular processes of muscle contraction that require energy and the metabolic mechanisms that regenerate the energy required for task execution. The tutorial next synthesizes the available research investigating metabolism of the adult human speech musculature. This is followed by the authors proposing a hypothesis of speech metabolism based on the voice science literature and the application of well-studied exercise science principles of muscle physiology. The tutorial concludes with a discussion and the potential usefulness of lactate in investigations to better understand the metabolism of the musculature involved in vocal demand tasks. CONCLUSION The role of metabolism during speech (respiratory, laryngeal, and articulatory) is an understudied yet critical aspect of speech physiology that warrants further study to better understand the metabolic systems that are used to meet vocal demands.
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Affiliation(s)
| | | | | | - Mary J Sandage
- Department of Speech, Language, and Hearing Sciences, Auburn University, AL
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Rodrigues JFC, Mendes TT, Gomes PF, Silami-Garcia E, Amorim FT, Sevilio MNO, Rossi FE, Wanner SP. Reduced running performance and greater perceived exertion, but similar post-exercise neuromuscular fatigue in tropical natives subjected to a 10 km self-paced run in a hot compared to a temperate environment. PLoS One 2023; 18:e0290081. [PMID: 37590220 PMCID: PMC10434900 DOI: 10.1371/journal.pone.0290081] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2023] [Accepted: 08/01/2023] [Indexed: 08/19/2023] Open
Abstract
Environmental heat stress impairs endurance performance by enhancing exercise-induced physiological and perceptual responses. However, the time course of these responses during self-paced running, particularly when comparing hot and temperate conditions, still needs further clarification. Moreover, monitoring fatigue induced by exercise is paramount to prescribing training and recovery adequately, but investigations on the effects of a hot environment on post-exercise neuromuscular fatigue are scarce. This study compared the time course of physiological and perceptual responses during a 10 km self-paced treadmill run (as fast as possible) between temperate (25°C) and hot (35°C) conditions. We also investigated the changes in countermovement jump (CMJ) performance following exercise in these two ambient temperatures. Thirteen recreational long-distance runners (11 men and 2 women), inhabitants of a tropical region, completed the two experimental trials in a randomized order. Compared to 25°C, participants had transiently higher body core temperature (TCORE) and consistently greater perceived exertion while running at 35°C (p < 0.05). These changes were associated with a slower pace, evidenced by an additional 14 ± 5 min (mean ± SD) to complete the 10 km at 35°C than at 25°C (p < 0.05). Before, immediately after, and 1 h after the self-paced run, the participants performed CMJs to evaluate lower limb neuromuscular fatigue. CMJ height was reduced by 7.0% (2.3 ± 2.4 cm) at 1 h after the race (p < 0.05) compared to pre-exercise values; environmental conditions did not influence this reduction. In conclusion, despite the reduced endurance performance, higher perceived exertion, and transiently augmented TCORE caused by environmental heat stress, post-exercise neuromuscular fatigue is similar between temperate and hot conditions. This finding suggests that the higher external load (faster speed) at 25°C compensates for the effects of more significant perceptual responses at 35°C in inducing neuromuscular fatigue.
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Affiliation(s)
- Jefferson F. C. Rodrigues
- Exercise Physiology Laboratory, School of Physical Education, Physiotherapy and Occupational Therapy, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brazil
| | - Thiago T. Mendes
- Department of Physical Education, Faculty of Education, Universidade Federal da Bahia, Salvador, Bahia, Brazil
| | - Patrícia F. Gomes
- Exercise Physiology Laboratory, School of Physical Education, Physiotherapy and Occupational Therapy, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brazil
| | - Emerson Silami-Garcia
- Exercise Physiology Laboratory, School of Physical Education, Physiotherapy and Occupational Therapy, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brazil
- Department of Sports, School of Physical Education, Physiotherapy and Occupational Therapy, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brazil
| | - Fabiano T. Amorim
- Department of Health, Exercise and Sports Sciences, University of New Mexico, Albuquerque, New Mexico, United States of America
| | - Mário N. O. Sevilio
- Health Sciences Center, Universidade Federal do Maranhão, São Luís, Maranhão, Brazil
| | - Fabrício E. Rossi
- Immunometabolism of Skeletal Muscle and Exercise Research Group and Laboratory of Muscle Performance, Department of Physical Education, Universidade Federal do Piauí, Teresina, Piauí, Brazil
- Graduate Program in Science and Health, Universidade Federal do Piauí, Teresina, Piauí, Brazil
| | - Samuel P. Wanner
- Exercise Physiology Laboratory, School of Physical Education, Physiotherapy and Occupational Therapy, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brazil
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Gurton WH, Matta GG, Gough LA, Ranchordas MK, King DG, Hurst P. Sodium Bicarbonate and Time-to-Exhaustion Cycling Performance: A Retrospective Analysis Exploring the Mediating Role of Expectation. SPORTS MEDICINE - OPEN 2023; 9:65. [PMID: 37523028 PMCID: PMC10390418 DOI: 10.1186/s40798-023-00612-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/21/2022] [Accepted: 07/12/2023] [Indexed: 08/01/2023]
Abstract
BACKGROUND Research has shown that ingesting 0.3 g·kg-1 body mass sodium bicarbonate (NaHCO3) can improve time-to-exhaustion (TTE) cycling performance, but the influence of psychophysiological mechanisms on ergogenic effects is not yet understood. OBJECTIVE This study retrospectively examined whether changes in TTE cycling performance are mediated by positive expectations of receiving NaHCO3 and/or the decline in blood bicarbonate during exercise. METHODS In a randomised, crossover, counterbalanced, double-blind, placebo-controlled design, 12 recreationally trained cyclists (maximal oxygen consumption, 54.4 ± 5.7 mL·kg·min-1) performed four TTE cycling tests 90 min after consuming: (1) 0.3 g·kg-1 body mass NaHCO3 in 5 mL·kg-1 body mass solution, (2) 0.03 g·kg-1 body mass sodium chloride in solution (placebo), (3) 0.3 g·kg-1 body mass NaHCO3 in capsules and (4) cornflour in capsules (placebo). Prior to exercise, participants rated on 1-5 Likert type scales how much they expected the treatment they believe had been given would improve performance. Capillary blood samples were measured for acid-base balance at baseline, pre-exercise and post-exercise. RESULTS Administering NaHCO3 in solution and capsules improved TTE compared with their respective placebos (solution: 27.0 ± 21.9 s, p = 0.001; capsules: 23.0 ± 28.1 s, p = 0.016). Compared to capsules, NaHCO3 administered via solution resulted in a higher expectancy about the benefits on TTE cycling performance (Median: 3.5 vs. 2.5, Z = 2.135, p = 0.033). Decline in blood bicarbonate during exercise was higher for NaHCO3 given in solution compared to capsules (2.7 ± 2.1 mmol·L-1, p = 0.001). Mediation analyses showed that improvements in TTE cycling were indirectly related to expectancy and decline in blood bicarbonate when NaHCO3 was administered in solution but not capsules. CONCLUSIONS Participants' higher expectations when NaHCO3 is administered in solution could result in them exerting themselves harder during TTE cycling, which subsequently leads to a greater decline in blood bicarbonate and larger improvements in performance. KEY POINTS Ingesting 0.3 g·kg-1 body mass sodium bicarbonate in solution and capsules improved time-to-exhaustion cycling performance Positive expectancy about the benefits of sodium bicarbonate and decline in blood bicarbonate were higher when sodium bicarbonate was administered in solution compared with capsules Improvements in time-to-exhaustion cycling performance for sodium bicarbonate administered in solution were related to expectancy and the enhanced extracellular buffering response.
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Affiliation(s)
- William H Gurton
- School of Psychology and Life Sciences, Canterbury Christ Church University, Canterbury, UK
- Sport and Physical Activity Research Centre, College of Health, Wellbeing and Life Sciences, Sheffield Hallam University, Sheffield, UK
| | - Guilherme G Matta
- School of Psychology and Life Sciences, Canterbury Christ Church University, Canterbury, UK
| | - Lewis Anthony Gough
- Human Performance and Health Research Group, Centre for Life and Sport Sciences, Birmingham City University, Birmingham, UK
| | - Mayur Krachna Ranchordas
- Sport and Physical Activity Research Centre, College of Health, Wellbeing and Life Sciences, Sheffield Hallam University, Sheffield, UK.
| | - David G King
- School of Biosciences and Medicine, University of Surrey, Guildford, UK
| | - Philip Hurst
- School of Psychology and Life Sciences, Canterbury Christ Church University, Canterbury, UK
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Chang TC, Chen WC, Huang CW, Lin LC, Lin JS, Cheng FY. Anti-fatigue activity of dripped spent hens chicken essence in ICR mice. Anim Biosci 2023; 36:307-314. [PMID: 36108702 PMCID: PMC9834736 DOI: 10.5713/ab.22.0172] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2022] [Accepted: 07/04/2022] [Indexed: 12/24/2022] Open
Abstract
OBJECTIVE Chicken essence and branched chain amino acid (BCAA) supplementation has been recognized to significantly relieve fatigue. To obtain chicken essence with high amounts of BCAA, spent hens herein was used to prepare dripped chicken essence (SCE) and compared with commercial dripped chicken essence (CCE) for in vivo anti-fatigue effect. METHODS To determine the effect on anti-fatigue by dripped chicken essence, the exhaustive swimming was performed. Thirty-two 7-week ICR mice were divided into four groups, which included the control group (CG), CCE, SCE-1X and SCE-2X. The mice were given daily oral administration (0.012 mL/g body weight/d). The fatigue index analysis was conducted weekly. RESULTS The results showed that SCE had a higher BCAA level as expected, and mice treated with dripped chicken essence (CCE and SCE) could significantly improve exercise performance. The lower blood lactate level, blood urea nitrogen level and creatine phosphokinase activity were found in the supplement of SCE group compared with the CCE group, which suggested that the SCE possessed strong anti-fatigue ability. This could possibly be due to the higher content of BCAA. CONCLUSION In this study, SCE promoted recovery from physical fatigue in mice and elevated endurance ability. Among them, the double dose (SCE-2X) showed the strongest anti-fatigue ability. Taken together, spent chickens could be a good source of chicken essence to improve the effect of anti-fatigue.
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Affiliation(s)
- Ti Chun Chang
- Department of Food Science, National Pingtung University of Science and Technology, Pingtung 912301,
Taiwan
| | - Wei Cheng Chen
- Department of Biomechatronics Engineering, National Pingtung University of Science and Technology, Pingtung 912301,
Taiwan
| | - Chao Wei Huang
- Department of Tropical Agriculture and International Cooperation, National Pingtung University of Science and Technology, Pingtung 912301,
Taiwan
| | - Liang Chuan Lin
- Department of Animal Science, National Chung Hsin University, Taichung 40227,
Taiwan
| | - Jen Shinn Lin
- Department of Food Science, National Pingtung University of Science and Technology, Pingtung 912301,
Taiwan
| | - Fu Yuan Cheng
- Department of Animal Science, National Pingtung University of Science and Technology, Pingtung 912301,
Taiwan,Corresponding Author: Fu Yuan Cheng, Tel: +886-8-7703202#6203, Fax: +886-8-7740148, E-mail:
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Che K, Yang Y, Zhang J, Feng L, Xie Y, Li Q, Qiu J. Oral pyruvate prevents high-intensity interval exercise-induced metabolic acidosis in rats by promoting lactate dehydrogenase reaction. Front Nutr 2023; 10:1096986. [PMID: 37090767 PMCID: PMC10117856 DOI: 10.3389/fnut.2023.1096986] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2022] [Accepted: 03/20/2023] [Indexed: 04/25/2023] Open
Abstract
Introduction There is no denying the clinical benefits of exogenous pyruvate in the treatment of pathological metabolic acidosis. However, whether it can prevent exercise physiological metabolic acidosis, delay the occurrence of exercise fatigue, and improve the beneficial effects of exercise and its internal mechanism remain unclear. Methods We randomly divided 24 male SD rats into 3 groups: one group was a control without exercise (CC, n = 8), and the other two groups were supplemented with 616 mg/kg/day pyruvate (EP, n = 8) or distilled water of equal volume (EC, n = 8). These groups completed acute high-intensity interval exercise (HIIE) after 7 days of supplementation. The acid metabolism variables were measured immediately after exercise including blood pH (pHe), base excess (BE), HCO3 -, blood lactic acid and skeletal muscle pH (pHi). The redox state was determined by measuring the oxidized coenzyme I/reduced coenzyme I (nicotinamide adenine dinucleotide [NAD+]/reduced NAD+ [NADH]) ratio and lactate/pyruvate (L/P) ratio. In addition, the activities of lactate dehydrogenase A (LDHA), hexokinase (HK), phosphofructokinase (PFK) and pyruvate kinase (PK) were determined by ELISA. Results Pyruvate supplementation significantly reversed the decrease of pHe, BE, HCO3 - and pHi values after HIIE (p < 0.001), while significantly increased the activities of LDHA (p = 0.048), HK (p = 0.006), and PFK (p = 0.047). Compared with the CC, the NAD+/NADH (p = 0.008) ratio and the activities of LDHA (p = 0.002), HK (p < 0.001), PFK (p < 0.001), and PK (p = 0.006) were significantly improved in EP group. Discussion This study provides compelling evidence that oral pyruvate attenuates HIIE-induced intracellular and extracellular acidification, possibly due to increased activity of LDHA, which promotes the absorption of H+ in the LDH reaction. The beneficial effects of improving the redox state and glycolysis rate were also shown. Our results suggest that pyruvate can be used as an oral nutritional supplement to buffer HIIE induced metabolic acidosis.
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Affiliation(s)
- Kaixuan Che
- Department of Exercise Biochemistry, Exercise Science School, Beijing Sport University, Beijing, China
| | - Yanping Yang
- Department of Exercise Biochemistry, Exercise Science School, Beijing Sport University, Beijing, China
| | - Jun Zhang
- Department of Exercise Biochemistry, Exercise Science School, Beijing Sport University, Beijing, China
| | - Lin Feng
- Department of Exercise Biochemistry, Exercise Science School, Beijing Sport University, Beijing, China
| | - Yan Xie
- Department of Exercise Biochemistry, Exercise Science School, Beijing Sport University, Beijing, China
| | - Qinlong Li
- Department of Exercise Physiology, Exercise Science School, Beijing Sport University, Beijing, China
| | - Junqiang Qiu
- Department of Exercise Biochemistry, Exercise Science School, Beijing Sport University, Beijing, China
- Beijing Sports Nutrition Engineering Research Center, Beijing, China
- *Correspondence: Junqiang Qiu,
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A Comparison of Sodium Citrate and Sodium Bicarbonate Ingestion: Blood Alkalosis and Gastrointestinal Symptoms. Int J Sport Nutr Exerc Metab 2023; 33:1-10. [PMID: 36109008 DOI: 10.1123/ijsnem.2022-0083] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2022] [Revised: 07/21/2022] [Accepted: 07/26/2022] [Indexed: 12/30/2022]
Abstract
This study compared the recommended dose of sodium citrate (SC, 500 mg/kg body mass) and sodium bicarbonate (SB, 300 mg/kg body mass) for blood alkalosis (blood [HCO3-]) and gastrointestinal symptoms (GIS; number and severity). Sixteen healthy individuals ingested the supplements in a randomized, crossover design. Gelatin capsules were ingested over 15 min alongside a carbohydrate-rich meal, after which participants remained seated for forearm venous blood sample collection and completion of GIS questionnaires every 30 min for 300 min. Time-course and session value (i.e., peak and time to peak) comparisons of SC and SB supplementation were performed using linear mixed models. Peak blood [HCO3-] was similar for SC (mean 34.2, 95% confidence intervals [33.4, 35.0] mmol/L) and SB (mean 33.6, 95% confidence intervals [32.8, 34.5] mmol/L, p = .308), as was delta blood [HCO3-] (SC = 7.9 mmol/L; SB = 7.3 mmol/L, p = .478). Blood [HCO3-] was ≥6 mmol/L above baseline from 180 to 240 min postingestion for SC, significantly later than for SB (120-180 min; p < .001). GIS were mostly minor, and peaked 80-90 min postingestion for SC, and 35-50 min postingestion for SB. There were no significant differences for the number or severity of GIS reported (p > .05 for all parameters). In summary, the recommended doses of SC and SB induce similar blood alkalosis and GIS, but with a different time course.
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11
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Gough LA, Williams JJ, Newbury JW, Gurton WH. The effects of sodium bicarbonate supplementation at individual time-to-peak blood bicarbonate on 4-km cycling time trial performance in the heat. Eur J Sport Sci 2022; 22:1856-1864. [PMID: 34704539 DOI: 10.1080/17461391.2021.1998644] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
The purpose of this study was to explore the effect of individualised sodium bicarbonate (NaHCO3) supplementation according to a pre-established individual time-to-peak (TTP) blood bicarbonate (HCO3-) on 4-km cycling time trial (TT) performance in the heat. Eleven recreationally trained male cyclists (age: 28 ± 6 years, height: 180 ± 6 cm, body mass: 80.5 ± 8.4 kg) volunteered for this study in a randomised, crossover, triple-blind, placebo-controlled design. An initial visit was conducted to determine TTP HCO3- following 0.2 g.kg-1 body mass (BM) NaHCO3 ingestion. Subsequently, on three separate occasions, participants completed a 4-km cycling TT in the heat (30 degrees centigrade; °C) (relative humidity ∼40%) following ingestion of either NaHCO3 (0.2 g.kg-1 body mass), a sodium chloride placebo (0.2 g.kg-1 BM; PLA) at the predetermined individual TTP HCO3-, or no supplementation (control; CON) . Absolute peak [HCO3-] prior to the 4-km cycling TT's was elevated for NaHCO3 compared to PLA (+2.8 mmol.l-1; p = 0.002; g = 2.2) and CON (+2.5 mmol.l-1; p < 0.001; g = 2.1). Completion time following NaHCO3 was 5.6 ± 3.2 s faster than PLA (1.6%; CI: 2.8, 8.3; p = 0.001; g = 0.2) and 4.7 ± 2.8 s faster than CON (1.3%; CI: 2.3, 7.1; p = 0.001; g = 0.2). These results demonstrate that NaHCO3 ingestion at a pre-established individual TTP HCO3- improves 4-km cycling TT performance in the heat, likely through enhancing buffering capacity.Highlights This is the first time NaHCO3 ingestion has been shown to improve 4-km cycling TT performance in conditions of high ambient heat.A smaller dose of NaHCO3 (0.2 g.kg-1 BM) is ergogenic in the heat, which is smaller than the dose typically ingested for sports performance (0.3 g.kg-1 BM). This is important, as gastrointestinal discomfort is typically lower as the dose reduces.This study suggests that the individualised time-to-peak HCO3- ingestion strategy with lower doses of NaHCO3 is an ergogenic strategy in conditions of high ambient heat.
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Affiliation(s)
- Lewis A Gough
- Human Performance and Health Research Group, Centre for Life and Sport Sciences Research Centre, Birmingham City University, Birmingham, UK
| | - Jake J Williams
- Human Performance and Health Research Group, Centre for Life and Sport Sciences Research Centre, Birmingham City University, Birmingham, UK
| | - Josh W Newbury
- Human Performance and Health Research Group, Centre for Life and Sport Sciences Research Centre, Birmingham City University, Birmingham, UK
| | - William H Gurton
- Department of Sport, Exercise and Rehabilitation Sciences, Canterbury Christ Church University, Canterbury, UK
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12
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Zoladz JA, Majerczak J, Galganski L, Grandys M, Zapart-Bukowska J, Kuczek P, Kołodziejski L, Walkowicz L, Szymoniak-Chochół D, Kilarski W, Jarmuszkiewicz W. Endurance Training Increases the Running Performance of Untrained Men without Changing the Mitochondrial Volume Density in the Gastrocnemius Muscle. Int J Mol Sci 2022; 23:ijms231810843. [PMID: 36142755 PMCID: PMC9503714 DOI: 10.3390/ijms231810843] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2022] [Revised: 09/15/2022] [Accepted: 09/15/2022] [Indexed: 11/16/2022] Open
Abstract
The activity and quantity of mitochondrial proteins and the mitochondrial volume density (MitoVD) are higher in trained muscles; however, the underlying mechanisms remain unclear. Our goal was to determine if 20 weeks’ endurance training simultaneously increases running performance, the amount and activity of mitochondrial proteins, and MitoVD in the gastrocnemius muscle in humans. Eight healthy, untrained young men completed a 20-week moderate-intensity running training program. The training increased the mean speed of a 1500 m run by 14.0% (p = 0.008) and the running speed at 85% of maximal heart rate by 9.6% (p = 0.008). In the gastrocnemius muscle, training significantly increased mitochondrial dynamics markers, i.e., peroxisome proliferator-activated receptor gamma coactivator 1-alpha (PGC-1α) by 23%, mitochondrial transcription factor A (TFAM) by 29%, optic artrophy-1 (OPA1) by 31% and mitochondrial fission factor (MFF) by 44%, and voltage-dependent anion channel 1 (VDAC1) by 30%. Furthermore, training increased the amount and maximal activity of citrate synthase (CS) by 10% and 65%, respectively, and the amount and maximal activity of cytochrome c oxidase (COX) by 57% and 42%, respectively, but had no effect on the total MitoVD in the gastrocnemius muscle. We concluded that not MitoVD per se, but mitochondrial COX activity (reflecting oxidative phosphorylation activity), should be regarded as a biomarker of muscle adaptation to endurance training in beginner runners.
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Affiliation(s)
- Jerzy A. Zoladz
- Chair of Exercise Physiology and Muscle Bioenergetics, Faculty of Health Sciences, Jagiellonian University Medical College, Skawinska 8, 31-066 Krakow, Poland
- Correspondence:
| | - Joanna Majerczak
- Chair of Exercise Physiology and Muscle Bioenergetics, Faculty of Health Sciences, Jagiellonian University Medical College, Skawinska 8, 31-066 Krakow, Poland
| | - Lukasz Galganski
- Laboratory of Mitochondrial Biochemistry, Department of Bioenergetics, Faculty of Biology, Adam Mickiewicz University, Uniwersytetu Poznańskiego 6, 61-614 Poznan, Poland
| | - Marcin Grandys
- Chair of Exercise Physiology and Muscle Bioenergetics, Faculty of Health Sciences, Jagiellonian University Medical College, Skawinska 8, 31-066 Krakow, Poland
| | - Justyna Zapart-Bukowska
- Chair of Exercise Physiology and Muscle Bioenergetics, Faculty of Health Sciences, Jagiellonian University Medical College, Skawinska 8, 31-066 Krakow, Poland
| | - Piotr Kuczek
- Department of Physical Education, Faculty of Health Sciences, University of Applied Sciences in Tarnow, Mickiewicza 8, 33-110 Tarnow, Poland
| | - Leszek Kołodziejski
- Department of Nursing, Faculty of Health Sciences, University of Applied Sciences in Tarnow, Mickiewicza 8, 33-110 Tarnow, Poland
| | - Lucyna Walkowicz
- Chair of Exercise Physiology and Muscle Bioenergetics, Faculty of Health Sciences, Jagiellonian University Medical College, Skawinska 8, 31-066 Krakow, Poland
| | | | | | - Wieslawa Jarmuszkiewicz
- Laboratory of Mitochondrial Biochemistry, Department of Bioenergetics, Faculty of Biology, Adam Mickiewicz University, Uniwersytetu Poznańskiego 6, 61-614 Poznan, Poland
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13
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Paris MT, McNeil CJ, Power GA, Rice CL, Dalton BH. Age-related performance fatigability: a comprehensive review of dynamic tasks. J Appl Physiol (1985) 2022; 133:850-866. [PMID: 35952347 DOI: 10.1152/japplphysiol.00319.2022] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Adult ageing is associated with a myriad of changes within the neuromuscular system, leading to reductions in contractile function of old adults. One of the consequences of these age-related neuromuscular adaptations is altered performance fatigability, which can limit the ability of old adults to perform activities of daily living. Whereas age-related fatigability of isometric tasks has been well characterized, considerably less is known about fatigability of old adults during dynamic tasks involving movement about a joint, which provides a more functionally relevant task compared to static contractions. This review provides a comprehensive summary of age-related fatigability in dynamic contractions, where the importance of task specificity is highlighted with a brief discussion of the potential mechanisms responsible for differences in fatigability between young and old adults. The angular velocity of the task is critical for evaluating age-related fatigability, as tasks which constrain angular velocity (i.e., isokinetic) produce equivocal age-related differences in fatigability, whereas tasks involving unconstrained velocity (i.e., isotonic-like) consistently induce greater fatigability of old compared to young adults. These unconstrained velocity tasks, that are more closely associated with natural movements, offer an excellent model to uncover the underlying age-related mechanisms of increased fatigability. Future work evaluating the mechanisms of increased age-related fatigability of dynamic tasks should be evaluated using task-specific contractions (i.e., dynamic), particularly for assessment of spinal and supra-spinal components. Advancing our understanding of age-related fatigability is likely to yield novel insights and approaches for improving mobility limitations in old adults.
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Affiliation(s)
- Michael T Paris
- School of Kinesiology, University of Western Ontario, London, ON, Canada
| | - Chris J McNeil
- School of Health and Exercise Science, University of British Columbia, Kelowna, BC, Canada
| | - Geoffrey A Power
- Department of Human Health and Nutritional Sciences, University of Guelph, Guelph, ON, Canada
| | - Charles L Rice
- School of Kinesiology, University of Western Ontario, London, ON, Canada.,Department of Anatomy and Cell Biology, University of Western Ontario, London, ON, Canada
| | - Brian H Dalton
- School of Health and Exercise Science, University of British Columbia, Kelowna, BC, Canada
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14
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Negro M, Cerullo G, Perna S, Beretta-Piccoli M, Rondanelli M, Liguori G, Cena H, Phillips SM, Cescon C, D’Antona G. Effects of a Single Dose of a Creatine-Based Multi-Ingredient Pre-workout Supplement Compared to Creatine Alone on Performance Fatigability After Resistance Exercise: A Double-Blind Crossover Design Study. Front Nutr 2022; 9:887523. [PMID: 35799580 PMCID: PMC9255897 DOI: 10.3389/fnut.2022.887523] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2022] [Accepted: 04/28/2022] [Indexed: 11/25/2022] Open
Abstract
Background This study aims to investigate the acute effects of a single oral administration of a creatine-based multi-ingredient pre-workout supplement (MIPS) on performance fatigability and maximal force production after a resistance exercise protocol (REP). Methods Eighteen adult males (age: 23 ± 1 years; body mass: 76.4 ± 1.5 kg; height: 1.77 ± 0.01 m) were enrolled in a randomized, double-blind, crossover design study. Subjects received a single dose of a MIPS (3 g of creatine, 2 g of arginine, 1 g of glutamine, 1 g of taurine, and 800 mg of β-alanine) or creatine citrate (CC) (3 g of creatine) or a placebo (PLA) in three successive trials 1 week apart. In a randomized order, participants consumed either MIPS, CC, or PLA and performed a REP 2 h later. Before ingestion and immediately after REP, subjects performed isometric contractions of the dominant biceps brachii: two maximal voluntary contractions (MVCs), followed by a 20% MVC for 90 s and a 60% MVC until exhaustion. Surface electromyographic indices of performance fatigability, conduction velocity (CV), and fractal dimension (FD) were obtained from the surface electromyographic signal (sEMG). Time to perform the task (TtT), basal blood lactate (BL), and BL after REP were also measured. Results Following REP, statistically significant (P < 0.05) pre–post mean for ΔTtT between MIPS (−7.06 s) and PLA (+0.222 s), ΔCV slopes (20% MVC) between MIPS (0.0082%) and PLA (−0.0519%) and for ΔCV slopes (60% MVC) between MIPS (0.199%) and PLA (−0.154%) were found. A pairwise comparison analysis showed no statistically significant differences in other variables between groups and condition vs. condition. Conclusion After REP, a creatine-enriched MIPS resulted in greater improvement of sEMG descriptors of performance fatigability and TtT compared with PLA. Conversely, no statistically significant differences in outcomes measured were observed between CC and PLA or MIPS and CC.
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Affiliation(s)
- Massimo Negro
- Centro di Ricerca Interdipartimentale nelle Attività Motorie e Sportive (CRIAMS) – Sport Medicine Centre, University of Pavia, Voghera, Italy
| | - Giuseppe Cerullo
- Department of Movement Sciences and Wellbeing, University of Naples Parthenope, Naples, Italy
| | - Simone Perna
- Department of Biology, College of Science, University of Bahrain, Sakhir, Bahrain
| | - Matteo Beretta-Piccoli
- Rehabilitation Research Laboratory 2rLab, Department of Business Economics, Health and Social Care, University of Applied Sciences and Arts of Southern Switzerland, Manno, Switzerland
| | - Mariangela Rondanelli
- Department of Public Health, Experimental and Forensic Medicine, University of Pavia, Pavia, Italy
- Istituto di Ricovero e Cura a Carattere Scientifico (IRCCS) Mondino Foundation, Pavia, Italy
| | - Giorgio Liguori
- Department of Movement Sciences and Wellbeing, University of Naples Parthenope, Naples, Italy
| | - Hellas Cena
- Department of Public Health, Experimental and Forensic Medicine, University of Pavia, Pavia, Italy
- Clinical Nutrition and Dietetics Service, Unit of Internal Medicine and Endocrinology, Istituti Clinici Scientifici (ICS) Maugeri Istituto di Ricovero e Cura a Carattere Scientifico (IRCCS), University of Pavia, Pavia, Italy
| | - Stuart M. Phillips
- Exercise Metabolism Research Group, Department of Kinesiology, McMaster University, Hamilton, ON, Canada
| | - Corrado Cescon
- Rehabilitation Research Laboratory 2rLab, Department of Business Economics, Health and Social Care, University of Applied Sciences and Arts of Southern Switzerland, Manno, Switzerland
| | - Giuseppe D’Antona
- Centro di Ricerca Interdipartimentale nelle Attività Motorie e Sportive (CRIAMS) – Sport Medicine Centre, University of Pavia, Voghera, Italy
- Department of Public Health, Experimental and Forensic Medicine, University of Pavia, Pavia, Italy
- *Correspondence: Giuseppe D’Antona,
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15
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Albanese GA, Falzarano V, Holmes MWR, Morasso P, Zenzeri J. A Dynamic Submaximal Fatigue Protocol Alters Wrist Biomechanical Properties and Proprioception. Front Hum Neurosci 2022; 16:887270. [PMID: 35712530 PMCID: PMC9196583 DOI: 10.3389/fnhum.2022.887270] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2022] [Accepted: 05/11/2022] [Indexed: 11/13/2022] Open
Abstract
Fatigue is a temporary condition that arises as a result of intense and/or prolonged use of muscles and can affect skilled human performance. Therefore, the quantitative analysis of these effects is a topic of crucial interest in both ergonomics and clinical settings. This study introduced a novel protocol, based on robotic techniques, to quantitatively assess the effects of fatigue on the human wrist joint. A wrist manipulandum was used for two concurrent purposes: (1) implementing the fatigue task and (2) assessing the functional changes both before and at four time points after the end of the fatigue task. Fourteen participants completed the experimental protocol, which included the fatigue task and assessment sessions over 2 days. Specifically, the assessments performed are related to the following indicators: (1) isometric forces, (2) biomechanical properties of the wrist, (3) position sense, and (4) stretch reflexes of the muscles involved. The proposed fatigue task was a short-term, submaximal and dynamic wrist flexion/extension task designed with a torque opposing wrist flexion. A novel task termination criterion was employed and based on a percentage decrease in the mean frequency of muscles measured using surface electromyography. The muscle fatigue analysis demonstrated a change in mean frequency for both the wrist flexors and extensors, however, only the isometric flexion force decreased 4 min after the end of the task. At the same time point, wrist position sense was significantly improved and stiffness was the lowest. Viscosity presented different behaviors depending on the direction evaluated. At the end of the experiment (about 12 min after the end of the fatigue task), wrist position sense recovered to pre-fatigue values, while biomechanical properties did not return to their pre-fatigue values. Due to the wide variety of fatigue tasks proposed in the literature, it has been difficult to define a complete framework that presents the dynamic of fatigue-related changes in different components associated with wrist function. This work enables us to discuss the possible causes and the mutual relationship of the changes detected after the same task.
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Affiliation(s)
- Giulia A. Albanese
- Department of Robotics, Brain and Cognitive Sciences, Istituto Italiano di Tecnologia, Genova, Italy
- Department of Informatics, Bioengineering, Robotics and Systems Engineering (DIBRIS), University of Genoa, Genoa, Italy
- *Correspondence: Giulia A. Albanese,
| | - Valeria Falzarano
- Department of Robotics, Brain and Cognitive Sciences, Istituto Italiano di Tecnologia, Genova, Italy
- Department of Informatics, Bioengineering, Robotics and Systems Engineering (DIBRIS), University of Genoa, Genoa, Italy
| | - Michael W. R. Holmes
- Faculty of Applied Health Sciences, Brock University, St. Catharines, ON, Canada
| | - Pietro Morasso
- Department of Robotics, Brain and Cognitive Sciences, Istituto Italiano di Tecnologia, Genova, Italy
| | - Jacopo Zenzeri
- Department of Robotics, Brain and Cognitive Sciences, Istituto Italiano di Tecnologia, Genova, Italy
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16
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Hureau TJ, Broxterman RM, Weavil JC, Lewis MT, Layec G, Amann M. On the role of skeletal muscle acidosis and inorganic phosphates as determinants of central and peripheral fatigue: A 31 P-MRS study. J Physiol 2022; 600:3069-3081. [PMID: 35593645 DOI: 10.1113/jp283036] [Citation(s) in RCA: 23] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2022] [Accepted: 04/28/2022] [Indexed: 01/20/2023] Open
Abstract
Intramuscular hydrogen ion (H+ ) and inorganic phosphate (Pi) concentrations were dissociated during exercise to challenge their relationships with peripheral and central fatigue in vivo. Ten recreationally active, healthy men (27 ± 5 years; 180 ± 4 cm; 76 ± 10 kg) performed two consecutive intermittent isometric single-leg knee-extensor trials (60 maximal voluntary contractions; 3 s contraction, 2 s relaxation) interspersed with 5 min of rest. Phosphorus magnetic resonance spectroscopy (31 P-MRS) was used to continuously quantify intramuscular [H+ ] and [Pi] during both trials. Using electrical femoral nerve stimulation, quadriceps twitch force (Qtw ) and voluntary activation (VA) were quantified at rest and throughout both trials. Decreases in Qtw and VA from baseline were used to determine peripheral and central fatigue, respectively. Qtw was strongly related to both [H+ ] (β coefficient: -0.9, P < 0.0001) and [Pi] (-1.1, P < 0.0001) across trials. There was an effect of trial on the relationship between Qtw and [H+ ] (-0.5, P < 0.0001), but not Qtw and [Pi] (0.0, P = 0.976). This suggests that, unlike the unaltered association with [Pi], a given level of peripheral fatigue was associated with a different [H+ ] in Trial 1 vs. Trial 2. VA was related to [H+ ] (-0.3, P < 0.0001), but not [Pi] (-0.2, P = 0.243), across trials and there was no effect of trial (-0.1, P = 0.483). Taken together, these results support intramuscular Pi as a primary cause of peripheral fatigue, and muscle acidosis, probably acting on group III/IV muscle afferents in the interstitial space, as a contributor to central fatigue during exercise. KEY POINTS: We investigated the relationship between intramuscular metabolites and neuromuscular function in humans performing two maximal, intermittent, knee-extension trials interspersed with 5 min of rest. Concomitant measurements of intramuscular hydrogen (H+ ) and inorganic phosphate (Pi) concentrations, as well as quadriceps twitch-force (Qtw ) and voluntary activation (VA), were made throughout each trial using phosphorus magnetic resonance spectroscopy (31 P-MRS) and electrical femoral nerve stimulations. Although [Pi] fully recovered prior to the onset of the second trial, [H+ ] did not. Qtw was strongly related to both [H+ ] and [Pi] across both trials. However, the relationship between Qtw and [H+ ] shifted leftward from the first to the second trial, whereas the relationship between Qtw and [Pi] remained unaltered. VA was related to [H+ ], but not [Pi], across both trials. These in vivo findings support the hypotheses of intramuscular Pi as a primary cause of peripheral fatigue, and muscle acidosis, probably acting on group III/IV muscle afferents, as a contributor to central fatigue.
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Affiliation(s)
- Thomas J Hureau
- Department of Medicine, University of Utah, Salt Lake City, UT, USA.,University of Strasbourg, Faculty of Sport Sciences, UR 3072: Mitochondria, Oxidative Stress and Muscular Protection Laboratory, Strasbourg, France
| | - Ryan M Broxterman
- Department of Medicine, University of Utah, Salt Lake City, UT, USA.,Geriatric Research, Education, and Clinical Center, Salt Lake City, UT, VAMC, USA
| | - Joshua C Weavil
- Department of Medicine, University of Utah, Salt Lake City, UT, USA.,Geriatric Research, Education, and Clinical Center, Salt Lake City, UT, VAMC, USA
| | - Matthew T Lewis
- Department of Medicine, University of Utah, Salt Lake City, UT, USA.,Geriatric Research, Education, and Clinical Center, Salt Lake City, UT, VAMC, USA
| | - Gwenael Layec
- Department of Medicine, University of Utah, Salt Lake City, UT, USA
| | - Markus Amann
- Department of Medicine, University of Utah, Salt Lake City, UT, USA.,Geriatric Research, Education, and Clinical Center, Salt Lake City, UT, VAMC, USA.,Department of Anesthesiology, University of Utah, Salt Lake City, UT, USA
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Martínez-Noguera FJ, Alcaraz PE, Carlos-Vivas J, Marín-Pagán C. Chronic Supplementation of 2S-Hesperidin Improves Acid-Base Status and Decreases Lactate at FatMax, at Ventilatory Threshold 1 and 2 and after an Incremental Test in Amateur Cyclists. BIOLOGY 2022; 11:biology11050736. [PMID: 35625464 PMCID: PMC9138540 DOI: 10.3390/biology11050736] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/18/2022] [Revised: 04/29/2022] [Accepted: 05/06/2022] [Indexed: 11/30/2022]
Abstract
Simple Summary Currently, hesperidin is a molecule found mainly in citrus fruits and is being widely researched in the area of chronic disease, but also in the field of sports nutrition. Some studies have shown its antioxidant, anti-inflammatory, lipid and carbohydrate metabolism modulating effects, including the enhancement of nitric oxide synthesis. However, few human studies have demonstrated a positive effect of hesperidin intake, in particular 2S-hesperidin, on sports performance, particularly in anaerobic and aerobic tests. However, the biochemical mechanisms that may be responsible for this enhanced performance have not yet been described. Therefore, one of the aims of this study was to assess whether an eight-week intake of 2S-hesperidin can improve acid-base status and metabolic status (lactate and glucose) in an incremental test in amateur cyclists. The results showed that amateur cyclists chronically supplemented with 2S-hesperidin improved acid-base status and lactate at FatMax, ventilatory thresholds 1 and 2, and in the acute phase of recovery after maximal effort. Abstract Chronic supplementation with 2S-hesperidin improves performance; however, the mechanisms underlying this effect have not yet been explored. Therefore, the aim of this study was to assess whether changes in acid-base status may be associated with improved performance after 2S-hesperidin supplementation compared to microcellulose (placebo). Forty amateur cyclists (n = 20 per group) underwent a rectangular test where capillary blood samples were taken at baseline, FatMax1, VT1, VT2, PMAX, FatMax2 and EPOC to measure acid-base parameters. After eight weeks of 2S-hesperidin supplementation (500 mg/d) increased HCO3−, SBC, ABE (p ≤ 0.05) and decreased Lac were found at FatMax1, VT1, FatMax2 and EPOC (p ≤ 0.05), while decreased Lac at VT2 was found with a large effect size (ES = 1.15) compared to placebo. Significant group differences in the area under the curve were observed when comparing pre-post-intervention pH changes (p = 0.02) between groups. Chronic supplementation with 2S-hesperidin improved acid-base status and Lac, both at low-moderate and submaximal intensities, improving recovery after exercise-to-exhaustion in amateur cyclists.
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Affiliation(s)
- Francisco Javier Martínez-Noguera
- Research Center for High Performance Sport, Catholic University of Murcia (UCAM), Campus de los Jerónimos Nº 135, 30107 Murcia, Spain; (P.E.A.); (C.M.-P.)
- Correspondence: ; Tel.: +34-968-278-566
| | - Pedro E. Alcaraz
- Research Center for High Performance Sport, Catholic University of Murcia (UCAM), Campus de los Jerónimos Nº 135, 30107 Murcia, Spain; (P.E.A.); (C.M.-P.)
| | - Jorge Carlos-Vivas
- Health, Economy, Motricity and Education Research Group (HEME), Faculty of Sport Sciences, University of Extremadura, Avda. de Elvas, s/n., 06006 Badajoz, Spain;
| | - Cristian Marín-Pagán
- Research Center for High Performance Sport, Catholic University of Murcia (UCAM), Campus de los Jerónimos Nº 135, 30107 Murcia, Spain; (P.E.A.); (C.M.-P.)
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18
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Hebisz RG, Hebisz P, Zatoń MW. Heart Rate Variability After Sprint Interval Training in Cyclists and Implications for Assessing Physical Fatigue. J Strength Cond Res 2022; 36:558-564. [PMID: 32304516 PMCID: PMC8785771 DOI: 10.1519/jsc.0000000000003549] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/02/2022]
Abstract
ABSTRACT Hebisz, RG, Hebisz, P, and Zatoń, MW. Heart rate variability after sprint interval training in cyclists and implications for assessing physical fatigue. J Strength Cond Res 36(2): 558-564, 2022-This study evaluated the time- and frequency-domain indexes of heart rate variability (HRV) during sprint interval exercise test (SIXT) and identify the onset of fatigue by HRV concurrent with changes in average (Pavg) and peak (Ppeak) power output, total oxygen uptake (V̇o2tou), and blood hydrogen (H+) and lactate (La-) concentrations. Twenty-seven cyclists performed 4 sets of SIXT in which each set consisted of four 30-second maximal sprints interspersed with 90 seconds of low-intensity cycling. Each set was separated by 25-40 minutes of recovery. Before beginning each set, HRV was analyzed by time (mean normal-to-normal RR intervals [RRNN], SD of normal-to-normal RR intervals [SDNN], and square root of the mean squared difference between successive normal-to-normal RR intervals [RMSSD]) and frequency (total spectral power [T] and very low- [VLF], low- [LF], and high-frequency [HF] spectral power) domain methods. Pavg, Ppeak, and V̇o2tou were recorded in each set, and H+ and La- were measured after each set. RRNN, SDNN, and VLF decreased in the second set, whereas all time and frequency indexes of HRV decreased in the third and fourth set. Pavg and H+ decreased, while V̇o2tou increased in the fourth set. Ppeak decreased in the second, third, and fourth set. Correlations were found between the changes in the time and frequency indexes of HRV with H+, La-, and V̇o2tou. The results indicate that HRV does not reflect the onset of physical fatigue in SIXT as was observed in Pavg and no correlation was found between the changes in HRV with Pavg and Ppeak.
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Affiliation(s)
- Rafał G Hebisz
- Department of Physiology and Biochemistry, University School of Physical Education, Wroclaw, Poland
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Lower Muscle and Blood Lactate Accumulation in Sickle Cell Trait Carriers in Response to Short High-Intensity Exercise. Nutrients 2022; 14:nu14030501. [PMID: 35276859 PMCID: PMC8838817 DOI: 10.3390/nu14030501] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2021] [Revised: 01/17/2022] [Accepted: 01/18/2022] [Indexed: 12/24/2022] Open
Abstract
It remains unclear whether sickle cell trait (SCT) should be considered a risk factor during intense physical activity. By triggering the polymerization-sickling-vaso-occlusion cascade, lactate accumulation-associated acidosis in response to high-intensity exercise is believed to be one of the causes of complications. However, our understanding of lactate metabolism in response to high-intensity exercise in SCT carriers is incomplete. Thirty male SCT carriers (n = 15) and healthy subjects (n = 15) with and without α-thalassemia performed a 2-min high-intensity exercise. Blood and muscle lactate concentrations were measured at exercise completion. Time courses of blood lactate and glucose concentrations were followed during the subsequent recovery. Additional biochemical analyses were performed on biopsies of the vastus lateralis muscle. SCT was associated with lower blood and muscle lactate concentrations in response to the short high-intensity exercise. Compared to controls, the muscle content among SCT carriers of lactate transporter MCT4 and β2-adrenergic receptor were higher and lower, respectively. During recovery, the lactate removal ability was higher in SCT carriers. In the present study, no effect of α-thalassemia was observed. The lower blood and muscle lactate accumulations in SCT carriers may, to some extent, act as protective mechanisms: (i) against exercise-related acidosis and subsequent sickling, that may explain the relatively rare complications observed in exercising SCT carriers; and (ii) against the deleterious effects of intracellular lactate and associated acidosis on muscle function, that might explain the elevated presence of SCT carriers among the best sprinters.
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“Food First but Not Always Food Only”: Recommendations for Using Dietary Supplements in Sport. Int J Sport Nutr Exerc Metab 2022; 32:371-386. [DOI: 10.1123/ijsnem.2021-0335] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2021] [Revised: 01/31/2022] [Accepted: 01/31/2022] [Indexed: 11/18/2022]
Abstract
The term “food first” has been widely accepted as the preferred strategy within sport nutrition, although there is no agreed definition of this and often limited consideration of the implications. We propose that food first should mean “where practically possible, nutrient provision should come from whole foods and drinks rather than from isolated food components or dietary supplements.” There are many reasons to commend a food first strategy, including the risk of supplement contamination resulting in anti-doping violations. However, a few supplements can enhance health and/or performance, and therefore a food only approach could be inappropriate. We propose six reasons why a food only approach may not always be optimal for athletes: (a) some nutrients are difficult to obtain in sufficient quantities in the diet, or may require excessive energy intake and/or consumption of other nutrients; (b) some nutrients are abundant only in foods athletes do not eat/like; (c) the nutrient content of some foods with established ergogenic benefits is highly variable; (d) concentrated doses of some nutrients are required to correct deficiencies and/or promote immune tolerance; (e) some foods may be difficult to consume immediately before, during or immediately after exercise; and (f) tested supplements could help where there are concerns about food hygiene or contamination. In these situations, it is acceptable for the athlete to consider sports supplements providing that a comprehensive risk minimization strategy is implemented. As a consequence, it is important to stress that the correct terminology should be “food first but not always food only.”
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Markov A, Chaabene H, Hauser L, Behm S, Bloch W, Puta C, Granacher U. Acute Effects of Aerobic Exercise on Muscle Strength and Power in Trained Male Individuals: A Systematic Review with Meta-analysis. Sports Med 2021; 52:1385-1398. [PMID: 34878640 PMCID: PMC9124655 DOI: 10.1007/s40279-021-01615-6] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/26/2021] [Indexed: 12/23/2022]
Abstract
BACKGROUND Concurrent training can be an effective and time-efficient method to improve both muscle strength and aerobic capacity. A major challenge with concurrent training is how to adequately combine and sequence strength exercise and aerobic exercise to avoid interference effects. This is particularly relevant for athletes. OBJECTIVE We aimed to examine the acute effects of aerobic exercise on subsequent measures of muscle strength and power in trained male individuals. DESIGN We performed a systematic review with meta-analysis. DATA SOURCES Systematic literature searches in the electronic databases PubMed, Web of Science, and Google Scholar were conducted up to July 2021. ELIGIBILITY CRITERIA FOR SELECTING STUDIES Studies were included that applied a within-group repeated-measures design and examined the acute effects of aerobic exercise (i.e., running, cycling exercise) on subsequent measures of lower limb muscle strength (e.g., maximal isometric force of the knee extensors) and/or proxies of lower limb muscle power (e.g., countermovement jump height) in trained individuals. RESULTS Fifteen studies met the inclusion criteria. Aerobic exercise resulted in moderate declines in muscle strength (standardized mean difference [SMD] = 0.79; p = 0.003). Low-intensity aerobic exercise did not moderate effects on muscle strength (SMD = 0.65; p = 0.157) while moderate-to-high intensity aerobic exercise resulted in moderate declines in muscle strength (SMD = 0.65; p = 0.020). However, the difference between subgroups was not statistically significant (p = 0.979). Regarding aerobic exercise duration, large declines in muscle strength were found after > 30 min (SMD = 1.02; p = 0.049) while ≤ 30 min of aerobic exercise induced moderate declines in muscle strength (SMD = 0.59; p = 0.013). The subgroup difference was not statistically significant (p = 0.204). Cycling exercise resulted in significantly larger decrements in muscle strength (SMD = 0.79; p = 0.002) compared with running (SMD = 0.28; p = 0.035). The difference between subgroups was statistically significant (p < 0.0001). For muscle power, aerobic exercise did not result in any statistically significant changes (SMD = 0.04; p = 0.846). CONCLUSIONS Aerobic exercise induced moderate declines in measures of muscle strength with no statistically significant effects on proxies of muscle power in trained male individuals. It appears that higher compared with lower intensity as well as longer compared with shorter aerobic exercise duration exacerbate acute declines in muscle strength. Our results provide evidence for acute interference effects when aerobic exercies is performed before strength exercises. These findings may help practitioners to better prescribe single training sessions, particularly if environmental and/or infrastructural reasons (e.g., availability of training facilities) do not allow the application of strength training before aerobic exercise.
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Affiliation(s)
- Adrian Markov
- Division of Training and Movement Sciences, Research Focus Cognition Sciences, Faculty of Human Sciences, University of Potsdam, Am Neuen Palais 10, Bldg. 12, 14469, Potsdam, Germany
| | - Helmi Chaabene
- Faculty of Human Sciences, University of Potsdam, Potsdam, Germany
| | - Lukas Hauser
- Division of Training and Movement Sciences, Research Focus Cognition Sciences, Faculty of Human Sciences, University of Potsdam, Am Neuen Palais 10, Bldg. 12, 14469, Potsdam, Germany
| | - Sebastian Behm
- Division of Training and Movement Sciences, Research Focus Cognition Sciences, Faculty of Human Sciences, University of Potsdam, Am Neuen Palais 10, Bldg. 12, 14469, Potsdam, Germany
| | - Wilhelm Bloch
- Department of Molecular and Cellular Sport Medicine, German Sport University, Cologne, Germany
| | - Christian Puta
- Department of Sports Medicine and Health Promotion, Friedrich-Schiller-University Jena, Jena, Germany
| | - Urs Granacher
- Division of Training and Movement Sciences, Research Focus Cognition Sciences, Faculty of Human Sciences, University of Potsdam, Am Neuen Palais 10, Bldg. 12, 14469, Potsdam, Germany.
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22
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Effects of sodium bicarbonate supplementation on exercise performance: an umbrella review. J Int Soc Sports Nutr 2021; 18:71. [PMID: 34794476 PMCID: PMC8600864 DOI: 10.1186/s12970-021-00469-7] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2021] [Accepted: 11/03/2021] [Indexed: 01/08/2023] Open
Abstract
Background We aimed to perform an umbrella review of meta-analyses examining the effects of sodium bicarbonate supplementation on exercise performance. Methods We systematically searched for meta-analyses that examined the effects of sodium bicarbonate supplementation on exercise performance. The methodological quality of the included reviews was evaluated using the Assessing the Methodological Quality of Systematic Reviews 2 (AMSTAR 2) checklist. Grading of Recommendations Assessment, Development, and Evaluation (GRADE) framework for downgrading the certainty in evidence was used, which included assessments of risk of bias, inconsistency, indirectness, imprecision, and publication bias. Results Eight reviews of moderate and high methodological quality met inclusion criteria. Using the GRADE framework, evidence for the ergogenic effects of sodium bicarbonate supplementation on peak and mean power in the Wingate test and Yo-Yo test performance was classified as being of moderate quality. The evidence for these outcomes did not receive a point on the indirectness GRADE item, as “serious indirectness” was detected. Low-quality evidence was found for the ergogenic effect of sodium bicarbonate supplementation on endurance events lasting ∼45 s to 8 min, muscle endurance, and 2000-m rowing performance. Evidence for these outcomes was classified as low quality, given that risk of bias, indirectness, and publication bias were assessed as “unclear”, “serious”, and “strongly suspected”, respectively. The ergogenic effects ranged from trivial (pooled effect size: 0.09) to large (pooled effect size: 1.26). Still, for most outcomes, sodium bicarbonate elicited comparable ergogenic effects. For example, sodium bicarbonate produced similar effects on performance in endurance events lasting ∼45 s to 8 min, muscle endurance tests, and Yo-Yo test (pooled effect size range: 0.36 to 0.40). No significant differences between the effects of sodium bicarbonate and placebo were found for general mean power, muscle strength, and repeated-sprint ability. Conclusion Based on meta-analyses of moderate to high quality, it can be concluded that sodium bicarbonate supplementation acutely enhances peak anaerobic power, anaerobic capacity, performance in endurance events lasting ∼45 s to 8 min, muscle endurance, 2000-m rowing performance, and high-intensity intermittent running. More research is needed among women to improve the generalizability of findings.
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Kataoka R, Vasenina E, Hammert WB, Ibrahim AH, Dankel SJ, Buckner SL. Is there Evidence for the Suggestion that Fatigue Accumulates Following Resistance Exercise? Sports Med 2021; 52:25-36. [PMID: 34613589 DOI: 10.1007/s40279-021-01572-0] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/18/2021] [Indexed: 12/28/2022]
Abstract
It has been suggested that improper post-exercise recovery or improper sequence of training may result in an 'accumulation' of fatigue. Despite this suggestion, there is a lack of clarity regarding which physiological mechanisms may be proposed to contribute to fatigue accumulation. The present paper explores the time course of the changes in various fatigue-related measures in order to understand how they may accumulate or lessen over time following an exercise bout or in the context of an exercise program. Regarding peripheral fatigue, the depletion of energy substrates and accumulation of metabolic byproducts has been demonstrated to occur following an acute bout of resistance training; however, peripheral accumulation and depletion appear unlikely candidates to accumulate over time. A number of mechanisms may contribute to the development of central fatigue, postulating the need for prolonged periods of recovery; however, a time course is difficult to determine and is dependent on which measurement is examined. In addition, it has not been demonstrated that central fatigue measures accumulate over time. A potential candidate that may be interpreted as accumulated fatigue is muscle damage, which shares similar characteristics (i.e., prolonged strength loss). Due to the delayed appearance of muscle damage, it may be interpreted as accumulated fatigue. Overall, evidence for the presence of fatigue accumulation with resistance training is equivocal, making it difficult to draw the conclusion that fatigue accumulates. Considerable work remains as to whether fatigue can accumulate over time. Future studies are warranted to elucidate potential mechanisms underlying the concept of fatigue accumulation.
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Affiliation(s)
- Ryo Kataoka
- USF Muscle Lab, Exercise Science Program, University of South Florida, 4202 E. Fowler Ave. PED 214, Tampa, FL, 33620-8600, USA
| | - Ecaterina Vasenina
- USF Muscle Lab, Exercise Science Program, University of South Florida, 4202 E. Fowler Ave. PED 214, Tampa, FL, 33620-8600, USA
| | - William B Hammert
- USF Muscle Lab, Exercise Science Program, University of South Florida, 4202 E. Fowler Ave. PED 214, Tampa, FL, 33620-8600, USA
| | - Adam H Ibrahim
- USF Muscle Lab, Exercise Science Program, University of South Florida, 4202 E. Fowler Ave. PED 214, Tampa, FL, 33620-8600, USA
| | - Scott J Dankel
- Exercise Physiology Laboratory, Department of Health and Exercise Science, Rowan University, Glassboro, NJ, USA
| | - Samuel L Buckner
- USF Muscle Lab, Exercise Science Program, University of South Florida, 4202 E. Fowler Ave. PED 214, Tampa, FL, 33620-8600, USA.
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24
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Grgic J, Pedisic Z, Saunders B, Artioli GG, Schoenfeld BJ, McKenna MJ, Bishop DJ, Kreider RB, Stout JR, Kalman DS, Arent SM, VanDusseldorp TA, Lopez HL, Ziegenfuss TN, Burke LM, Antonio J, Campbell BI. International Society of Sports Nutrition position stand: sodium bicarbonate and exercise performance. J Int Soc Sports Nutr 2021; 18:61. [PMID: 34503527 PMCID: PMC8427947 DOI: 10.1186/s12970-021-00458-w] [Citation(s) in RCA: 30] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2021] [Accepted: 08/17/2021] [Indexed: 02/07/2023] Open
Abstract
Based on a comprehensive review and critical analysis of the literature regarding the effects of sodium bicarbonate supplementation on exercise performance, conducted by experts in the field and selected members of the International Society of Sports Nutrition (ISSN), the following conclusions represent the official Position of the Society: 1. Supplementation with sodium bicarbonate (doses from 0.2 to 0.5 g/kg) improves performance in muscular endurance activities, various combat sports, including boxing, judo, karate, taekwondo, and wrestling, and in high-intensity cycling, running, swimming, and rowing. The ergogenic effects of sodium bicarbonate are mostly established for exercise tasks of high-intensity that last between 30 s and 12 min. 2. Sodium bicarbonate improves performance in single- and multiple-bout exercise. 3. Sodium bicarbonate improves exercise performance in both men and women. 4. For single-dose supplementation protocols, 0.2 g/kg of sodium bicarbonate seems to be the minimum dose required to experience improvements in exercise performance. The optimal dose of sodium bicarbonate dose for ergogenic effects seems to be 0.3 g/kg. Higher doses (e.g., 0.4 or 0.5 g/kg) may not be required in single-dose supplementation protocols, because they do not provide additional benefits (compared with 0.3 g/kg) and are associated with a higher incidence and severity of adverse side-effects. 5. For single-dose supplementation protocols, the recommended timing of sodium bicarbonate ingestion is between 60 and 180 min before exercise or competition. 6. Multiple-day protocols of sodium bicarbonate supplementation can be effective in improving exercise performance. The duration of these protocols is generally between 3 and 7 days before the exercise test, and a total sodium bicarbonate dose of 0.4 or 0.5 g/kg per day produces ergogenic effects. The total daily dose is commonly divided into smaller doses, ingested at multiple points throughout the day (e.g., 0.1 to 0.2 g/kg of sodium bicarbonate consumed at breakfast, lunch, and dinner). The benefit of multiple-day protocols is that they could help reduce the risk of sodium bicarbonate-induced side-effects on the day of competition. 7. Long-term use of sodium bicarbonate (e.g., before every exercise training session) may enhance training adaptations, such as increased time to fatigue and power output. 8. The most common side-effects of sodium bicarbonate supplementation are bloating, nausea, vomiting, and abdominal pain. The incidence and severity of side-effects vary between and within individuals, but it is generally low. Nonetheless, these side-effects following sodium bicarbonate supplementation may negatively impact exercise performance. Ingesting sodium bicarbonate (i) in smaller doses (e.g., 0.2 g/kg or 0.3 g/kg), (ii) around 180 min before exercise or adjusting the timing according to individual responses to side-effects, (iii) alongside a high-carbohydrate meal, and (iv) in enteric-coated capsules are possible strategies to minimize the likelihood and severity of these side-effects. 9. Combining sodium bicarbonate with creatine or beta-alanine may produce additive effects on exercise performance. It is unclear whether combining sodium bicarbonate with caffeine or nitrates produces additive benefits. 10. Sodium bicarbonate improves exercise performance primarily due to a range of its physiological effects. Still, a portion of the ergogenic effect of sodium bicarbonate seems to be placebo-driven.
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Affiliation(s)
- Jozo Grgic
- Institute for Health and Sport, Victoria University, Melbourne, Australia.
| | - Zeljko Pedisic
- Institute for Health and Sport, Victoria University, Melbourne, Australia
| | - Bryan Saunders
- Applied Physiology and Nutrition Research Group, School of Physical Education and Sport; Rheumatology Division; Faculdade de Medicina FMUSP, Universidade de Sao Paulo, Sao Paulo, SP, BR, University of São Paulo, Sao Paulo, Brazil
- Institute of Orthopaedics and Traumatology, Faculty of Medicine FMUSP, University of São Paulo, Sao Paulo, Brazil
| | - Guilherme G Artioli
- Centre for Bioscience, Manchester Metropolitan University, Manchester, M1 5GD, UK
| | | | - Michael J McKenna
- Institute for Health and Sport, Victoria University, Melbourne, Australia
| | - David J Bishop
- Institute for Health and Sport, Victoria University, Melbourne, Australia
| | - Richard B Kreider
- Exercise & Sport Nutrition Lab, Human Clinical Research Facility, Department of Health & Kinesiology, Texas A&M University, College Station, TX, USA
| | - Jeffrey R Stout
- Physiology of Work and Exercise Response (POWER) Laboratory, Institute of Exercise Physiology and Rehabilitation Science, School of Kinesiology and Physical Therapy, University of Central Florida, Orlando, FL, USA
| | - Douglas S Kalman
- Nutrion Department, College of Osteopathic Medicine, Nova Southeastern University, Fort Lauderdale, FL, 33314, USA
- Scientific Affairs. Nutrasource, Guelph, ON, Canada
| | - Shawn M Arent
- Department of Exercise Science, Arnold School of Public Health, University of South Carolina, Columbia, SC, USA
| | - Trisha A VanDusseldorp
- Department of Exercise Science and Sport Management, Kennesaw State University, Kennesaw, GA, USA
| | - Hector L Lopez
- The Center for Applied Health Sciences, Stow, OH, USA
- Supplement Safety Solutions, Bedford, MA, 01730, USA
| | | | - Louise M Burke
- Exercise and Nutrition Research Program, Mary MacKillop Institute for Health Research, Australian Catholic University, Melbourne, Australia
| | - Jose Antonio
- Exercise and Sport Science, Nova Southeastern University, Davie, FL, 33314, USA
| | - Bill I Campbell
- Performance & Physique Enhancement Laboratory, University of South Florida, Tampa, FL, 33612, USA
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Warm-Up Intensity Does Not Affect the Ergogenic Effect of Sodium Bicarbonate in Adult Men. Int J Sport Nutr Exerc Metab 2021; 31:482-489. [PMID: 34480008 DOI: 10.1123/ijsnem.2021-0076] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2021] [Revised: 07/07/2021] [Accepted: 07/07/2021] [Indexed: 11/18/2022]
Abstract
This study determined the influence of a high- (HI) versus low-intensity (LI) cycling warm-up on blood acid-base responses and exercise capacity following ingestion of sodium bicarbonate (SB; 0.3 g/kg body mass) or a placebo (PLA; maltodextrin) 3 hr prior to warm-up. Twelve men (21 ± 2 years, 79.2 ± 3.6 kg body mass, and maximum power output [Wmax] 318 ± 36 W) completed a familiarization and four double-blind trials in a counterbalanced order: HI warm-up with SB, HI warm-up with PLA, LI warm-up with SB, and LI warm-up with PLA. LI warm-up was 15 min at 60% Wmax, while the HI warm-up (typical of elites) featured LI followed by 2 × 30 s (3-min break) at Wmax, finishing 30 min prior to a cycling capacity test at 110% Wmax. Blood bicarbonate and lactate were measured throughout. SB supplementation increased blood bicarbonate (+6.4 mmol/L; 95% confidence interval, CI [5.7, 7.1]) prior to greater reductions with HI warm-up (-3.8 mmol/L; 95% CI [-5.8, -1.8]). However, during the 30-min recovery, blood bicarbonate rebounded and increased in all conditions, with concentrations ∼5.3 mmol/L greater with SB supplementation (p < .001). Blood bicarbonate significantly declined during the cycling capacity test at 110%Wmax with greater reductions following SB supplementation (-2.4 mmol/L; 95% CI [-3.8, -0.90]). Aligned with these results, SB supplementation increased total work done during the cycling capacity test at 110% Wmax (+8.5 kJ; 95% CI [3.6, 13.4], ∼19% increase) with no significant main effect of warm-up intensity (+0.0 kJ; 95% CI [-5.0, 5.0]). Collectively, the results demonstrate that SB supplementation can improve HI cycling capacity irrespective of prior warm-up intensity, likely due to blood alkalosis.
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Sara LK, Gutsch SB, Hunter SK. The single-leg heel raise does not predict maximal plantar flexion strength in healthy males and females. PLoS One 2021; 16:e0253276. [PMID: 34415915 PMCID: PMC8378718 DOI: 10.1371/journal.pone.0253276] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2020] [Accepted: 06/01/2021] [Indexed: 12/04/2022] Open
Abstract
Introduction The single-leg heel raise test (SLHR) is commonly used in clinical settings to approximate plantar flexor strength, yet this is neither validated nor supported physiologically. The purposes of this study were to: determine (1) associations between SLHR repetitions, maximal plantar flexor strength, and reductions in strength; and (2) whether sex differences exist in performance of the SLHR. Methods Twenty-eight young, healthy participants (14 males,14 females, 19–30 years) performed repeated single-leg heel raises to task failure. Pre- and post-task measures included maximal voluntary isometric contractions (MVIC), and voluntary activation and contractile properties of the plantar flexor muscles, assessed using peripheral electrical stimulation of the tibial nerve. Surface electromyography was recorded for the medial and lateral gastrocnemius, soleus, and anterior tibialis muscles. Results The SLHR resulted in 20.5% reductions in MVIC torque (p<0.001). However, the number of SLHR repetitions was not correlated with either the baseline MVIC (maximal strength; p = 0.979) or the reduction in MVIC following the SLHR (p = 0.23). There were no sex differences in either the number of SLHR repetitions (p = 0.14), baseline MVIC torque (p = 0.198), or the reduction of MVIC (p = 0.14). MVIC decline was positively associated with the reduction in voluntary activation (r = 0.841, p<0.001), but was not associated with the change in twitch amplitude (p = 0.597). Conclusions The SLHR was similar in young males and females yet was a poor predictor of maximal plantar flexor strength but evaluates performance fatigability of the lower extremity specific to dynamic contractions. The reduction in maximal strength at task failure was explained by reduced neural drive to the plantar flexor muscles in both males and females. Impact statement SLHR performance is not a clinical assessment of plantar flexor strength but assesses dynamic lower extremity fatigability that is similar in males and females. Alternate clinical measures for maximal plantar flexion strength need to be developed.
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Affiliation(s)
- Lauren K. Sara
- Department of Physical Therapy, Marquette University, Milwaukee, Wisconsin, United States of America
- * E-mail:
| | - Savannah B. Gutsch
- Department of Physical Therapy, Marquette University, Milwaukee, Wisconsin, United States of America
| | - Sandra K. Hunter
- Department of Physical Therapy, Marquette University, Milwaukee, Wisconsin, United States of America
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Øvretveit K, Laginestra FG. Mechanisms and Trainability of Peripheral Fatigue in Grappling. Strength Cond J 2021. [DOI: 10.1519/ssc.0000000000000594] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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28
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Newbury JW, Cole M, Kelly AL, Chessor RJ, Sparks SA, McNaughton LR, Gough LA. The time to peak blood bicarbonate (HCO3-), pH, and the strong ion difference (SID) following sodium bicarbonate (NaHCO3) ingestion in highly trained adolescent swimmers. PLoS One 2021; 16:e0248456. [PMID: 34197456 PMCID: PMC8248647 DOI: 10.1371/journal.pone.0248456] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2021] [Accepted: 06/17/2021] [Indexed: 11/18/2022] Open
Abstract
The timing of sodium bicarbonate (NaHCO3) supplementation has been suggested to be most optimal when coincided with a personal time that bicarbonate (HCO3–) or pH peaks in the blood following ingestion. However, the ergogenic mechanisms supporting this ingestion strategy are strongly contested. It is therefore plausible that NaHCO3 may be ergogenic by causing beneficial shifts in the strong ion difference (SID), though the time course of this blood acid base balance variable is yet to be investigated. Twelve highly trained, adolescent swimmers (age: 15.9 ± 1.0 years, body mass: 65.3 ± 9.6 kg) consumed their typical pre-competition nutrition 1–3 hours before ingesting 0.3 g∙kg BM-1 NaHCO3 in gelatine capsules. Capillary blood samples were then taken during seated rest on nine occasions (0, 60, 75, 90, 105, 120, 135, 150, 165 min post-ingestion) to identify the time course changes in HCO3–, pH, and the SID. No significant differences were found in the time to peak of each blood measure (HCO3–: 130 ± 35 min, pH: 120 ± 38 min, SID: 98 ± 37 min; p = 0.08); however, a large effect size was calculated between time to peak HCO3– and the SID (g = 0.88). Considering that a difference between time to peak blood HCO3– and the SID was identified in adolescents, future research should compare the ergogenic effects of these two individualized NaHCO3 ingestion strategies compared to a traditional, standardized approach.
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Affiliation(s)
- Josh W. Newbury
- Human Performance and Health Research Group, Centre for Life and Sport Sciences (CLaSS), Department of Sport and Exercise, Birmingham City University, Birmingham, United Kingdom
| | - Matthew Cole
- Human Performance and Health Research Group, Centre for Life and Sport Sciences (CLaSS), Department of Sport and Exercise, Birmingham City University, Birmingham, United Kingdom
| | - Adam L. Kelly
- Human Performance and Health Research Group, Centre for Life and Sport Sciences (CLaSS), Department of Sport and Exercise, Birmingham City University, Birmingham, United Kingdom
| | - Richard J. Chessor
- Sports Science and Sports Medicine Team, British Swimming, Loughborough, Leicestershire, United Kingdom
| | - S. Andy Sparks
- Sports Nutrition and Performance Research Group, Department of Sport and Physical Activity, Edge Hill University, Ormskirk, United Kingdom
- * E-mail:
| | - Lars R. McNaughton
- Sports Nutrition and Performance Research Group, Department of Sport and Physical Activity, Edge Hill University, Ormskirk, United Kingdom
| | - Lewis A. Gough
- Human Performance and Health Research Group, Centre for Life and Sport Sciences (CLaSS), Department of Sport and Exercise, Birmingham City University, Birmingham, United Kingdom
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Hostrup M, Cairns SP, Bangsbo J. Muscle Ionic Shifts During Exercise: Implications for Fatigue and Exercise Performance. Compr Physiol 2021; 11:1895-1959. [PMID: 34190344 DOI: 10.1002/cphy.c190024] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Exercise causes major shifts in multiple ions (e.g., K+ , Na+ , H+ , lactate- , Ca2+ , and Cl- ) during muscle activity that contributes to development of muscle fatigue. Sarcolemmal processes can be impaired by the trans-sarcolemmal rundown of ion gradients for K+ , Na+ , and Ca2+ during fatiguing exercise, while changes in gradients for Cl- and Cl- conductance may exert either protective or detrimental effects on fatigue. Myocellular H+ accumulation may also contribute to fatigue development by lowering glycolytic rate and has been shown to act synergistically with inorganic phosphate (Pi) to compromise cross-bridge function. In addition, sarcoplasmic reticulum Ca2+ release function is severely affected by fatiguing exercise. Skeletal muscle has a multitude of ion transport systems that counter exercise-related ionic shifts of which the Na+ /K+ -ATPase is of major importance. Metabolic perturbations occurring during exercise can exacerbate trans-sarcolemmal ionic shifts, in particular for K+ and Cl- , respectively via metabolic regulation of the ATP-sensitive K+ channel (KATP ) and the chloride channel isoform 1 (ClC-1). Ion transport systems are highly adaptable to exercise training resulting in an enhanced ability to counter ionic disturbances to delay fatigue and improve exercise performance. In this article, we discuss (i) the ionic shifts occurring during exercise, (ii) the role of ion transport systems in skeletal muscle for ionic regulation, (iii) how ionic disturbances affect sarcolemmal processes and muscle fatigue, (iv) how metabolic perturbations exacerbate ionic shifts during exercise, and (v) how pharmacological manipulation and exercise training regulate ion transport systems to influence exercise performance in humans. © 2021 American Physiological Society. Compr Physiol 11:1895-1959, 2021.
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Affiliation(s)
- Morten Hostrup
- Section of Integrative Physiology, Department of Nutrition, Exercise and Sports, University of Copenhagen, Copenhagen, Denmark
| | - Simeon Peter Cairns
- SPRINZ, School of Sport and Recreation, Auckland University of Technology, Auckland, New Zealand.,Health and Rehabilitation Research Institute, Auckland University of Technology, Auckland, New Zealand
| | - Jens Bangsbo
- Section of Integrative Physiology, Department of Nutrition, Exercise and Sports, University of Copenhagen, Copenhagen, Denmark
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Senefeld JW, Keenan KG, Ryan KS, D'Astice SE, Negro F, Hunter SK. Greater fatigability and motor unit discharge variability in human type 2 diabetes. Physiol Rep 2021; 8:e14503. [PMID: 32633071 PMCID: PMC7379048 DOI: 10.14814/phy2.14503] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
This study determined the discharge characteristics of motor units from two lower limb muscles before and after fatiguing exercise in people with type 2 diabetes (T2D) with no symptoms of polyneuropathy and activity‐matched controls. Seventeen people with T2D (65.0 ± 5.6 years; 8 women) and 17 controls (63.6 ± 4.5 years; 8 women) performed: (a) intermittent, isometric contractions at 50% maximal voluntary isometric contraction (MVIC) sustained to failure with the ankle dorsiflexors, and (b) a dynamic fatiguing task (30% MVIC load) for 6 min with the knee extensors. Before and after the fatiguing tasks, motor unit characteristics (including coefficient of variation (CV) of interspike intervals (ISI)) were quantified from high‐density electromyography and muscle contractile properties were assessed via electrical stimulation. Fatigability was ~50% greater for people with T2D than controls for the dorsiflexors (time‐to‐failure: 7.3 ± 4.1 vs. 14.3 ± 9.1 min, p = .010) and knee extensors (power reduction: 56.7 ± 11.9 vs. 31.5 ± 25.5%, p < .001). The CV of ISI was greater for the T2D than control group for the tibialis anterior (23.1 ± 11.0 vs. 21.3 ± 10.7%, p < .001) and vastus lateralis (27.8 ± 20.2 vs. 24.5 ± 16.1%, p = .011), but these differences did not change after the fatiguing exercises. People with T2D had greater reductions in the electrically evoked twitch amplitude of the dorsiflexors (8.5 ± 5.1 vs. 4.0 ± 3.4%·min‐1, p = .013) and knee extensors (49.1 ± 10.0 vs. 31.8 ± 15.9%, p = .004) than controls. Although motor unit activity was more variable in people with T2D than controls, the greater fatigability of the T2D group for lower limb muscles was due to mechanisms involving disruption of contractile function of the exercising muscles rather than motor unit behavior.
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Affiliation(s)
- Jonathon W Senefeld
- Exercise Science Program, Marquette University, Milwaukee, WI, USA.,Department of Physical Therapy, Marquette University, Milwaukee, WI, USA.,Department of Anesthesiology and Perioperative Medicine, Mayo Clinic, Rochester, MN, USA
| | - Kevin G Keenan
- Department of Kinesiology, University of Wisconsin, Milwaukee, WI, USA.,Center for Aging and Translational Research, University of Wisconsin, Milwaukee, WI, USA
| | - Kevin S Ryan
- Exercise Science Program, Marquette University, Milwaukee, WI, USA.,Department of Physical Therapy, Marquette University, Milwaukee, WI, USA
| | - Sarah E D'Astice
- Exercise Science Program, Marquette University, Milwaukee, WI, USA.,Department of Physical Therapy, Marquette University, Milwaukee, WI, USA
| | - Francesco Negro
- Department of Clinical and Experimental Sciences, University of Brescia, Brescia, Italy
| | - Sandra K Hunter
- Exercise Science Program, Marquette University, Milwaukee, WI, USA.,Department of Physical Therapy, Marquette University, Milwaukee, WI, USA
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31
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Urwin CS, Snow RJ, Orellana L, Condo D, Wadley GD, Carr AJ. Does varying the ingestion period of sodium citrate influence blood alkalosis and gastrointestinal symptoms? PLoS One 2021; 16:e0251808. [PMID: 33999939 PMCID: PMC8128256 DOI: 10.1371/journal.pone.0251808] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2021] [Accepted: 05/03/2021] [Indexed: 11/28/2022] Open
Abstract
OBJECTIVES To compare blood alkalosis, gastrointestinal symptoms and indicators of strong ion difference after ingestion of 500 mg.kg-1 BM sodium citrate over four different periods. METHODS Sixteen healthy and active participants ingested 500 mg.kg-1 BM sodium citrate in gelatine capsules over a 15, 30, 45 or 60 min period using a randomized cross-over experimental design. Gastrointestinal symptoms questionnaires and venous blood samples were collected before ingestion, immediately post-ingestion, and every 30 min for 480 min post-ingestion. Blood samples were analysed for blood pH, [HCO3-], [Na+], [Cl-] and plasma [citrate]. Linear mixed models were used to estimate the effect of the ingestion protocols. RESULTS For all treatments, blood [HCO3-] was significantly elevated above baseline for the entire 480 min post-ingestion period, and peak occurred 180 min post-ingestion. Blood [HCO3-] and pH were significantly elevated above baseline and not significantly below the peak between 150-270 min post-ingestion. Furthermore, blood pH and [HCO3-] were significantly lower for the 60 min ingestion period when compared to the other treatments. Gastrointestinal symptoms were minor for all treatments; the mean total session symptoms ratings (all times summed together) were between 9.8 and 11.6 from a maximum possible rating of 720. CONCLUSION Based on the findings of this investigation, sodium citrate should be ingested over a period of less than 60 min (15, 30 or 45 min), and completed 150-270 min before exercise.
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Affiliation(s)
- Charles S. Urwin
- Centre for Sport Research, School of Exercise and Nutrition Sciences, Faculty of Health, Deakin University, Geelong, Victoria, Australia
| | - Rodney J. Snow
- Institute for Physical Activity and Nutrition, School of Exercise and Nutrition Sciences, Faculty of Health, Deakin University, Geelong, Victoria, Australia
| | - Liliana Orellana
- Biostatistics Unit, Faculty of Health, Deakin University, Geelong, Victoria, Australia
| | - Dominique Condo
- Centre for Sport Research, School of Exercise and Nutrition Sciences, Faculty of Health, Deakin University, Geelong, Victoria, Australia
- Institute for Physical Activity and Nutrition, School of Exercise and Nutrition Sciences, Faculty of Health, Deakin University, Geelong, Victoria, Australia
| | - Glenn D. Wadley
- Institute for Physical Activity and Nutrition, School of Exercise and Nutrition Sciences, Faculty of Health, Deakin University, Geelong, Victoria, Australia
| | - Amelia J. Carr
- Centre for Sport Research, School of Exercise and Nutrition Sciences, Faculty of Health, Deakin University, Geelong, Victoria, Australia
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Muscle Glycogen Metabolism and High-Intensity Exercise Performance: A Narrative Review. Sports Med 2021; 51:1855-1874. [PMID: 33900579 DOI: 10.1007/s40279-021-01475-0] [Citation(s) in RCA: 50] [Impact Index Per Article: 16.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/08/2021] [Indexed: 02/06/2023]
Abstract
Muscle glycogen is the main substrate during high-intensity exercise and large reductions can occur after relatively short durations. Moreover, muscle glycogen is stored heterogeneously and similarly displays a heterogeneous and fiber-type specific depletion pattern with utilization in both fast- and slow-twitch fibers during high-intensity exercise, with a higher degradation rate in the former. Thus, depletion of individual fast- and slow-twitch fibers has been demonstrated despite muscle glycogen at the whole-muscle level only being moderately lowered. In addition, muscle glycogen is stored in specific subcellular compartments, which have been demonstrated to be important for muscle function and should be considered as well as global muscle glycogen availability. In the present review, we discuss the importance of glycogen metabolism for single and intermittent bouts of high-intensity exercise and outline possible underlying mechanisms for a relationship between muscle glycogen and fatigue during these types of exercise. Traditionally this relationship has been attributed to a decreased ATP resynthesis rate due to inadequate substrate availability at the whole-muscle level, but emerging evidence points to a direct coupling between muscle glycogen and steps in the excitation-contraction coupling including altered muscle excitability and calcium kinetics.
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33
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Effect of Warm-Up and Sodium Bicarbonate Ingestion on 4-km Cycling Time-Trial Performance. Int J Sports Physiol Perform 2021; 16:1573-1579. [PMID: 33831843 DOI: 10.1123/ijspp.2020-0743] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2020] [Revised: 11/09/2020] [Accepted: 11/24/2020] [Indexed: 11/18/2022]
Abstract
PURPOSE To examine whether an ecologically valid, intermittent, sprint-based warm-up strategy impacted the ergogenic capacity of individualized sodium bicarbonate (NaHCO3) ingestion on 4-km cycling time-trial (TT) performance. METHODS A total of 8 male cyclists attended 6 laboratory visits for familiarization, determination of time to peak blood bicarbonate, and 4 × 4-km cycling TTs. Experimental beverages were administered doubleblind. Treatments were conducted in a block-randomized, crossover order: intermittent warm-up + NaHCO3 (IWSB), intermittent warm-up + placebo, control warm-up + NaHCO3 (CWSB), and control warm-up + placebo (CWP). The intermittent warm-up comprised exercise corresponding to lactate threshold (5 min at 50%, 2 min at 60%, 2 min at 80%, 1 min at 100%, and 2 min at 50%) and 3 × 10-second maximal sprints. The control warm-up comprised 16.5 minutes cycling at 150 W. Participants ingested 0.3 g·kg body mass-1 NaHCO3 or 0.03 g·kg body mass-1 sodium chloride (placebo) in 5 mL·kg body mass-1 fluid (3:2, water and sugar-free orange squash). Paired t tests were conducted for TT performance. Hematological data (blood bicarbonate and blood lactate) and gastrointestinal discomfort were analyzed using repeated-measures analysis of variance. RESULTS Performance was faster for CWSB versus IWSB (5.0 [6.1] s; P = .052) and CWP (5.8 [6.0] s; P = .03). Pre-TT bicarbonate concentration was elevated for CWSB versus IWSB (+9.3 mmol·L-1; P < .001) and CWP (+7.1 mmol·L-1; P < .001). Post-TT blood lactate concentration was elevated for CWSB versus CWP (+2.52 mmol·L-1; P = .022). Belching was exacerbated pre-warm-up for IWSB versus intermittent warm-up +placebo (P = .046) and CWP (P = .027). CONCLUSION An intermittent, sprint-based warm-up mitigated the ergogenic benefits of NaHCO3 ingestion on 4-km cycling TT performance.
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Gurton W, Macrae H, Gough L, King DG. Effects of post-exercise sodium bicarbonate ingestion on acid-base balance recovery and time-to-exhaustion running performance: a randomised crossover trial in recreational athletes. Appl Physiol Nutr Metab 2021; 46:1111-1118. [PMID: 33730517 DOI: 10.1139/apnm-2020-1120] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
This study investigated the effect of post-exercise sodium bicarbonate (NaHCO3) ingestion on acid-base balance recovery and time-to-exhaustion (TTE) running performance. Eleven male runners (stature, 1.80 ± 0.05 m; body mass, 74.4 ± 6.5 kg; maximal oxygen consumption, 51.7 ± 5.4 mL·kg-1·min-1) participated in this randomised, single-blind, counterbalanced and crossover design study. Maximal running velocity (v-V̇O2max) was identified from a graded exercise test. During experimental trials, participants repeated 100% v-V̇O2max TTE protocols (TTE1, TTE2) separated by 40 min following the ingestion of either 0.3 g·kg-1 body mass NaHCO3 (SB) or 0.03 g·kg-1 body mass sodium chloride (PLA) at the start of TTE1 recovery. Acid-base balance (blood pH and bicarbonate, HCO3-) data were studied at baseline, post-TTE1, after 35 min recovery and post-TTE2. Blood pH and HCO3- concentration were unchanged at 35 min recovery (p > 0.05), but HCO3- concentration was elevated post-TTE2 for SB vs. PLA (+2.6 mmol·L-1; p = 0.005; g = 0.99). No significant differences were observed for TTE2 performance (p > 0.05), although a moderate effect size was present for SB vs. PLA (+14.3 s; g = 0.56). Post-exercise NaHCO3 ingestion is not an effective strategy for accelerating the restoration of acid-base balance or improving subsequent TTE performance when limited recovery is available. Novelty: Post-exercise sodium bicarbonate ingestion did not accelerate the restoration of blood pH or bicarbonate after 35 min. Performance enhancing effects of sodium bicarbonate ingestion may display a high degree of inter-individual variation. Small-to-moderate changes in performance were likely due to greater up-regulation of glycolytic activation during exercise.
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Affiliation(s)
- William Gurton
- Surrey Human Performance Institute, University of Surrey, Guildford GU2 7XH, United Kingdom
| | - Heather Macrae
- Surrey Human Performance Institute, University of Surrey, Guildford GU2 7XH, United Kingdom
| | - Lewis Gough
- Research Centre for Life and Sport Sciences (CLaSS), School of Health Sciences, Birmingham City University, Birmingham B15 3TN, United Kingdom
| | - David G King
- Surrey Human Performance Institute, University of Surrey, Guildford GU2 7XH, United Kingdom
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Factors Influencing Blood Alkalosis and Other Physiological Responses, Gastrointestinal Symptoms, and Exercise Performance Following Sodium Citrate Supplementation: A Review. Int J Sport Nutr Exerc Metab 2021; 31:168-186. [PMID: 33440332 DOI: 10.1123/ijsnem.2020-0192] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2020] [Revised: 09/06/2020] [Accepted: 10/10/2020] [Indexed: 11/18/2022]
Abstract
This review aimed to identify factors associated with (a) physiological responses, (b) gastrointestinal (GI) symptoms, and (c) exercise performance following sodium citrate supplementation. A literature search identified 33 articles. Observations of physiological responses and GI symptoms were categorized by dose (< 500, 500, and > 500 mg/kg body mass [BM]) and by timing of postingestion measurements (in minutes). Exercise performance following sodium citrate supplementation was compared with placebo using statistical significance, percentage change, and effect size. Performance observations were categorized by exercise duration (very short < 60 s, short ≥ 60 and ≤ 420 s, and longer > 420 s) and intensity (very high > 100% VO2max and high 90-100% VO2max). Ingestion of 500 mg/kg BM sodium citrate induced blood alkalosis more frequently than < 500 mg/kg BM, and with similar frequency to >500 mg/kg BM. The GI symptoms were minimized when a 500 mg/kg BM dose was ingested in capsules rather than in solution. Significant improvements in performance following sodium citrate supplementation were reported in all observations of short-duration and very high-intensity exercise with a 500 mg/kg BM dose. However, the efficacy of supplementation for short-duration, high-intensity exercise is less clear, given that only 25% of observations reported significant improvements in performance following sodium citrate supplementation. Based on the current literature, the authors recommend ingestion of 500 mg/kg BM sodium citrate in capsules to induce alkalosis and minimize GI symptoms. Supplementation was of most benefit to performance of short-duration exercise of very high intensity; further investigation is required to determine the importance of ingestion duration and timing.
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Barreto G, Grecco B, Merola P, Reis CEG, Gualano B, Saunders B. Novel insights on caffeine supplementation, CYP1A2 genotype, physiological responses and exercise performance. Eur J Appl Physiol 2021; 121:749-769. [PMID: 33403509 DOI: 10.1007/s00421-020-04571-7] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2020] [Accepted: 11/23/2020] [Indexed: 01/13/2023]
Abstract
Caffeine is a popular ergogenic aid due to its primary physiological effects that occur through antagonism of adenosine receptors in the central nervous system. This leads to a cascade of physiological reactions which increases focus and volition, and reduces perception of effort and pain, contributing to improved exercise performance. Substantial variability in the physiological and performance response to acute caffeine consumption is apparent, and a growing number of studies are implicating a single-nucleotide polymorphism in the CYP1A2 gene, responsible for caffeine metabolism, as a key factor that influences the acute responses to caffeine ingestion. However, existing literature regarding the influence of this polymorphism on the ergogenic effects of caffeine is controversial. Fast caffeine metabolisers (AA homozygotes) appear most likely to benefit from caffeine supplementation, although over half of studies showed no differences in the responses to caffeine between CYP1A2 genotypes, while others even showed either a possible advantage or disadvantage for C-allele carriers. Contrasting data are limited by weak study designs and small samples sizes, which did not allow separation of C-allele carriers into their sub-groups (AC and CC), and insufficient mechanistic evidence to elucidate findings. Mixed results prevent practical recommendations based upon genotype while genetic testing for CYP1A2 is also currently unwarranted. More mechanistic and applied research is required to elucidate how the CYP1A2 polymorphism might alter caffeine's ergogenic effect and the magnitude thereof, and whether CYP1A2 genotyping prior to caffeine supplementation is necessary.
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Affiliation(s)
- Gabriel Barreto
- Applied Physiology and Nutrition Research Group, School of Physical Education and Sport, Rheumatology Division, Faculdade de Medicina FMUSP, Universidade de Sao Paulo (Sao Paulo, SP, BR), University of São Paulo, Av. Dr. Arnaldo, 455 - Cerqueira César, São Paulo, SP, 01246903, Brazil
| | - Beatriz Grecco
- Applied Physiology and Nutrition Research Group, School of Physical Education and Sport, Rheumatology Division, Faculdade de Medicina FMUSP, Universidade de Sao Paulo (Sao Paulo, SP, BR), University of São Paulo, Av. Dr. Arnaldo, 455 - Cerqueira César, São Paulo, SP, 01246903, Brazil
| | - Pietro Merola
- Applied Physiology and Nutrition Research Group, School of Physical Education and Sport, Rheumatology Division, Faculdade de Medicina FMUSP, Universidade de Sao Paulo (Sao Paulo, SP, BR), University of São Paulo, Av. Dr. Arnaldo, 455 - Cerqueira César, São Paulo, SP, 01246903, Brazil
| | | | - Bruno Gualano
- Applied Physiology and Nutrition Research Group, School of Physical Education and Sport, Rheumatology Division, Faculdade de Medicina FMUSP, Universidade de Sao Paulo (Sao Paulo, SP, BR), University of São Paulo, Av. Dr. Arnaldo, 455 - Cerqueira César, São Paulo, SP, 01246903, Brazil.,Food Research Center, University of São Paulo, São Paulo, Brazil
| | - Bryan Saunders
- Applied Physiology and Nutrition Research Group, School of Physical Education and Sport, Rheumatology Division, Faculdade de Medicina FMUSP, Universidade de Sao Paulo (Sao Paulo, SP, BR), University of São Paulo, Av. Dr. Arnaldo, 455 - Cerqueira César, São Paulo, SP, 01246903, Brazil. .,Institute of Orthopaedics and Traumatology, Faculty of Medicine FMUSP, University of São Paulo, São Paulo, Brazil.
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Duchateau J, Stragier S, Baudry S, Carpentier A. Strength Training: In Search of Optimal Strategies to Maximize Neuromuscular Performance. Exerc Sport Sci Rev 2021; 49:2-14. [PMID: 33044332 DOI: 10.1249/jes.0000000000000234] [Citation(s) in RCA: 28] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Training with low-load exercise performed under blood flow restriction can augment muscle hypertrophy and maximal strength to a similar extent as the classical high-load strength training method. However, the blood flow restriction method elicits only minor neural adaptations. In an attempt to maximize training-related gains, we propose using other protocols that combine high voluntary activation, mechanical tension, and metabolic stress.
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Affiliation(s)
| | | | | | - Alain Carpentier
- Laboratory for Biometry and Exercise Nutrition, Université Libre de Bruxelles, Brussels, Belgium
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38
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Senefeld JW, Harmer AR, Hunter SK. Greater Lower Limb Fatigability in People with Prediabetes than Controls. Med Sci Sports Exerc 2020; 52:1176-1186. [PMID: 31815831 DOI: 10.1249/mss.0000000000002238] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
INTRODUCTION The study purpose was to compare perceived fatigability and performance fatigability after high-velocity contractions with knee extensor muscles between people with prediabetes, people with type 2 diabetes (T2D), and controls without diabetes matched for age, body mass index, and physical activity. METHODS Twenty people with prediabetes (11 men, 9 women: 63.1 ± 6.0 yr, 26.9 ± 4.2 kg·m, 8030 ± 3110 steps per day), 39 with T2D (23 men, 16 women: 61.2 ± 8.5 yr, 29.4 ± 6.4 kg·m, 8440 ± 4220 steps per day), and 27 controls (13 men, 14 women: 58.1 ± 9.4 yr, 27.3 ± 4.3 kg·m, 8400 ± 3000 steps per day) completed the Fatigue Impact Scale as a measure of perceived fatigability and a fatigue protocol including 120 maximal-effort, high-velocity concentric contractions (MVCC; 1 contraction/3 s) with the knee extensors using a submaximal load (30% maximum) to quantify performance fatigability. Electrical stimulation was used to assess voluntary activation and contractile function of the knee extensor muscles before and after the fatigue protocol. RESULTS Fatigue Impact Scale scores were not different between people with prediabetes, people with T2D, and controls (12.5 ± 15.1, 18.3 ± 22.7, and 12.6 ± 18.6, respectively; P = 0.517). However, people with prediabetes had greater reductions in MVCC power during the fatigue protocol than did controls (31.8% ± 22.6% vs 22.1% ± 21.1%, P < 0.001), and both groups had lesser reductions than the T2D group (44.8% ± 21.9%, P < 0.001). Similarly, the prediabetes group had larger reductions in electrically evoked twitch amplitude than the control group (32.5% ± 24.9% vs 21.3% ± 33.0%, P < 0.001), but lesser reductions than those with T2D (44.0% ± 23.4%, P < 0.001). For all three groups, a greater decline in MVCC power was associated with larger reductions of twitch amplitude (r = 0.350, P < 0.001). CONCLUSION People with prediabetes have greater performance fatigability of the knee extensors due to contractile mechanisms compared with controls, although less performance fatigability than that of people with T2D.
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Affiliation(s)
- Jonathon W Senefeld
- Clinical and Translational Rehabilitation Health Sciences Program, Department of Physical Therapy, Marquette University, Milwaukee, WI
| | - Alison R Harmer
- Musculoskeletal Health Research Group, Faculty of Health Sciences, The University of Sydney, Lidcombe, NSW, AUSTRALIA
| | - Sandra K Hunter
- Clinical and Translational Rehabilitation Health Sciences Program, Department of Physical Therapy, Marquette University, Milwaukee, WI
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Gurton WH, Gough LA, Sparks SA, Faghy MA, Reed KE. Sodium Bicarbonate Ingestion Improves Time-to-Exhaustion Cycling Performance and Alters Estimated Energy System Contribution: A Dose-Response Investigation. Front Nutr 2020; 7:154. [PMID: 33015125 PMCID: PMC7506131 DOI: 10.3389/fnut.2020.00154] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2020] [Accepted: 07/29/2020] [Indexed: 11/23/2022] Open
Abstract
This study investigated the effects of two sodium bicarbonate (NaHCO3) doses on estimated energy system contribution and performance during an intermittent high-intensity cycling test (HICT), and time-to-exhaustion (TTE) exercise. Twelve healthy males (stature: 1.75 ± 0.08 m; body mass: 67.5 ± 6.3 kg; age: 21.0 ± 1.4 years; maximal oxygen consumption: 45.1 ± 7.0 ml.kg.min−1) attended four separate laboratory visits. Maximal aerobic power (MAP) was identified from an incremental exercise test. During the three experimental visits, participants ingested either 0.2 g.kg−1 BM NaHCO3 (SBC2), 0.3 g.kg−1 BM NaHCO3 (SBC3), or 0.07 g.kg−1 BM sodium chloride (placebo; PLA) at 60 min pre-exercise. The HICT involved 3 × 60 s cycling bouts (90, 95, 100% MAP) interspersed with 90 s recovery, followed by TTE cycling at 105% MAP. Blood lactate was measured after each cycling bout to calculate estimates for glycolytic contribution to exercise. Gastrointestinal (GI) upset was quantified at baseline, 30 and 60 min post-ingestion, and 5 min post-exercise. Cycling TTE increased for SBC2 (+20.2 s; p = 0.045) and SBC3 (+31.9 s; p = 0.004) compared to PLA. Glycolytic contribution increased, albeit non-significantly, during the TTE protocol for SBC2 (+7.77 kJ; p = 0.10) and SBC3 (+7.95 kJ; p = 0.07) compared to PLA. GI upset was exacerbated post-exercise after SBC3 for nausea compared to SBC2 and PLA (p < 0.05), whilst SBC2 was not significantly different to PLA for any symptom (p > 0.05). Both NaHCO3 doses enhanced cycling performance and glycolytic contribution, however, higher doses may maximize ergogenic benefits.
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Affiliation(s)
- William H Gurton
- School of Sport, Rehabilitation and Exercise Science, University of Essex, Colchester, United Kingdom
| | - Lewis A Gough
- Research Centre for Life and Sport Sciences (CLaSS) School of Health Sciences, Birmingham City University, Birmingham, United Kingdom
| | - S Andy Sparks
- Sports Nutrition and Performance Group, Department of Sport and Physical Activity, Edge Hill University, Ormskirk, United Kingdom
| | - Mark A Faghy
- Human Sciences Research Centre, University of Derby, Derby, United Kingdom
| | - Katharine E Reed
- School of Sport, Rehabilitation and Exercise Science, University of Essex, Colchester, United Kingdom
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40
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Senefeld JW, Singh-Peters LA, Kenno KA, Hunter SK, Jakobi JM. Greater fatigue resistance of dorsiflexor muscles in people with prediabetes than type 2 diabetes. J Electromyogr Kinesiol 2020; 54:102458. [PMID: 32896804 DOI: 10.1016/j.jelekin.2020.102458] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2020] [Revised: 08/05/2020] [Accepted: 08/19/2020] [Indexed: 11/16/2022] Open
Abstract
Although exercise can prevent progression to T2D among people with prediabetes, little is known about fatigue during exercise in people with prediabetes compared to T2D. The purpose of the study was to compare the magnitude and mechanisms of fatigability of the ankle dorsiflexor muscles between people with prediabetes and T2D. Ten people with prediabetes (6 females, 51.7 ± 6.9 years) and fourteen with T2D (6 females, 52.6 ± 6.2 years) who were matched for age, body mass index and physical activity performed an intermittent (6 s contraction: 4 s relaxation) fatiguing task at 75% maximal voluntary contraction (MVC) with the dorsiflexors. Electrical stimulation was used to assess contractile properties of the dorsiflexor muscles before and after the fatiguing task. People with prediabetes had a longer time-to-task failure, i.e. greater fatigue resistance (7.9 ± 5.1 vs. 4.9 ± 2.5 min, P = 0.04), and slower rate of decline of the (potentiated) twitch amplitude (6.5 ± 3.1 vs. 16.5 ± 11.7%·min-1, P = 0.03) than people with T2D. Shorter time-to-task failure (i.e. greater fatigability) was associated with greater baseline MVC torque (r2 = 0.21, P = 0.02) and faster rate of decline of twitch amplitude (r2 = 0.39, P = 0.04). The ankle dorsiflexor muscles of males and females with prediabetes were more fatigue resistant than people with T2D, and fatigability was associated with contractile mechanisms.
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Affiliation(s)
- Jonathon W Senefeld
- Department of Anesthesiology and Perioperative Medicine, Mayo Clinic, Rochester, MN, USA; Department of Physical Therapy, Marquette University, Milwaukee, WI, USA
| | | | - Kenji A Kenno
- Department of Kinesiology, University of Windsor, Windsor, ON, Canada
| | - Sandra K Hunter
- Department of Physical Therapy, Marquette University, Milwaukee, WI, USA
| | - Jennifer M Jakobi
- School of Health and Exercise Sciences, The University of British Columbia-Okanagan, Kelowna, BC, Canada.
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Enteric-coated sodium bicarbonate supplementation improves high-intensity cycling performance in trained cyclists. Eur J Appl Physiol 2020; 120:1563-1573. [PMID: 32388584 PMCID: PMC7295736 DOI: 10.1007/s00421-020-04387-5] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2020] [Accepted: 05/02/2020] [Indexed: 12/01/2022]
Abstract
Purpose Enteric-coated sodium bicarbonate (NaHCO3) can attenuate gastrointestinal (GI) symptoms following acute bicarbonate loading, although the subsequent effects on exercise performance have not been investigated. The purpose of this study was to examine the effects of enteric-coated NaHCO3 supplementation on high-intensity exercise performance and GI symptoms. Methods Eleven trained male cyclists completed three 4 km time trials after consuming; a placebo or 0.3 g∙kg–1 body mass NaHCO3 in enteric-coated or gelatin capsules. Exercise trials were timed with individual peak blood bicarbonate ion concentration ([HCO3–]). Blood acid–base balance was measured pre-ingestion, pre-exercise, and post-exercise, whereas GI symptoms were recorded pre-ingestion and immediately pre-exercise. Results Pre-exercise blood [HCO3−] and potential hydrogen (pH) were greater for both NaHCO3 conditions (P < 0.0005) when compared to placebo. Performance time was faster with enteric-coated (− 8.5 ± 9.6 s, P = 0.044) and gelatin (− 9.6 ± 7.2 s, P = 0.004) NaHCO3 compared to placebo, with no significant difference between conditions (mean difference = 1.1 ± 5.3 s, P = 1.000). Physiological responses were similar between conditions, although blood lactate ion concentration was higher with gelatin NaHCO3 (2.4 ± 1.7 mmol∙L–1, P = 0.003) compared with placebo. Furthermore, fewer participants experienced GI symptoms with enteric-coated (n = 3) compared to gelatin (n = 7) NaHCO3. Discussion Acute enteric-coated NaHCO3 consumption mitigates GI symptoms at the onset of exercise and improves subsequent 4 km cycling TT performance. Athletes who experience GI side-effects after acute bicarbonate loading may, therefore, benefit from enteric-coated NaHCO3 supplementation prior to exercise performance.
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Limmer M, de Marées M, Platen P. Effects of daily ingestion of sodium bicarbonate on acid-base status and anaerobic performance during an altitude sojourn at high altitude: a randomized controlled trial. J Int Soc Sports Nutr 2020; 17:22. [PMID: 32307012 PMCID: PMC7168960 DOI: 10.1186/s12970-020-00351-y] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2019] [Accepted: 04/03/2020] [Indexed: 01/18/2023] Open
Abstract
Background The present study investigated the effects of chronic sodium bicarbonate (NaHCO3) ingestion on a single bout of high-intensity exercise and on acid-base balance during 7-day high-altitude exposure. Methods Ten recreationally active subjects participated in a pre-test at sea level and a 7-day hiking tour in the Swiss Alps up to 4554 m above sea level. Subjects received either a daily dose of 0.3 g/kg NaHCO3 solution (n = 5) or water as a placebo (n = 5) for 7 days. Anaerobic high-intensity exercise performance was assessed using the portable tethered sprint running (PTSR) test under normoxic and hypoxic conditions (3585 m). PTSR tests assessed overall peak force, mean force, and fatigue index. Blood lactate levels and blood gas parameters were assessed pre- and post-PTSR. Urinary pH and blood gas parameters were further analyzed daily at rest in early morning samples under normoxic and hypoxic conditions. Results There were no significant differences between the bicarbonate and control group in any of the PTSR-related parameters. However, urinary pH (p = 0.003, ηp2 = 0.458), early morning blood bicarbonate concentration (p < 0.001, ηp2 = 0.457) and base excess (p = 0.002, ηp2 = 0.436) were significantly higher in the bicarbonate group compared with the control group under hypoxic conditions. Conclusions These results indicate that oral NaHCO3 ingestion does not ameliorate the hypoxia-induced impairment in anaerobic, high-intensity exercise performance, represented by PTSR-related test parameters, under hypobaric, hypoxic conditions, but the maximal performance measurements may have been negatively affected by other factors, such as poor implementation of PTSR test instructions, pre-acclimatization, the time course of hypoxia-induced renal [HCO3−] compensation, changes in the concentrations of intra- and extracellular ions others than [H+] and [HCO3−], or gastrointestinal disturbances caused by NaHCO3 ingestion. However, chronic NaHCO3 ingestion improves blood bicarbonate concentration and base excess at altitude, which partially represent the blood buffering capacity.
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Affiliation(s)
- Mirjam Limmer
- Department of Sports Medicine and Sports Nutrition, Ruhr-Universität Bochum, Gesundheitscampus Nord 10, 44801, Bochum, Germany. .,Institute of Outdoor Sports and Environmental Science, German Sport University Cologne, Cologne, Germany.
| | - Markus de Marées
- Department of Sports Medicine and Sports Nutrition, Ruhr-Universität Bochum, Gesundheitscampus Nord 10, 44801, Bochum, Germany
| | - Petra Platen
- Department of Sports Medicine and Sports Nutrition, Ruhr-Universität Bochum, Gesundheitscampus Nord 10, 44801, Bochum, Germany
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Effects of an Alkalizing or Acidizing Diet on High-Intensity Exercise Performance under Normoxic and Hypoxic Conditions in Physically Active Adults: A Randomized, Crossover Trial. Nutrients 2020; 12:nu12030688. [PMID: 32143278 PMCID: PMC7146607 DOI: 10.3390/nu12030688] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2020] [Revised: 02/29/2020] [Accepted: 03/02/2020] [Indexed: 12/17/2022] Open
Abstract
Pre-alkalization caused by dietary supplements such as sodium bicarbonate improves anaerobic exercise performance. However, the influence of a base-forming nutrition on anaerobic performance in hypoxia remains unknown. Herein, we investigated the effects of an alkalizing or acidizing diet on high-intensity performance and associated metabolic parameters in normoxia and hypoxia. In a randomized crossover design, 15 participants (24.5 ± 3.9 years old) performed two trials following four days of either an alkalizing (BASE) or an acidizing (ACID) diet in normoxia. Subsequently, participants performed two trials (BASE; ACID) after 12 h of normobaric hypoxic exposure. Anaerobic exercise performance was assessed using the portable tethered sprint running (PTSR) test. PTSR assessed overall peak force, mean force, and fatigue index. Blood lactate levels, blood gas parameters, heart rate, and rate of perceived exertion were assessed post-PTSR. Urinary pH was analyzed daily. There were no differences between BASE and ACID conditions for any of the PTSR-related parameters. However, urinary pH, blood pH, blood bicarbonate concentration, and base excess were significantly higher in BASE compared with ACID (p < 0.001). These findings show a diet-induced increase in blood buffer capacity, represented by blood bicarbonate concentration and base excess. However, diet-induced metabolic changes did not improve PTSR-related anaerobic performance.
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Tzatzakis T, Papanikolaou K, Draganidis D, Tsimeas P, Kritikos S, Poulios A, Laschou VC, Deli CK, Chatzinikolaou A, Batrakoulis A, Basdekis G, Mohr M, Krustrup P, Jamurtas AZ, Fatouros IG. Recovery Kinetics After Speed-Endurance Training in Male Soccer Players. Int J Sports Physiol Perform 2020; 15:395-408. [PMID: 31751937 DOI: 10.1123/ijspp.2018-0984] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2018] [Revised: 06/08/2019] [Accepted: 06/11/2019] [Indexed: 11/18/2022]
Abstract
PURPOSE To determine the recovery kinetics of performance, muscle damage, and neuromuscular fatigue following 2 speed-endurance production training (SEPT) protocols in soccer. METHODS Ten well-trained, male soccer athletes randomly completed 3 trials: work-to-rest ratio (SEPT) 1:5, SEPT/1:8, and a control trial. Training load during SEPT was monitored using global positioning system and heart-rate monitors. Performance (isokinetic strength of knee extensors and flexors, speed, and countermovement jump) and muscle damage (delayed-onset muscle soreness [DOMS] and creatine kinase) were evaluated at baseline and at 0, 24, 48 and 72 h posttraining. Maximal voluntary contraction (fatigue index) of knee extensors and flexors was additionally assessed at 1, 2, and 3 h posttraining. RESULTS Fatigue increased (P < .05) in SEPT/1:5 (∼4-30%) for 3 h and in SEPT/1:8 (∼8-17%) for 2 h. Strength performance declined (P < .05) in both SEPT trials (∼5-20%) for 48 h. Speed decreased (∼4-18%; P < .05) for 72 h in SEPT/1:5 and for 48 h in SEPT/1:8. Countermovement-jump performance decreased (∼7-12%; P < .05) in both SEPT trials for 24 h. DOMS increased (P < .05) in SEPT/1:5 (∼2-fold) for 72 and in SEPT/1:8 (∼1- to 2-fold) for 48 h. Creatine kinase increased (∼1- to 2-fold, P < .05) in both SEPT trials for 72 h. CONCLUSIONS SEPT induces short-term neuromuscular fatigue; provokes a prolonged deterioration of strength (48 h), speed (72 h), and jump performance (24 h); and is associated with a prolonged (72-h) rise of DOMS and creatine kinase. Time for recovery is reduced when longer work-to-rest ratios are applied. Fitness status may affect quality of SEPT and recovery kinetics.
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Supplements and Nutritional Interventions to Augment High-Intensity Interval Training Physiological and Performance Adaptations-A Narrative Review. Nutrients 2020; 12:nu12020390. [PMID: 32024038 PMCID: PMC7071320 DOI: 10.3390/nu12020390] [Citation(s) in RCA: 31] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2019] [Revised: 01/22/2020] [Accepted: 01/29/2020] [Indexed: 12/13/2022] Open
Abstract
High-intensity interval training (HIIT) involves short bursts of intense activity interspersed by periods of low-intensity exercise or rest. HIIT is a viable alternative to traditional continuous moderate-intensity endurance training to enhance maximal oxygen uptake and endurance performance. Combining nutritional strategies with HIIT may result in more favorable outcomes. The purpose of this narrative review is to highlight key dietary interventions that may augment adaptations to HIIT, including creatine monohydrate, caffeine, nitrate, sodium bicarbonate, beta-alanine, protein, and essential amino acids, as well as manipulating carbohydrate availability. Nutrient timing and potential sex differences are also discussed. Overall, sodium bicarbonate and nitrates show promise for enhancing HIIT adaptations and performance. Beta-alanine has the potential to increase training volume and intensity and improve HIIT adaptations. Caffeine and creatine have potential benefits, however, longer-term studies are lacking. Presently, there is a lack of evidence supporting high protein diets to augment HIIT. Low carbohydrate training enhances the upregulation of mitochondrial enzymes, however, there does not seem to be a performance advantage, and a periodized approach may be warranted. Lastly, potential sex differences suggest the need for future research to examine sex-specific nutritional strategies in response to HIIT.
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Olsson K, Cheng AJ, Al‐Ameri M, Wyckelsma VL, Rullman E, Westerblad H, Lanner JT, Gustafsson T, Bruton JD. Impaired sarcoplasmic reticulum Ca2+release is the major cause of fatigue‐induced force loss in intact single fibres from human intercostal muscle. J Physiol 2019; 598:773-787. [DOI: 10.1113/jp279090] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2019] [Accepted: 11/22/2019] [Indexed: 12/15/2022] Open
Affiliation(s)
- Karl Olsson
- Department of Laboratory MedicineSection of Clinical PhysiologyKarolinska Institutet Alfred Nobels Allé 8 141 52 Huddinge Sweden
| | - Arthur J. Cheng
- Department of Physiology and PharmacologyBiomedicum C5Karolinska Institutet Tomtebodavägen 16 Solna 171 65 Sweden
- School of Kinesiology and Health ScienceFaculty of HealthYork University 4700 Keele Street Toronto Canada M3J 1P3
| | - Mamdoh Al‐Ameri
- Department of Molecular Medicine and SurgeryKarolinska InstitutetKarolinska University Hospital Solna 171 76 Stockholm Sweden
| | - Victoria L. Wyckelsma
- Department of Physiology and PharmacologyBiomedicum C5Karolinska Institutet Tomtebodavägen 16 Solna 171 65 Sweden
| | - Eric Rullman
- Department of Laboratory MedicineSection of Clinical PhysiologyKarolinska Institutet Alfred Nobels Allé 8 141 52 Huddinge Sweden
| | - Håkan Westerblad
- Department of Physiology and PharmacologyBiomedicum C5Karolinska Institutet Tomtebodavägen 16 Solna 171 65 Sweden
| | - Johanna T. Lanner
- Department of Physiology and PharmacologyBiomedicum C5Karolinska Institutet Tomtebodavägen 16 Solna 171 65 Sweden
| | - Thomas Gustafsson
- Department of Laboratory MedicineSection of Clinical PhysiologyKarolinska Institutet Alfred Nobels Allé 8 141 52 Huddinge Sweden
| | - Joseph D. Bruton
- Department of Physiology and PharmacologyBiomedicum C5Karolinska Institutet Tomtebodavägen 16 Solna 171 65 Sweden
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Milioni F, de Poli RAB, Saunders B, Gualano B, da Rocha AL, Sanchez Ramos da Silva A, Muller PDTG, Zagatto AM. Effect of β-alanine supplementation during high-intensity interval training on repeated sprint ability performance and neuromuscular fatigue. J Appl Physiol (1985) 2019; 127:1599-1610. [DOI: 10.1152/japplphysiol.00321.2019] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
The study investigated the influence of β-alanine supplementation during a high-intensity interval training (HIIT) program on repeated sprint ability (RSA) performance. This study was randomized, double-blinded, and placebo controlled. Eighteen men performed an incremental running test until exhaustion (TINC) at baseline and followed by 4-wk HIIT (10 × 1-min runs 90% maximal TINCvelocity [1-min recovery]). Then, participants were randomized into two groups and performed a 6-wk HIIT associated with supplementation of 6.4 g/day of β-alanine (Gβ) or dextrose (placebo group; GP). Pre- and post-6-wk HIIT + supplementation, participants performed the following tests: 1) TINC; 2) supramaximal running test; and 3) 2 × 6 × 35-m sprints (RSA). Before and immediately after RSA, neuromuscular function was assessed by vertical jumps, maximal isometric voluntary contractions of knee extension, and neuromuscular electrical stimulations. Muscle biopsies were performed to determine muscle carnosine content, muscle buffering capacity in vitro (βmin vitro), and content of phosphofructokinase (PFK), monocarboxylate transporter 4 (MCT4), and hypoxia-inducible factor-1α (HIF-1α). Both groups showed a significant time effect for maximal oxygen uptake (Gβ: 6.2 ± 3.6% and GP: 6.5 ± 4.2%; P > 0.01); only Gβ showed a time effect for total (−3.0 ± 2.0%; P = 0.001) and best (−3.3 ± 3.0%; P = 0.03) RSA times. A group-by-time interaction was shown after HIIT + Supplementation for muscle carnosine (Gβ: 34.4 ± 2.3 mmol·kg−1·dm−1and GP: 20.7 ± 3.0 mmol·kg−1·dm−1; P = 0.003) and neuromuscular voluntary activation after RSA (Gβ: 87.2 ± 3.3% and GP: 78.9 ± 12.4%; P = 0.02). No time effect or group-by-time interaction was shown for supramaximal running test performance, βm, and content of PFK, MCT4, and HIF-1α. In summary, β-alanine supplementation during HIIT increased muscle carnosine and attenuated neuromuscular fatigue, which may contribute to an enhancement of RSA performance.NEW & NOTEWORTHY β-Alanine supplementation during a high-intensity interval training program increased repeated sprint performance. The improvement of muscle carnosine content induced by β-alanine supplementation may have contributed to an attenuation of central fatigue during repeated sprint. Overall, β-alanine supplementation may be a useful dietary intervention to prevent fatigue.
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Affiliation(s)
- Fabio Milioni
- Post Graduate Program in Human Movement Sciences, Laboratory of Physiology and Human Performance, São Paulo State University, Bauru, São Paulo, Brazil
| | - Rodrigo Araújo Bonetti de Poli
- Post Graduate Program in Human Movement Sciences, Laboratory of Physiology and Human Performance, São Paulo State University, Bauru, São Paulo, Brazil
| | - Bryan Saunders
- Applied Physiology and Nutrition Research Group, Faculdade de Medicina da Universidade de São Paul, Rheumatology Division, School of Physical Education and Sport, University of São Paulo, São Paulo, São Paulo, Brazil
- Faculdade de Medicina da Universidade de São Paulo, Institute of Orthopaedics and Traumatology, University of São Paulo, Brazil
| | - Bruno Gualano
- Applied Physiology and Nutrition Research Group, Faculdade de Medicina da Universidade de São Paul, Rheumatology Division, School of Physical Education and Sport, University of São Paulo, São Paulo, São Paulo, Brazil
| | - Alisson L. da Rocha
- School of Physical Education and Sports of Ribeirão Preto, University of São Paulo, Ribeirão Preto, São Paulo, Brazil
| | | | - Paulo de Tarso Guerrero Muller
- Laboratory of Respiratory Pathophysiology, Mato Grosso do Sul Federal University, Campo Grande, Mato Grosso do Sul, São Paulo, Brazil
| | - Alessandro Moura Zagatto
- Post Graduate Program in Human Movement Sciences, Laboratory of Physiology and Human Performance, São Paulo State University, Bauru, São Paulo, Brazil
- Faculty of Sciences, Department of Physical Education, São Paulo State University, Bauru, São Paulo, Brazil
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Cè E, Longo S, Limonta E, Coratella G, Rampichini S, Esposito F. Peripheral fatigue: new mechanistic insights from recent technologies. Eur J Appl Physiol 2019; 120:17-39. [DOI: 10.1007/s00421-019-04264-w] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2019] [Accepted: 11/12/2019] [Indexed: 12/12/2022]
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49
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Rezaei S, Akbari K, Gahreman DE, Sarshin A, Tabben M, Kaviani M, Sadeghinikoo A, Koozehchian MS, Naderi A. Caffeine and sodium bicarbonate supplementation alone or together improve karate performance. J Int Soc Sports Nutr 2019; 16:44. [PMID: 31623659 PMCID: PMC6798418 DOI: 10.1186/s12970-019-0313-8] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2019] [Accepted: 09/25/2019] [Indexed: 11/28/2022] Open
Abstract
Background The ergogenic properties of acute caffeine (CAF) and sodium bicarbonate (NaHCO3) ingestion on athletic performance have been previously investigated. However, each sport has unique physiological and technical characteristics which warrants optimizing supplementations strategies for maximizing performance. This study examined the effects of CAF and NaHCO3 ingestion on physiological responses and rate of perceived exertion during a Karate-specific aerobic test (KSAT) in competitive karatekas. Methods In a double-blind, crossover, randomized placebo-controlled trial, eight Karatekas underwent five experimental conditions including control (CON), placebo (PLA), CAF, NaHCO3, and CAF + NaHCO3 before completing KSAT. Capsules containing 6 mg/kg BW CAF were consumed 50 min prior to a KSAT whilst 0.3 g/kg BW NaHCO3 was consumed for 3 days leading to and 120, 90, and 60 min prior to a KSAT. Time to exhaustion (TTE), rate of perceived exertion (RPE), and blood lactate (BL) were measured before, immediately after and 3 min following KSAT. Results TTE was significantly greater following CAF, NaHCO3, and CAF + NaHCO3 consumption compared to PLA and CON. However, the differences between CAF, NaHCO3, and CAF + NaHCO3 were not statistically significant (p > 0.05). BL increased significantly from baseline to immediately after and 3 min following KSAT in all conditions (p < 0.01), while RPE at the end of KSAT was not significantly different between conditions (p = 0.11). Conclusions Karate practitioners may benefit from the ergogenic effects of CAF and NaHCO3 when consumed separately or together.
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Affiliation(s)
- Sajjad Rezaei
- Physical Education and Sport Sciences Department, Faculty of Humanities, Tarbiat Modares University, Tehran, Iran
| | - Kazem Akbari
- Department of exercise physiology, Faculty of Physical education and sport sciences, Kharazmi University, Tehran, Iran. .,Raad Sports Club, Tehran, Iran.
| | - Daniel E Gahreman
- College of Health and Human Sciences, Charles Darwin University, Darwin, Australia
| | - Amir Sarshin
- Faculty of Physical education and sport sciences, Department of Exercise Physiology, Karaj Branch, Islamic Azad University, Karaj, Iran
| | - Montassar Tabben
- Aspetar, Qatar Orthopaedic and Sports Medicine Hospital, Doha, Qatar
| | - Mojtaba Kaviani
- School of Nutrition and Dietetics, Acadia University, Wolfville, Nova Scotia, Canada
| | | | - Majid S Koozehchian
- Department of Kinesiology, Jacksonville State University, Jacksonville, AL, 36265, USA
| | - Alireza Naderi
- Sports Physiology Department, Islamic Azad University, Boroujerd Branch, Boroujerd, Iran
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Unger M, Debold EP. Acidosis decreases the Ca 2+ sensitivity of thin filaments by preventing the first actomyosin interaction. Am J Physiol Cell Physiol 2019; 317:C714-C718. [PMID: 31339771 DOI: 10.1152/ajpcell.00196.2019] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Intracellular acidosis is a putative agent of skeletal muscle fatigue, in part, because it depresses the calcium (Ca2+) sensitivity of the myofilaments. However, the molecular mechanism behind this depression in Ca2+ sensitivity is unknown, providing a significant challenge to a complete understanding of the fatigue process. To elucidate this mechanism, we directly determined the effect of acidosis on the ability of a single myosin molecule to bind to a regulated actin filament in a laser trap assay. Decreasing pH from 7.4 to 6.5 significantly (P < 0.05) reduced the frequency of single actomyosin-binding events at submaximal (pCa 8-pCa 6) but not at maximal Ca2+ concentration (pCa 5-pCa 4). To delineate whether this was due to a direct effect on myosin versus an indirect effect on the regulatory proteins troponin (Tn) and tropomyosin (Tm), binding frequency was also quantified in the absence of Tn and Tm. This revealed that acidosis did not significantly alter the frequency of actomyosin binding events in the absence of regulatory proteins (1.4 ± 0.15 vs. 1.4 ± 0.15 events/s for pH 7.4 and 6.5, respectively). Acidosis also did not significantly affect the size of myosin's powerstroke or the duration of binding events in the presence of regulatory proteins, at every [Ca2+]. These data suggest acidosis impedes activation of the thin filament by competitively inhibiting Ca2+ binding to TnC. This slows the rate at which myosin initially attaches to actin; therefore, less cross bridges will be bound and generating force at any given submaximal [Ca2+]. These data provide a molecular explanation for the acidosis-induced decrease in force observed at the submaximal Ca2+ concentrations that might contribute to the loss of force during muscle fatigue.
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Affiliation(s)
- Matthew Unger
- Muscle Biophysics Laboratory, Department of Kinesiology, University of Massachusetts, Amherst, Massachusetts
| | - Edward P Debold
- Muscle Biophysics Laboratory, Department of Kinesiology, University of Massachusetts, Amherst, Massachusetts
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