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Amawi A, AlKasasbeh W, Jaradat M, Almasri A, Alobaidi S, Hammad AA, Bishtawi T, Fataftah B, Turk N, Saoud HA, Jarrar A, Ghazzawi H. Athletes' nutritional demands: a narrative review of nutritional requirements. Front Nutr 2024; 10:1331854. [PMID: 38328685 PMCID: PMC10848936 DOI: 10.3389/fnut.2023.1331854] [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: 11/01/2023] [Accepted: 12/21/2023] [Indexed: 02/09/2024] Open
Abstract
Nutrition serves as the cornerstone of an athlete's life, exerting a profound impact on their performance and overall well-being. To unlock their full potential, athletes must adhere to a well-balanced diet tailored to their specific nutritional needs. This approach not only enables them to achieve optimal performance levels but also facilitates efficient recovery and reduces the risk of injuries. In addition to maintaining a balanced diet, many athletes also embrace the use of nutritional supplements to complement their dietary intake and support their training goals. These supplements cover a wide range of options, addressing nutrient deficiencies, enhancing recovery, promoting muscle synthesis, boosting energy levels, and optimizing performance in their respective sports or activities. The primary objective of this narrative review is to comprehensively explore the diverse nutritional requirements that athletes face to optimize their performance, recovery, and overall well-being. Through a thorough literature search across databases such as PubMed, Google Scholar, and Scopus, we aim to provide evidence-based recommendations and shed light on the optimal daily intakes of carbohydrates, protein, fats, micronutrients, hydration strategies, ergogenic aids, nutritional supplements, and nutrient timing. Furthermore, our aim is to dispel common misconceptions regarding sports nutrition, providing athletes with accurate information and empowering them in their nutritional choices.
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Affiliation(s)
- Adam Amawi
- Department of Exercise Science and Kinesiology, School of Sport Science, The University of Jordan, Amman, Jordan
| | - Walaa AlKasasbeh
- Department of Physical and Health Education, Faculty of Educational Sciences, Al-Ahliyya Amman University, Amman, Jordan
| | - Manar Jaradat
- Department of Nutrition and Food Technology, School of Agriculture, The University of Jordan, Amman, Jordan
| | - Amani Almasri
- Department of Nutrition and Food Technology, School of Agriculture, The University of Jordan, Amman, Jordan
| | - Sondos Alobaidi
- Department of Nutrition and Food Technology, School of Agriculture, The University of Jordan, Amman, Jordan
| | - Aya Abu Hammad
- Department of Nutrition and Food Technology, School of Agriculture, The University of Jordan, Amman, Jordan
| | - Taqwa Bishtawi
- Department of Nutrition and Food Technology, School of Agriculture, The University of Jordan, Amman, Jordan
| | - Batoul Fataftah
- Department of Nutrition and Food Technology, School of Agriculture, The University of Jordan, Amman, Jordan
| | - Nataly Turk
- Department of Family and Community Medicine, Faculty of Medicine, The University of Jordan, Amman, Jordan
| | - Hassan Al Saoud
- Department of Exercise Science and Kinesiology, School of Sport Science, The University of Jordan, Amman, Jordan
| | - Amjad Jarrar
- Department of Nutrition and Health, College of Medicine and Health Sciences, United Arab Emirates University, Al Ain, United Arab Emirates
- Oxford Brookes Center for Nutrition and Health, Faculty of Health and Life Sciences, Oxford Brookes University, Oxford, United Kingdom
| | - Hadeel Ghazzawi
- Department of Nutrition and Food Technology, School of Agriculture, The University of Jordan, Amman, Jordan
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Ojeda ÁH, Barahona-Fuentes G, Galdames Maliqueo S, Guzmán Solis M, Cabrera MMY, Jorquera-Aguilera C. Acute Supplementation with Beta-Alanine Improves Performance in Aerobic-Anaerobic Transition Zones in Endurance Athletes. JOURNAL OF THE AMERICAN NUTRITION ASSOCIATION 2023; 42:187-194. [PMID: 35512767 DOI: 10.1080/07315724.2021.2020183] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
To determine the acute effect of low and high-dose BA trials on maximal aerobic speed (MAS) in endurance athletes. We hypothesized that high doses of BA have a greater effect than low doses, both compared to baseline. Twelve male endurance athletes volunteered for the study (age = 21.8 ± 2.37 years, weight = 69.8 ± 4.36 kg, height = 174 ± 5.45 cm, maximal oxygen uptake = 59.6 ± 3.77 mLO2·kg-1·min-1). The experimental design applied was randomized cross-over, double-blind. Treatment included three 6-minute run tests (6-MRT), the first as a baseline, then randomized 6-MRT with low (30 mg·kg-1) and high (45 mg·kg-1) dose BA trials. The 6-MRTs were separated by 72 hours. The main variable of the study was the distance (m) performed in the 6-MRT. Differences between tests were established through ANOVA and Tukey's multiple comparison tests (p < 0.05). The analysis showed significant differences between baseline and both doses (p < 0.001). No significant differences were observed between low and high-dose BA trials (p > 0.05). Both 30 and 45 mg·kg-1 of BA increased physical performance at maximal aerobic speed in endurance athletes. The acute intake formats described in the present investigation may be helpful for endurance athletes training and competing in aerobic-anaerobic transition zones.
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Affiliation(s)
- Álvaro Huerta Ojeda
- Grupo de Investigación en Salud, Actividad Física y Deporte ISAFYD, Universidad de Las Américas, sede Viña del Mar, Chile
| | - Guillermo Barahona-Fuentes
- Grupo de Investigación en Salud, Actividad Física y Deporte ISAFYD, Universidad de Las Américas, sede Viña del Mar, Chile
| | - Sergio Galdames Maliqueo
- Grupo de Investigación en Salud, Actividad Física y Deporte ISAFYD, Universidad de Las Américas, sede Viña del Mar, Chile
| | - Marcela Guzmán Solis
- Facultad de Educación Física y Deporte, Escuela Naval "Arturo Prat", Valparaíso, Chile
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Weinstein Y, Ovadia Y, Weinstein B, Weinstein A. The Effects of Amorphous Calcium Carbonate (ACC) Supplementation on Resistance Exercise Performance in Women. Nutrients 2023; 15:nu15030538. [PMID: 36771244 PMCID: PMC9919417 DOI: 10.3390/nu15030538] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2022] [Revised: 01/11/2023] [Accepted: 01/17/2023] [Indexed: 01/21/2023] Open
Abstract
The effects of 9 weeks of amorphous calcium carbonate (ACC) supplementation (1000 mg/day) and resistance exercise training (RT) on one repetition maximum (1-RM) values were tested. Thirty-one women (33.1 ± 7.3 y) were randomly assigned into a supplement (ACC, n = 14) or a placebo (PL, n = 17) group. On day 1 and following 9 weeks of intervention, the participants underwent anthropometric measurements and filled out a food frequency questionnaire (FFQ) and sports injuries questionnaires. 1-RM values were measured for the back squat and bench press exercises. All the participants significantly (p = 0.01) improved their mean back squat and bench press 1-RM values (time effect). While no between-group difference was observed in the bench press 1-RM values, the ACC groups' mean post-pre bench press 1-RM differences (Δ1-RM) were significantly higher than in the PL group, expressed in kg (p = 0.049), per body mass (p = 0.042), or per lean body mass (p = 0.035). No significant interaction was observed for time X group effect (p = 0.421). No differences (within- or between-groups) were observed in the anthropometric values or in the questionnaires' results. ACC supplementation revealed an ergogenic effect by augmenting the improvement of maximum amount generated force, which can possibly be attributed to the calcium and/or the carbonate components.
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Affiliation(s)
- Yitzhak Weinstein
- Department of Nutritional Sciences, Tel-Hai Academic College, Kiryat Shmone 1220800, Israel
- Correspondence:
| | - Yarden Ovadia
- Department of Nutritional Sciences, Tel-Hai Academic College, Kiryat Shmone 1220800, Israel
| | - Bar Weinstein
- Department of Statistics and Operations Research, Tel Aviv University, Tel Aviv 6997801, Israel
| | - Ayelet Weinstein
- Department of Nutritional Sciences, Tel-Hai Academic College, Kiryat Shmone 1220800, Israel
- Department of Sports Medicine and Research, Wingate Institute, Netanya 4290200, Israel
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Franco GS, Noronha NY, Oliveira BA, Ferreira FC, Pinto AP, Brandao CF, Papoti M, Nonino CB. Beta-alanine fails to improve on 5000 m running time despite increasing PAT1 expression in long-distance runners. J Sports Med Phys Fitness 2020; 61:1605-1612. [PMID: 33305552 DOI: 10.23736/s0022-4707.20.11946-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
BACKGROUND Beta-alanine has become a dietary supplement widely used by athletes due to its ergogenic effect. However, there is still no consensus on the performance benefit of beta-alanine on exercise lasting longer than ten minutes. The present study aimed to evaluate the effect of beta-alanine supplementation on running performance and the expression of TauT and PAT1. METHODS This double-blind, randomized study enrolled 16 long-distance runners (37±8 years) who were randomly allocated to two groups: placebo (PLA) and beta-alanine (BA) (4.8 g/day 1) for four weeks. Maximal oxygen consumption, anthropometry, body composition, and food intake were determined. Before and after the intervention, the athletes undertook a 5000 m running time trial. Venous blood (TauT and PAT1 expressions) and ear lobe capillary blood (lactate) collected before and after exercise. Between tests, we monitored the training variables. RESULTS The results were analyzed by t-tests and an ANOVA of repeated measures, with Sidak's post hoc (P<0.05). PLA exhibited lower body fat than BA (8.7±2.2 vs. 11.5±2.8%, P=0.04). After supplementation, there was an increase in PAT1 expression in BA when compared to PLA (1.17±0.47 vs. 0.77±0.18, P=0.04). No significant differences were shown for the 5000 m running time in PLA (PRE: 1128±72; POST: 1123±72s) and BA (PRE: 1107±95; POST: 1093±86s). CONCLUSIONS Although beta-alanine supplementation increased PAT1 expression, there was no statistically significant improvement in 5000 m running performance. However, individual responses should be considered as the BA showed a higher delta than the PLA.
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Affiliation(s)
- Gabriel S Franco
- Department of Internal Medicine, Laboratory of Nutrigenomics Studies, Faculty of Medicine, University of São Paulo, Ribeirão Preto, Brazil - .,Departament of Nutrition, University of Franca, Franca, Brazil -
| | - Natália Y Noronha
- Department of Internal Medicine, Laboratory of Nutrigenomics Studies, Faculty of Medicine, University of São Paulo, Ribeirão Preto, Brazil
| | - Bruno A Oliveira
- Department of Internal Medicine, Laboratory of Nutrigenomics Studies, Faculty of Medicine, University of São Paulo, Ribeirão Preto, Brazil
| | - Flávia C Ferreira
- Department of Internal Medicine, Laboratory of Nutrigenomics Studies, Faculty of Medicine, University of São Paulo, Ribeirão Preto, Brazil
| | - Ana P Pinto
- Ribeirão Preto School of Physical Education and Sport, Laboratory of Exercise Physiology and Metabolism, University of São Paulo, Ribeirão Preto, Brazil
| | - Camila F Brandao
- Division of Nutrology, Department of Internal Medicine, Faculty of Medicine, University of São Paulo, Ribeirão Preto, Brazil.,State University of Minas Gerais, Divinópolis, Brazil
| | - Marcelo Papoti
- Ribeirão Preto School of Physical Education and Sport, Laboratory of Water Activities, University of São Paulo, Ribeirão Preto, Brazil
| | - Carla B Nonino
- Department of Internal Medicine, Laboratory of Nutrigenomics Studies, Faculty of Medicine, University of São Paulo, Ribeirão Preto, Brazil
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Effects of Beta-Alanine Supplementation on Physical Performance in Aerobic-Anaerobic Transition Zones: A Systematic Review and Meta-Analysis. Nutrients 2020; 12:nu12092490. [PMID: 32824885 PMCID: PMC7551186 DOI: 10.3390/nu12092490] [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: 07/13/2020] [Revised: 08/11/2020] [Accepted: 08/13/2020] [Indexed: 11/16/2022] Open
Abstract
Beta-alanine supplementation (BA) has a positive impact on physical performance. However, evidence showing a benefit of this amino acid in aerobic-anaerobic transition zones is scarce and the results controversial. The aim of this systematic review and meta-analysis is to analyze the effects of BA supplementation on physical performance in aerobic-anaerobic transition zones. At the same time, the effect of different dosages and durations of BA supplementation were identified. The search was designed in accordance with the PRISMA® guidelines for systematic reviews and meta-analyses and performed in Web of Science (WOS), Scopus, SPORTDiscus, PubMed, and MEDLINE between 2010 and 2020. The methodological quality and risk of bias were evaluated with the Cochrane Collaboration tool. The main variables were the Time Trial Test (TTT) and Time to Exhaustion (TTE) tests, the latter separated into the Limited Time Test (LTT) and Limited Distance Test (LDT). The analysis was carried out with a pooled standardized mean difference (SMD) through Hedges' g test (95% CI). Nineteen studies were included in the systematic review and meta-analysis, revealing a small effect for time in the TTT (SMD, -0.36; 95% CI, -0.87-0.16; I2 = 59%; p = 0.010), a small effect for LTT (SMD, 0.25; 95% CI, -0.01-0.51; I2 = 0%; p = 0.53), and a large effect for LDT (SMD, 4.27; 95% CI, -0.25-8.79; I2 = 94%; p = 0.00001). BA supplementation showed small effects on physical performance in aerobic-anaerobic transition zones. Evidence on acute supplementation is scarce (one study); therefore, exploration of acute supplementation with different dosages and formats on physical performance in aerobic-anaerobic transition zones is needed.
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Rothschild JA, Bishop DJ. Effects of Dietary Supplements on Adaptations to Endurance Training. Sports Med 2020; 50:25-53. [PMID: 31531769 DOI: 10.1007/s40279-019-01185-8] [Citation(s) in RCA: 30] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Endurance training leads to a variety of adaptations at the cellular and systemic levels that serve to minimise disruptions in whole-body homeostasis caused by exercise. These adaptations are differentially affected by training volume, training intensity, and training status, as well as by nutritional choices that can enhance or impair the response to training. A variety of supplements have been studied in the context of acute performance enhancement, but the effects of continued supplementation concurrent to endurance training programs are less well characterised. For example, supplements such as sodium bicarbonate and beta-alanine can improve endurance performance and possibly training adaptations during endurance training by affecting buffering capacity and/or allowing an increased training intensity, while antioxidants such as vitamin C and vitamin E may impair training adaptations by blunting cellular signalling but appear to have little effect on performance outcomes. Additionally, limited data suggest the potential for dietary nitrate (in the form of beetroot juice), creatine, and possibly caffeine, to further enhance endurance training adaptation. Therefore, the objective of this review is to examine the impact of dietary supplements on metabolic and physiological adaptations to endurance training.
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Affiliation(s)
- Jeffrey A Rothschild
- Sports Performance Research Institute New Zealand (SPRINZ), Auckland University of Technology, Auckland, New Zealand. .,TriFit Performance Center, Santa Monica, CA, USA.
| | - David J Bishop
- Institute for Health and Sport, Victoria University, Melbourne, VIC, Australia.,School of Medical and Health Sciences, Edith Cowan University, Joondalup, WA, Australia
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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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Lutsch DJ, Camic CL, Jagim AR, Johnston NJ, Musgjerd TL. Acute Effects of a Multi-Ingredient Pre-Workout Supplement On 5-KM Running Performance in Recreationally-Trained Athletes. INTERNATIONAL JOURNAL OF EXERCISE SCIENCE 2019; 12:1045-1056. [PMID: 31523345 PMCID: PMC6719810] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
The purpose of the present study was to examine the effects of an acute dose of a multi-ingredient pre-workout supplement on 5-km running performance and subjective measures of fatigue. Twenty aerobically-trained, males (n = 10, mean ± SD = 80.8 ± 6.1 kg) and females (n = 10, 64.5 ± 6.6 kg) completed two 5-km running races for time in a double-blind, cross-over fashion. During the first session, subjects were randomly assigned to ingest the supplement or placebo 30 minutes prior to running a 5-km race. The supplement contained multiple ingredients including caffeine anhydrous (150 mg), beta alanine (1.6 g), and arginine alpha-ketoglutarate (AKG) (1.0 g). Subjects also completed a 5-point Likert scale (1 = low, 5 = high) questionnaire to determine feelings of fatigue immediately prior to ingesting the substance (baseline), 30 minutes post-ingestion (immediately pre-race), and 5 minutes post-race. For the second session, subjects ingested the opposite substance (supplement or placebo) and underwent the same testing procedures (including time of day) as the first session. The results indicated there was no significant (p > 0.05) difference in 5-km race time between the supplement (23.62 ± 2.08 min) and placebo (23.51 ± 1.97 min) conditions. For the feelings of fatigue, there were no significant condition × time interactions or main effects for condition, but there were main effects for time. These findings indicated that the pre-workout supplement provided no ergogenic effect on 5-km race time or subjective feelings of fatigue when administered on an acute basis in aerobically-trained individuals.
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Affiliation(s)
- Daniel J Lutsch
- Department of Kinesiology and Physical Education, Northern Illinois University, DeKalb, Illinois, USA
| | - Clayton L Camic
- Department of Kinesiology and Physical Education, Northern Illinois University, DeKalb, Illinois, USA
| | | | - Nora J Johnston
- School of Sport and Exercise Science, University of Northern Colorado, Greeley, CO, USA
| | - Taylor L Musgjerd
- Physical Therapy Program, Department of Health Professions, University Wisconsin-La Crosse, La Crosse, WI, USA
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Nitrate Supplementation Combined with a Running Training Program Improved Time-Trial Performance in Recreationally Trained Runners. Sports (Basel) 2019; 7:sports7050120. [PMID: 31117193 PMCID: PMC6571712 DOI: 10.3390/sports7050120] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2019] [Revised: 05/10/2019] [Accepted: 05/16/2019] [Indexed: 11/30/2022] Open
Abstract
Our purpose was to verify the effects of inorganic nitrate combined to a short training program on 10-km running time-trial (TT) performance, maximum and average power on a Wingate test, and lactate concentration ([La−]) in recreational runners. Sixteen healthy participants were divided randomly into two groups: Nitrate (n = 8) and placebo (n = 8). The experimental group ingested 750 mg/day (~12 mmol) of nitrate plus 5 g of resistant starch, and the control group ingested 6 g of resistant starch, for 30 days. All variables were assessed at baseline and weekly over 30 days. Training took place 3x/week. The time on a 10-km TT decreased significantly (p < 0.001) in all timepoints compared to baseline in both groups, but only the nitrate group was faster in week 2 compared to 1. There was a significant group × time interaction (p < 0.001) with lower [La] in the nitrate group at week 2 (p = 0.032), week 3 (p = 0.002), and week 4 (p = 0.003). There was a significant group time interaction (p = 0.028) for Wingate average power and a main effect of time for maximum power (p < 0.001) and [La−] for the 60-s Wingate test. In conclusion, nitrate ingestion during a four-week running program improved 10-km TT performance and kept blood [La−] steady when compared to placebo in recreational runners.
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Beasley L, Smith L, Antonio J, Gordon D, Johnstone J, Roberts J. The effect of two β-alanine dosing strategies on 30-minute rowing performance: a randomized, controlled trial. J Int Soc Sports Nutr 2018; 15:59. [PMID: 30563538 PMCID: PMC6299666 DOI: 10.1186/s12970-018-0266-3] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2018] [Accepted: 11/27/2018] [Indexed: 11/12/2022] Open
Abstract
Background β-alanine (βA) supplementation has been shown to increase intramuscular carnosine content and subsequent high-intensity performance in events lasting < 4 minutes (min), which may be dependent on total, as opposed to daily, dose. The ergogenic effect of βA has also been demonstrated for 2000-m rowing performance prompting interest in whether βA may be beneficial for sustained aerobic exercise. This study therefore investigated the effect of two βA dosing strategies on 30-min rowing and subsequent sprint performance. Methods Following University Ethics approval, twenty-seven healthy, male rowers (age: 24 ± 2 years; body-height: 1.81 ± 0.02 m; body-mass: 82.3 ± 2.5 kg; body-fat: 14.2 ± 1.0%) were randomised in a double-blind manner to 4 weeks of: i) βA (2.4 g·d− 1, βA1); ii) matched total βA (4.8 g on alternate days, βA2); or iii) cornflour placebo (2.4 g·d− 1, PL). Participants completed a laboratory 30-min rowing time-trial, followed by 3x30-seconds (s) maximal sprint efforts at days 0, 14 and 28 (T1-T3). Total distance (m), average power (W), relative average power (W·kg− 1), cardio-respiratory measures and perceived exertion were assessed for each 10-min split. Blood lactate ([La-]b mmol·L− 1) was monitored pre-post time-trial and following maximal sprint efforts. A 3-way repeated measures ANOVA was employed for main analyses, with Bonferonni post-hoc assessment (P ≤ 0.05). Results Total 30-min time-trial distance significantly increased from T1-T3 within βA1 only (7397 ± 195 m to 7580 ± 171 m, P = 0.002, ƞp2 = 0.196), including absolute average power (194.8 ± 18.3 W to 204.2 ± 15.5 W, P = 0.04, ƞp2 = 0.115) and relative average power output (2.28 ± 0.15 W·kg− 1 to 2.41 ± 0.12 W·kg− 1, P = 0.031, ƞp2 = 0.122). These findings were potentially explained by within-group significance for the same variables for the first 10 min split (P ≤ 0.01), and for distance covered (P = 0.01) in the second 10-min split. However, no condition x time interactions were observed. No significant effects were found for sprint variables (P > 0.05) with comparable values at T3 for mean distance (βA1: 163.9 ± 3.8 m; βA2: 161.2 ± 3.5 m; PL: 162.7 ± 3.6 m), average power (βA1: 352.7 ± 14.5 W; βA2: 342.2 ± 13.5 W; PL: 348.2 ± 13.9 W) and lactate (βA1: 10.0 ± 0.9 mmol·L− 1; βA2: 9.2 ± 1.1 mmol·L− 1; PL: 8.7 ± 0.9 mmol·L− 1). Conclusions Whilst daily βA may confer individual benefits, these results demonstrate limited impact of βA (irrespective of dosing strategy) on 30-min rowing or subsequent sprint performance. Further investigation of βA dosage > 2.4 g·d− 1 and/or chronic intervention periods (> 4–8 weeks) may be warranted based on within-group observations.
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Affiliation(s)
- Liam Beasley
- Cambridge Centre for Sport and Exercise Sciences, Anglia Ruskin University, Cambridge, UK
| | - Lee Smith
- Cambridge Centre for Sport and Exercise Sciences, Anglia Ruskin University, Cambridge, UK
| | - Jose Antonio
- College of Health Care Sciences, Nova Southeastern University, Florida, USA
| | - Dan Gordon
- Cambridge Centre for Sport and Exercise Sciences, Anglia Ruskin University, Cambridge, UK
| | - James Johnstone
- Cambridge Centre for Sport and Exercise Sciences, Anglia Ruskin University, Cambridge, UK
| | - Justin Roberts
- Cambridge Centre for Sport and Exercise Sciences, Anglia Ruskin University, Cambridge, UK.
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