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Álvarez-Herms J. Summatory Effects of Anaerobic Exercise and a 'Westernized Athletic Diet' on Gut Dysbiosis and Chronic Low-Grade Metabolic Acidosis. Microorganisms 2024; 12:1138. [PMID: 38930520 PMCID: PMC11205432 DOI: 10.3390/microorganisms12061138] [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: 04/14/2024] [Revised: 05/27/2024] [Accepted: 05/28/2024] [Indexed: 06/28/2024] Open
Abstract
Anaerobic exercise decreases systemic pH and increases metabolic acidosis in athletes, altering the acid-base homeostasis. In addition, nutritional recommendations advising athletes to intake higher amounts of proteins and simple carbohydrates (including from sport functional supplements) could be detrimental to restoring acid-base balance. Here, this specific nutrition could be classified as an acidic diet and defined as 'Westernized athletic nutrition'. The maintenance of a chronic physiological state of low-grade metabolic acidosis produces detrimental effects on systemic health, physical performance, and inflammation. Therefore, nutrition must be capable of compensating for systemic acidosis from anaerobic exercise. The healthy gut microbiota can contribute to improving health and physical performance in athletes and, specifically, decrease the systemic acidic load through the conversion of lactate from systemic circulation to short-chain fatty acids in the proximal colon. On the contrary, microbial dysbiosis results in negative consequences for host health and physical performance because it results in a greater accumulation of systemic lactate, hydrogen ions, carbon dioxide, bacterial endotoxins, bioamines, and immunogenic compounds that are transported through the epithelia into the blood circulation. In conclusion, the systemic metabolic acidosis resulting from anaerobic exercise can be aggravated through an acidic diet, promoting chronic, low-grade metabolic acidosis in athletes. The individuality of athletic training and nutrition must take into consideration the acid-base homeostasis to modulate microbiota and adaptive physiological responses.
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Affiliation(s)
- Jesús Álvarez-Herms
- Phymolab, Physiology and Molecular Laboratory, 40170 Collado Hermoso, Segovia, Spain
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de Oliveira LF, Dolan E, Swinton PA, Durkalec-Michalski K, Artioli GG, McNaughton LR, Saunders B. Extracellular Buffering Supplements to Improve Exercise Capacity and Performance: A Comprehensive Systematic Review and Meta-analysis. Sports Med 2022; 52:505-526. [PMID: 34687438 DOI: 10.1007/s40279-021-01575-x] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/23/2021] [Indexed: 02/05/2023]
Abstract
BACKGROUND Extracellular buffering supplements [sodium bicarbonate (SB), sodium citrate (SC), sodium/calcium lactate (SL/CL)] are ergogenic supplements, although questions remain about factors which may modify their effect. OBJECTIVE To quantify the main effect of extracellular buffering agents on exercise outcomes, and to investigate the influence of potential moderators on this effect using a systematic review and meta-analytic approach. METHODS This study was designed in accordance with Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Three databases were searched for articles that were screened according to inclusion/exclusion criteria. Bayesian hierarchical meta-analysis and meta-regression models were used to investigate pooled effects of supplementation and moderating effects of a range of factors on exercise and biomarker responses. RESULTS 189 articles with 2019 participants were included, 158 involving SB supplementation, 30 with SC, and seven with CL/SL; four studies provided a combination of buffering supplements together. Supplementation led to a mean estimated increase in blood bicarbonate of + 5.2 mmol L-1 (95% credible interval (CrI) 4.7-5.7). The meta-analysis models identified a positive overall effect of supplementation on exercise capacity and performance compared to placebo [ES0.5 = 0.17 (95% CrI 0.12-0.21)] with potential moderating effects of exercise type and duration, training status and when the exercise test was performed following prior exercise. The greatest ergogenic effects were shown for exercise durations of 0.5-10 min [ES0.5 = 0.18 (0.13-0.24)] and > 10 min [ES0.5 = 0.22 (0.10-0.33)]. Evidence of greater effects on exercise were obtained when blood bicarbonate increases were medium (4-6 mmol L-1) and large (> 6 mmol L-1) compared with small (≤ 4 mmol L-1) [βSmall:Medium = 0.16 (95% CrI 0.02-0.32), βSmall:Large = 0.13 (95% CrI - 0.03 to 0.29)]. SB (192 outcomes) was more effective for performance compared to SC (39 outcomes) [βSC:SB = 0.10 (95% CrI - 0.02 to 0.22)]. CONCLUSIONS Extracellular buffering supplements generate large increases in blood bicarbonate concentration leading to positive overall effects on exercise, with sodium bicarbonate being most effective. Evidence for several group-level moderating factors were identified. These data can guide an athlete's decision as to whether supplementation with buffering agents might be beneficial for their specific aims.
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Affiliation(s)
- Luana Farias de Oliveira
- Applied Physiology & Nutrition Research Group, Rheumatology Division, Faculty of Medicine FMUSP, University of São Paulo, São Paulo, Brazil
| | - Eimear Dolan
- Applied Physiology & Nutrition Research Group, Rheumatology Division, Faculty of Medicine FMUSP, University of São Paulo, São Paulo, Brazil
| | - Paul A Swinton
- School of Health Sciences, Robert Gordon University, Aberdeen, UK
| | - Krzysztof Durkalec-Michalski
- Department of Sports Dietetics, Poznań University of Physical Education, Poznań, Poland
- Department of Human Nutrition and Dietetics, Poznań University of Life Sciences, Poznań, Poland
| | - Guilherme G Artioli
- Department of Life Sciences, Manchester Metropolitan University, John Dalton Building, Manchester, M1 5GD, UK
| | - Lars R McNaughton
- Sports Nutrition and Performance Group, Department of Sport and Physical Activity, Edge Hill University, Ormskirk, UK
| | - Bryan Saunders
- Applied Physiology & Nutrition Research Group, Rheumatology Division, Faculty of Medicine FMUSP, University of São Paulo, São Paulo, Brazil.
- Department of Sports Dietetics, Poznań University of Physical Education, Poznań, Poland.
- Institute of Orthopaedics and Traumatology, Faculty of Medicine FMUSP, University of São Paulo, São Paulo, Brazil.
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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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Limmer M, Eibl AD, Platen P. Enhanced 400-m sprint performance in moderately trained participants by a 4-day alkalizing diet: a counterbalanced, randomized controlled trial. J Int Soc Sports Nutr 2018; 15:25. [PMID: 29855319 PMCID: PMC5984464 DOI: 10.1186/s12970-018-0231-1] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2017] [Accepted: 05/25/2018] [Indexed: 01/11/2023] Open
Abstract
Background Sodium bicarbonate (NaHCO3) is an alkalizing agent and its ingestion is used to improve anaerobic performance. However, the influence of alkalizing nutrients on anaerobic exercise performance remains unclear. Therefore, the present study investigated the influence of an alkalizing versus acidizing diet on 400-m sprint performance, blood lactate, blood gas parameters, and urinary pH in moderately trained adults. Methods In a randomized crossover design, eleven recreationally active participants (8 men, 3 women) aged 26.0 ± 1.7 years performed one trial under each individual’s unmodified diet and subsequently two trials following either 4 days of an alkalizing (BASE) or acidizing (ACID) diet. Trials consisted of 400-m runs at intervals of 1 week on a tartan track in a randomized order. Results We found a significantly lower 400-m performance time for the BASE trial (65.8 ± 7.2 s) compared with the ACID trial (67.3 ± 7.1 s; p = 0.026). In addition, responses were significantly higher following the BASE diet for blood lactate (BASE: 16.3 ± 2.7; ACID: 14.4 ± 2.1 mmol/L; p = 0.32) and urinary pH (BASE: 7.0 ± 0.7; ACID: 5.5 ± 0.7; p = 0.001). Conclusions We conclude that a short-term alkalizing diet may improve 400-m performance time in moderately trained participants. Additionally, we found higher blood lactate concentrations under the alkalizing diet, suggesting an enhanced blood or muscle buffer capacity. Thus, an alkalizing diet may be an easy and natural way to enhance 400-m sprint performance for athletes without the necessity of taking artificial dietary supplements.
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Affiliation(s)
- Mirjam Limmer
- Department of Sports Medicine and Sports Nutrition, Ruhr-University Bochum, Gesundheitscampus Nord 10, 44801, Bochum, Germany. .,Institute of Outdoor Sports and Environmental Science, German Sports University Cologne, Cologne, Germany.
| | - Angi Diana Eibl
- Department of Sports Medicine and Sports Nutrition, Ruhr-University Bochum, Gesundheitscampus Nord 10, 44801, Bochum, Germany
| | - Petra Platen
- Department of Sports Medicine and Sports Nutrition, Ruhr-University Bochum, Gesundheitscampus Nord 10, 44801, Bochum, Germany
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Wroble KA, Trott MN, Schweitzer GG, Rahman RS, Kelly PV, Weiss EP. Low-carbohydrate, ketogenic diet impairs anaerobic exercise performance in exercise-trained women and men: a randomized-sequence crossover trial. J Sports Med Phys Fitness 2018; 59:600-607. [PMID: 29619799 DOI: 10.23736/s0022-4707.18.08318-4] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
BACKGROUND Low-carbohydrate, ketogenic diets cause mild, subclinical systemic acidosis. Anaerobic exercise performance is limited by acidosis. Therefore, we evaluated the hypothesis that a low-carbohydrate, ketogenic diet impairs anaerobic exercise performance, as compared to a high-carbohydrate diet. METHODS Sixteen men and women (BMI, 23±1 kg/m2, age 23±1 years) participated in a randomized-sequence, counterbalanced crossover study in which they underwent exercise testing after 4 days of either a low-carbohydrate, ketogenic diet (LC; <50 g/day and <10% of energy from carbohydrates) or a high-carbohydrate diet (HC; 6-10 g/kg/day carbohydrate). Dietary compliance was assessed with nutrient analysis of diet records, and with measures of urine pH and ketones. Anaerobic exercise performance was evaluated with the Wingate anaerobic cycling test and the yo-yo intermittent recovery test. RESULTS The diets were matched for total energy (LC: 2333±158 kcal/d; HC: 2280±160 kcal/d; P=0.65) but differed in carbohydrate content (9±1% vs. 63±2% of energy intake; P<0.001). LC resulted in lower urine pH (5.9±0.1 vs. 6.3±0.2, P=0.004) and the appearance of urine ketones in every participant. LC resulted in 7% lower peak power (801±58 watts vs. 857±61 watts, P=0.008) and 6% lower mean power (564±50 watts vs. 598±51 watts, P=0.01) during the Wingate Test. Total distance ran in the yo-yo intermittent recovery test was 15% less after LC diet (887±139 vs. 1045±145 meters, P=0.02). CONCLUSIONS Short-term low-carbohydrate, ketogenic diets reduce exercise performance in activities that are heavily dependent on anaerobic energy systems. These findings have clear performance implications for athletes, especially for high-intensity, short duration activities and sports.
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Affiliation(s)
- Kymberly A Wroble
- Department of Nutrition and Dietetics, Saint Louis University, St. Louis, MO, USA
| | - Morgan N Trott
- Department of Nutrition and Dietetics, Saint Louis University, St. Louis, MO, USA
| | - George G Schweitzer
- Department of Nutrition and Dietetics, Saint Louis University, St. Louis, MO, USA.,Division of Geriatrics and Nutritional Science, Washington University School of Medicine, St. Louis, MO, USA
| | - Rabia S Rahman
- Department of Nutrition and Dietetics, Saint Louis University, St. Louis, MO, USA
| | - Patrick V Kelly
- Doisy College of Health Sciences, Saint Louis University, St. Louis, MO, USA
| | - Edward P Weiss
- Department of Nutrition and Dietetics, Saint Louis University, St. Louis, MO, USA - .,Doisy College of Health Sciences, Saint Louis University, St. Louis, MO, USA
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Carr AJ, Sharma AP, Ross ML, Welvaert M, Slater GJ, Burke LM. Chronic Ketogenic Low Carbohydrate High Fat Diet Has Minimal Effects on Acid-Base Status in Elite Athletes. Nutrients 2018; 10:E236. [PMID: 29463034 PMCID: PMC5852812 DOI: 10.3390/nu10020236] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2018] [Revised: 02/12/2018] [Accepted: 02/13/2018] [Indexed: 02/07/2023] Open
Abstract
Although short (up to 3 days) exposure to major shifts in macronutrient intake appears to alter acid-base status, the effects of sustained (>1 week) interventions in elite athletes has not been determined. Using a non-randomized, parallel design, we examined the effect of adaptations to 21 days of a ketogenic low carbohydrate high fat (LCHF) or periodized carbohydrate (PCHO) diet on pre- and post-exercise blood pH, and concentrations of bicarbonate (HCO₃-) and lactate (La-) in comparison to a high carbohydrate (HCHO) control. Twenty-four (17 male and 7 female) elite-level race walkers completed 21 days of either LCHF (n = 9), PCHO (n = 7), or HCHO (n = 8) under controlled diet and training conditions. At baseline and post-intervention, blood pH, blood [HCO₃-], and blood [La-] were measured before and after a graded exercise test. Net endogenous acid production (NEAP) over the previous 48-72 h was also calculated from monitored dietary intake. LCHF was not associated with significant differences in blood pH, [HCO₃-], or [La-], compared with the HCHO diet pre- or post-exercise, despite a significantly higher NEAP (mEq·day-1) (95% CI = [10.44; 36.04]). Our results indicate that chronic dietary interventions are unlikely to influence acid-base status in elite athletes, which may be due to pre-existing training adaptations, such as an enhanced buffering capacity, or the actions of respiratory and renal pathways, which have a greater influence on regulation of acid-base status than nutritional intake.
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Affiliation(s)
- Amelia J Carr
- Centre for Sport Research, Deakin University, Burwood VIC 3125, Australia.
| | - Avish P Sharma
- Physiology, Australian Institute of Sport, Bruce ACT 2617, Australia.
- Research Institute for Sport and Exercise, University of Canberra, Belconnen ACT 2616, Australia.
| | - Megan L Ross
- Sports Nutrition, Australian Institute of Sport, Bruce ACT 2617, Australia.
- Mary MacKillop Institute for Health Research, Australian Catholic University, Melbourne VIC 3000, Australia.
| | - Marijke Welvaert
- Research Institute for Sport and Exercise, University of Canberra, Belconnen ACT 2616, Australia.
- Innovation, Research and Development, Australian Institute of Sport, Bruce ACT 2617, Australia.
| | - Gary J Slater
- School of Health and Sport Sciences, University of the Sunshine Coast, Maroochydore QLD 4558, Australia.
| | - Louise M Burke
- Sports Nutrition, Australian Institute of Sport, Bruce ACT 2617, Australia.
- Mary MacKillop Institute for Health Research, Australian Catholic University, Melbourne VIC 3000, Australia.
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Remer T, Krupp D, Shi L. Dietary protein's and dietary acid load's influence on bone health. Crit Rev Food Sci Nutr 2014; 54:1140-50. [PMID: 24499146 DOI: 10.1080/10408398.2011.627519] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
A variety of genetic, mechano-response-related, endocrine-metabolic, and nutritional determinants impact bone health. Among the nutritional influences, protein intake and dietary acid load are two of the factors most controversially discussed. Although in the past high protein intake was often assumed to exert a primarily detrimental impact on bone mass and skeletal health, the majority of recent studies indicates the opposite and suggests a bone-anabolic influence. Studies examining the influence of alkalizing diets or alkalizing supplement provision on skeletal outcomes are less consistent, which raises doubts about the role of acid-base status in bone health. The present review critically evaluates relevant key issues such as acid-base terminology, influencing factors of intestinal calcium absorption, calcium balance, the endocrine-metabolic milieu related to metabolic acidosis, and some methodological aspects of dietary exposure and bone outcome examinations. It becomes apparent that for an adequate identification and characterization of either dietary acid load's or protein's impact on bone, the combined assessment of both nutritional influences is necessary.
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Affiliation(s)
- Thomas Remer
- a IEL-Nutritional Epidemiology, University of Bonn, DONALD Study at the Research Institute of Child Nutrition , Dortmund , Germany
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Lambert CP, Winchester L, Jacks DA, Nader PA. Sex differences in time to fatigue at 100% VO2 peak when normalized for fat free mass. Res Sports Med 2013; 21:78-89. [PMID: 23286424 DOI: 10.1080/15438627.2012.697809] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
Abstract
The purpose of this investigation was to compare sexes for time to fatigue at 100% VO(2)peak in recreationally trained individuals. Ten men (age: 23.4 ± 1.8; height: 177 ± 6.7; body mass: 83.8 ± 11.3; ± SD) and nine women (age: 25.0 ± 2.5; height: 165.6 ± 5.5; body mass: 62.7 ± 6.7) participated in this investigation after providing written consent. One week after assessing VO(2)peak, subjects exercised on an electrically braked cycle ergometer at 100% of VO(2)peak until fatigue. The time taken to fatigue was 48.9% longer for men than women (274 ± 13s vs. 184 ± 14s; p < 0.001, for men and women, respectively). When normalized for fat free mass (ffm; s/kg ffm) no significant differences between men and women were observed (3.99 ± 0.21s/kg ffm vs. 3.72 ± 0.28s/kg ffm for men and women, respectively, p = 0.431). The difference in fatigability between the sexes at this exercise intensity is to a large degree related to the difference in fat free mass.
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Affiliation(s)
- Charles P Lambert
- The Exercise Physiology Laboratory, University of Louisville, Louisville, Kentucky, USA.
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Abstract
The concept of diet-induced ‘acidosis’ as a cause of disease has been a subject of interest for more than a century. The present article reviews the history of our evolving understanding of physiological pH, the physiological support for the concept of ‘acidosis’, the causes of acidosis, how it is recognised, its short-term effects as well as the long-term clinical relevance of preventative measures, and the research support for normalisation of pH. Further, we suggest differentiation of the terms ‘acidosis’ and ‘acidaemia’ as a way to resolve the conflation of these topics which has led to confusion and controversy. The available research makes a compelling case that diet-induced acidosis, not diet-induced acidaemia, is a real phenomenon, and has a significant, clinical, long-term pathophysiological effect that should be recognised and potentially counterbalanced by dietary means.
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Degoutte F, Jouanel P, Filaire E. Mise en évidence de la sollicitation du cycle des purines nucléotides lors d’un combat de judo. Sci Sports 2004. [DOI: 10.1016/s0765-1597(03)00162-x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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Ozmerdivenli R, Baysal B, Karacabey K, Saygin O. Comparison of the Effect of Sodium Bicarbonate use on the Performace of Athletes and Non-Athletes. BIOTECHNOL BIOTEC EQ 2004. [DOI: 10.1080/13102818.2004.10817143] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022] Open
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Nielsen HB, Bredmose PP, Strømstad M, Volianitis S, Quistorff B, Secher NH. Bicarbonate attenuates arterial desaturation during maximal exercise in humans. J Appl Physiol (1985) 2002; 93:724-31. [PMID: 12133884 DOI: 10.1152/japplphysiol.00398.2000] [Citation(s) in RCA: 76] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The contribution of pH to exercise-induced arterial O2 desaturation was evaluated by intravenous infusion of sodium bicarbonate (Bic, 1 M; 200-350 ml) or an equal volume of saline (Sal; 1 M) at a constant infusion rate during a "2,000-m" maximal ergometer row in five male oarsmen. Blood-gas variables were corrected to the increase in blood temperature from 36.5 +/- 0.3 to 38.9 +/- 0.1 degrees C (P < 0.05; means +/- SE), which was established in a pilot study. During Sal exercise, pH decreased from 7.42 +/- 0.01 at rest to 7.07 +/- 0.02 but only to 7.34 +/- 0.02 (P < 0.05) during the Bic trial. Arterial PO2 was reduced from 103.1 +/- 0.7 to 88.2 +/- 1.3 Torr during exercise with Sal, and this reduction was not significantly affected by Bic. Arterial O2 saturation was 97.5 +/- 0.2% at rest and decreased to 89.0 +/- 0.7% during Sal exercise but only to 94.1 +/- 1% with Bic (P < 0.05). Arterial PCO2 was not significantly changed from resting values in the last minute of Sal exercise, but in the Bic trial it increased from 40.5 +/- 0.5 to 45.9 +/- 2.0 Torr (P < 0.05). Pulmonary ventilation was lowered during exercise with Bic (155 +/- 14 vs. 142 +/- 13 l/min; P < 0.05), but the exercise-induced increase in the difference between the end-tidal O2 pressure and arterial PO2 was similar in the two trials. Also, pulmonary O2 uptake and changes in muscle oxygenation as determined by near-infrared spectrophotometry during exercise were similar. The enlarged blood-buffering capacity after infusion of Bic attenuated acidosis and in turn arterial desaturation during maximal exercise.
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Affiliation(s)
- Henning B Nielsen
- The Copenhagen Muscle Research Center, Department of Anesthesia, Rigshospitalet, DK-2100 Copenhagen, Denmark.
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