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Blackwood SJ, Katz A. Isoproterenol enhances force production in mouse glycolytic and oxidative muscle via separate mechanisms. Pflugers Arch 2019; 471:1305-1316. [PMID: 31451903 PMCID: PMC6814637 DOI: 10.1007/s00424-019-02304-0] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2019] [Revised: 07/22/2019] [Accepted: 08/13/2019] [Indexed: 02/04/2023]
Abstract
Fight or flight is a biologic phenomenon that involves activation of β-adrenoceptors in skeletal muscle. However, how force generation is enhanced through adrenergic activation in different muscle types is not fully understood. We studied the effects of isoproterenol (ISO, β-receptor agonist) on force generation and energy metabolism in isolated mouse soleus (SOL, oxidative) and extensor digitorum longus (EDL, glycolytic) muscles. Muscles were stimulated with isometric tetanic contractions and analyzed for metabolites and phosphorylase activity. Under conditions of maximal force production, ISO enhanced force generation markedly more in SOL (22%) than in EDL (8%). Similarly, during a prolonged tetanic contraction (30 s for SOL and 10 s for EDL), ISO-enhanced the force × time integral more in SOL (25%) than in EDL (3%). ISO induced marked activation of phosphorylase in both muscles in the basal state, which was associated with glycogenolysis (less in SOL than in EDL), and in EDL only, a significant decrease (16%) in inorganic phosphate (Pi). ATP turnover during sustained contractions (1 s EDL, 5 s SOL) was not affected by ISO in EDL, but essentially doubled in SOL. Under conditions of maximal stimulation, ISO has a minor effect on force generation in EDL that is associated with a decrease in Pi, whereas ISO has a marked effect on force generation in SOL that is associated with an increase in ATP turnover. Thus, phosphorylase functions as a phosphate trap in ISO-mediated force enhancement in EDL and as a catalyzer of ATP supply in SOL.
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Affiliation(s)
- Sarah J Blackwood
- Åstrand Laboratory of Work Physiology, Swedish School of Sport and Health Sciences, GIH, Box 5626, S-114 86, Stockholm, Sweden
| | - Abram Katz
- Åstrand Laboratory of Work Physiology, Swedish School of Sport and Health Sciences, GIH, Box 5626, S-114 86, Stockholm, Sweden.
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2
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Tallis J, Higgins MF, Cox VM, Duncan MJ, James RS. An exercise-induced improvement in isolated skeletal muscle contractility does not affect the performance-enhancing benefit of 70 µmol l -1 caffeine treatment. ACTA ACUST UNITED AC 2018; 221:jeb.190132. [PMID: 30224369 DOI: 10.1242/jeb.190132] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2018] [Accepted: 09/11/2018] [Indexed: 11/20/2022]
Abstract
This study aimed to examine the effects of exercise-induced increases in skeletal muscle contractile performance on isolated skeletal muscle caffeine sensitivity in mice. CD1 mice (n=28; 30 weeks old) either served as controls or underwent 8 weeks of voluntary wheel running. Following the treatment intervention, whole soleus (SOL) or a section of the costal diaphragm (DIA) was isolated from each mouse and tested to determine the effect of 70 µmol l-1 caffeine on work loop power output. Although caffeine elicited a significant increase in power of both the SOL and the DIA relative to levels in a non-caffeine-treated control, the effect was not different between the experimental groups, despite the muscles of the trained group producing significantly greater muscle power. There was no significant relationship between training volume or baseline work loop power and the caffeine response. These results indicate that an exercise-induced increase in muscle performance did not influence the performance-enhancing effects of caffeine.
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Affiliation(s)
- Jason Tallis
- Centre for Sport, Exercise and Life Sciences, Alison Gingell Building, Coventry University, Priory Street, Coventry CV1 5FB, UK
| | - Matthew F Higgins
- Department of Life Sciences, Sport, Outdoor and Exercise Science, Derby University, Kedleston Road, Derby DE22 1GB, UK
| | - Val M Cox
- Centre for Sport, Exercise and Life Sciences, Alison Gingell Building, Coventry University, Priory Street, Coventry CV1 5FB, UK
| | - Michael J Duncan
- Centre for Sport, Exercise and Life Sciences, Alison Gingell Building, Coventry University, Priory Street, Coventry CV1 5FB, UK
| | - Rob S James
- Centre for Sport, Exercise and Life Sciences, Alison Gingell Building, Coventry University, Priory Street, Coventry CV1 5FB, UK
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3
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Acute attenuation of fatigue after sodium bicarbonate supplementation does not manifest into greater training adaptations after 10-weeks of resistance training exercise. PLoS One 2018; 13:e0196677. [PMID: 29718968 PMCID: PMC5931633 DOI: 10.1371/journal.pone.0196677] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2017] [Accepted: 04/17/2018] [Indexed: 01/24/2023] Open
Abstract
PURPOSE In two concurrent studies, we aimed to a) confirm the acute effect of 0.3 g·kg-1 body weight (BW) sodium bicarbonate (NaHCO3) supplementation on central and peripheral mechanisms associated with explosive power (Study 1) and b) determine whether chronic NaHCO3 supplementation would improve the adaptive response of the neuromuscular system during a 10-week resistance training program (Study 2). METHODS Eight resistance trained participants volunteered after providing written consent. The experimental design consisted of a week of baseline testing, followed by ten weeks of training with progress measures performed in Week 5. Study 1 involved neuromuscular measurements before and after the leg extension portion of a power based training session performed in Week 1. Changes in maximal torque (MVT) and rates of torque development (RTD), along with other variables derived from femoral nerve stimulation (e.g. voluntary activation, neural recruitment) were analysed to determine the extent of fatigue under NaHCO3 or placebo conditions. Changes in these same variables, coupled with functional 1-repetition maximum leg extension strength, were measured in Study 2 from baseline (Week 0) to Week 5, and again at Week 10. RESULTS AND CONCLUSION In Study 1, we observed a decline after the leg extension task in both MVT (~ 30%) and rates of torque production (RTD) irrespective of acid-base status, however the decline in maximal RTD (RTDMAX) was nearly 20% less in the NaHCO3 condition when compared to placebo (mean difference of 294.8 ± 133.4 Nm·s-1 (95% CI -583.1 to -6.5 Nm, p < 0.05)). The primary finding in Study 2, however, suggests that introducing NaHCO3 repeatedly during a 10-week RT program does not confer any additional benefit to the mechanisms (and subsequent adaptive processes) related to explosive power production.
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Siegler JC, Mudie K, Marshall P. The influence of sodium bicarbonate on maximal force and rates of force development in the triceps surae and brachii during fatiguing exercise. Exp Physiol 2017; 101:1383-1391. [PMID: 27634487 DOI: 10.1113/ep085933] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2016] [Accepted: 09/13/2016] [Indexed: 11/08/2022]
Abstract
NEW FINDINGS What is the central question of this study? Does metabolic alkalosis in humans, induced by sodium bicarbonate, affect rates of skeletal muscle fatigue differentially in muscle groups composed predominately of slow- and fast-twitch fibres? What is the main finding and its importance? Sodium bicarbonate exhibited no effect on the fatigue profile observed between triceps surae and brachii muscle groups during and after 2 min of tetanic stimulation. For the first time in exercising humans, we have profiled the effect of sodium bicarbonate on the voluntary and involuntary contractile characteristics of muscle groups representative of predominately slow- and fast-twitch fibres. The effect of metabolic alkalosis on fibre-specific maximal force production and rates of force development (RFD) has been investigated previously in animal models, with evidence suggesting an improved capacity to develop force rapidly in fast- compared with slow-twitch muscle. We have attempted to model in vivo the fatigue profile of voluntary and involuntary maximal force and RFD in the triceps surae and brachii after sodium bicarbonate (NaHCO3 ) ingestion. In a double-blind, three-way repeated-measures design, participants (n = 10) ingested either 0.3 g kg-1 NaHCO3 (ALK) or equivalent calcium carbonate (PLA) prior to 2 min of continuous (1 Hz) supramaximal stimulation (300 ms at 40 Hz) of the triceps surae or brachii, with maximal voluntary efforts (maximal voluntary torque) coupled with direct muscle stimulation also measured at baseline, 1 and 2 min. Metabolic alkalosis was achieved in both ALK trials but was not different between muscle groups. Regardless of the conditions, involuntary torque declined nearly 60% in the triceps brachii (P < 0.001) and ∼30% in the triceps surae (P < 0.001). In all trials, there was a significant decline in normalized involuntary RFD (P < 0.05). Maximal voluntary torque declined nearly 28% but was not different between conditions (P < 0.01), and although declining nearly 21% in voluntary RFD (P < 0.05) there was no difference between PLA and ALK in either muscle group (P = 0.93). Sodium bicarbonate exhibited no effect on the fatigue observed between representative fibre-type muscle groups on maximal voluntary and involuntary torque or rates of torque development during and after 2 min of tetanic stimulation.
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Affiliation(s)
- Jason C Siegler
- Sport and Exercise Science, School of Science and Health, Western Sydney University, Sydney, New South Wales, Australia.
| | - Kurt Mudie
- Sport and Exercise Science, School of Science and Health, Western Sydney University, Sydney, New South Wales, Australia.,Institute of Sport, Exercise and Active Living (ISEAL), Victoria University, Melbourne, Victoria, Australia
| | - Paul Marshall
- Sport and Exercise Science, School of Science and Health, Western Sydney University, Sydney, New South Wales, Australia
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5
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The relationship between oxygen uptake kinetics and neuromuscular fatigue in high-intensity cycling exercise. Eur J Appl Physiol 2017; 117:969-978. [DOI: 10.1007/s00421-017-3585-1] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2017] [Accepted: 03/06/2017] [Indexed: 10/19/2022]
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Siegler JC, Marshall PWM, Bishop D, Shaw G, Green S. Mechanistic Insights into the Efficacy of Sodium Bicarbonate Supplementation to Improve Athletic Performance. SPORTS MEDICINE-OPEN 2016; 2:41. [PMID: 27747796 PMCID: PMC5059234 DOI: 10.1186/s40798-016-0065-9] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/13/2016] [Accepted: 09/20/2016] [Indexed: 01/13/2023]
Abstract
A large proportion of empirical research and reviews investigating the ergogenic potential of sodium bicarbonate (NaHCO3) supplementation have focused predominately on performance outcomes and only speculate about underlying mechanisms responsible for any benefit. The aim of this review was to critically evaluate the influence of NaHCO3 supplementation on mechanisms associated with skeletal muscle fatigue as it translates directly to exercise performance. Mechanistic links between skeletal muscle fatigue, proton accumulation (or metabolic acidosis) and NaHCO3 supplementation have been identified to provide a more targeted, evidence-based approach to direct future research, as well as provide practitioners with a contemporary perspective on the potential applications and limitations of this supplement. The mechanisms identified have been broadly categorised under the sections ‘Whole-body Metabolism’, ‘Muscle Physiology’ and ‘Motor Pathways’, and when possible, the performance outcomes of these studies contextualized within an integrative framework of whole-body exercise where other factors such as task demand (e.g. large vs. small muscle groups), cardio-pulmonary and neural control mechanisms may outweigh any localised influence of NaHCO3. Finally, the ‘Performance Applications’ section provides further interpretation for the practitioner founded on the mechanistic evidence provided in this review and other relevant, applied NaHCO3 performance-related studies.
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Affiliation(s)
- Jason C Siegler
- School of Science and Health, Sport and Exercise Science, Western Sydney University, Locked Bag 1792, Penrith, NSW, Australia.
| | - Paul W M Marshall
- School of Science and Health, Sport and Exercise Science, Western Sydney University, Locked Bag 1792, Penrith, NSW, Australia
| | - David Bishop
- Institute of Sport, Exercise and Active Living (ISEAL), Victoria University, Melbourne, Australia
| | - Greg Shaw
- Australian Institute of Sport, Canberra, Australia
| | - Simon Green
- School of Science and Health, Sport and Exercise Science, Western Sydney University, Locked Bag 1792, Penrith, NSW, Australia.,School of Medicine, Western Sydney University, Sydney, Australia
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Higgins MF, Wilson S, Hill C, Price MJ, Duncan M, Tallis J. Evaluating the effects of caffeine and sodium bicarbonate, ingested individually or in combination, and a taste-matched placebo on high-intensity cycling capacity in healthy males. Appl Physiol Nutr Metab 2016; 41:354-61. [PMID: 26988768 DOI: 10.1139/apnm-2015-0371] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
This study evaluated the effects of ingesting sodium bicarbonate (NaHCO3) or caffeine individually or in combination on high-intensity cycling capacity. In a counterbalanced, crossover design, 13 healthy, noncycling trained males (age: 21 ± 3 years, height: 178 ± 6 cm, body mass: 76 ± 12 kg, peak power output (Wpeak): 230 ± 34 W, peak oxygen uptake: 46 ± 8 mL·kg(-1)·min(-1)) performed a graded incremental exercise test, 2 familiarisation trials, and 4 experimental trials. Trials consisted of cycling to volitional exhaustion at 100% Wpeak (TLIM) 60 min after ingesting a solution containing either (i) 0.3 g·kg(-1) body mass sodium bicarbonate (BIC), (ii) 5 mg·kg(-1) body mass caffeine plus 0.1 g·kg(-1) body mass sodium chloride (CAF), (iii) 0.3 g·kg(-1) body mass sodium bicarbonate plus 5 mg·kg(-1) body mass caffeine (BIC-CAF), or (iv) 0.1 g·kg(-1) body mass sodium chloride (PLA). Experimental solutions were administered double-blind. Pre-exercise, at the end of exercise, and 5-min postexercise blood pH, base excess, and bicarbonate ion concentration ([HCO3(-)]) were significantly elevated for BIC and BIC-CAF compared with CAF and PLA. TLIM (median; interquartile range) was significantly greater for CAF (399; 350-415 s; P = 0.039; r = 0.6) and BIC-CAF (367; 333-402 s; P = 0.028; r = 0.6) compared with BIC (313: 284-448 s) although not compared with PLA (358; 290-433 s; P = 0.249, r = 0.3 and P = 0.099 and r = 0.5, respectively). There were no differences between PLA and BIC (P = 0.196; r = 0.4) or between CAF and BIC-CAF (P = 0.753; r = 0.1). Relatively large inter- and intra-individual variation was observed when comparing treatments and therefore an individual approach to supplementation appears warranted.
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Affiliation(s)
- Matthew F Higgins
- a Department of Life Sciences, Sport, Outdoor and Exercise Science, Derby University, Kedleston Road, Derby DE22 1GB, UK
| | - Susie Wilson
- b Department of Applied Sciences and Health, Coventry University, James Starley Building, Cox Street, Coventry CV1 5FB, UK
| | - Cameron Hill
- b Department of Applied Sciences and Health, Coventry University, James Starley Building, Cox Street, Coventry CV1 5FB, UK
| | - Mike J Price
- b Department of Applied Sciences and Health, Coventry University, James Starley Building, Cox Street, Coventry CV1 5FB, UK
| | - Mike Duncan
- b Department of Applied Sciences and Health, Coventry University, James Starley Building, Cox Street, Coventry CV1 5FB, UK
| | - Jason Tallis
- b Department of Applied Sciences and Health, Coventry University, James Starley Building, Cox Street, Coventry CV1 5FB, UK
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Siegler JC, Marshall P. The effect of metabolic alkalosis on central and peripheral mechanisms associated with exercise-induced muscle fatigue in humans. Exp Physiol 2016; 100:519-30. [PMID: 25727892 DOI: 10.1113/ep085054] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2015] [Accepted: 02/16/2015] [Indexed: 01/23/2023]
Abstract
NEW FINDINGS What is the central question of this study? Does metabolic alkalosis affect central and peripheral mechanisms associated with exercise-induced muscle fatigue in humans? What is the main finding and its importance? Inducing metabolic alkalosis before exercise preserved voluntary activation, but not muscle excitation, after a 2 min maximal voluntary contraction (MVC) followed by ischaemia. An effect of pH was also observed in maximal rates of torque development, where alkalosis mitigated the reduction in maximal rates of torque development after the initial 2 min MVC. For the first time, these results demonstrate a differential effect of pH on voluntary activation as well as maximal rates of torque development after sustained, maximal voluntary knee extension in humans. The increased concentration of protons during fatiguing exercise may contribute to increased activation of group III and IV afferents and subsequently reduced central drive, but this has yet to be confirmed in exercising humans. Here, we determined whether inducing metabolic alkalosis differentially affects descending central drive after fatiguing exercise and whether this effect may, in part, be explained by attenuating group III and IV afferent firing. Eleven men performed a maximal 2 min voluntary knee extension (MVC) followed by a 2 min rest and subsequent 1 min MVC with an occlusive cuff either in placebo [PLA; 0.3 g (kg body weight)(-1) calcium carbonate] or alkalosis conditions [ALK; 0.3 g (kg body weight)(-1) sodium bicarbonate]. Femoral nerve stimulation was applied before exercise, after the 2 min MVC and at 40-60 s intervals throughout the remainder of the protocol to explore central and peripheral mechanisms associated with reductions in maximal force and rate of torque development. Although voluntary activation declined to a similar extent after the 2 min MVC, during the ischaemic period voluntary activation was higher during ALK (PLA, 57 ± 8%; ALK, 76 ± 5%). Maximal voluntary torque declined at similar rates during the task (203 ± 19 N m), but maximal rate of torque development was significantly higher in the ALK conditions after the 2 min MVC (mean difference of 177 ± 60 N m s(-1) ). These results demonstrate the effect of pH on voluntary activation as well as maximal rates of torque development after sustained, maximal voluntary knee extension in humans.
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Affiliation(s)
- Jason C Siegler
- Sport and Exercise Science, School of Science and Health, University of Western Sydney, Sydney, NSW, Australia
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9
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The effect of pH on fatigue during submaximal isometric contractions of the human calf muscle. Eur J Appl Physiol 2014; 115:565-77. [DOI: 10.1007/s00421-014-3027-2] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2014] [Accepted: 10/15/2014] [Indexed: 01/03/2023]
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10
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Flinn S, Herbert K, Graham K, Siegler JC. Differential Effect of Metabolic Alkalosis and Hypoxia on High-Intensity Cycling Performance. J Strength Cond Res 2014; 28:2852-8. [DOI: 10.1519/jsc.0000000000000489] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
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Tallis J, James RS, Little AG, Cox VM, Duncan MJ, Seebacher F. Early effects of ageing on the mechanical performance of isolated locomotory (EDL) and respiratory (diaphragm) skeletal muscle using the work-loop technique. Am J Physiol Regul Integr Comp Physiol 2014; 307:R670-84. [PMID: 24990861 DOI: 10.1152/ajpregu.00115.2014] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Previous isolated muscle studies examining the effects of ageing on contractility have used isometric protocols, which have been shown to have poor relevance to dynamic muscle performance in vivo. The present study uniquely uses the work-loop technique for a more realistic estimation of in vivo muscle function to examine changes in mammalian skeletal muscle mechanical properties with age. Measurements of maximal isometric stress, activation and relaxation time, maximal power output, and sustained power output during repetitive activation and recovery are compared in locomotory extensor digitorum longus (EDL) and core diaphragm muscle isolated from 3-, 10-, 30-, and 50-wk-old female mice to examine the early onset of ageing. A progressive age-related reduction in maximal isometric stress that was of greater magnitude than the decrease in maximal power output occurred in both muscles. Maximal force and power developed earlier in diaphragm than EDL muscle but demonstrated a greater age-related decline. The present study indicates that ability to sustain skeletal muscle power output through repetitive contraction is age- and muscle-dependent, which may help rationalize previously reported equivocal results from examination of the effect of age on muscular endurance. The age-related decline in EDL muscle performance is prevalent without a significant reduction in muscle mass, and biochemical analysis of key marker enzymes suggests that although there is some evidence of a more oxidative fiber type, this is not the primary contributor to the early age-related reduction in muscle contractility.
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Affiliation(s)
- Jason Tallis
- Department of Biomolecular and Sport Sciences, Coventry, United Kingdom; and
| | - Rob S James
- Department of Biomolecular and Sport Sciences, Coventry, United Kingdom; and
| | - Alexander G Little
- School of Biological Sciences, University of Sydney, Sydney, New South Wales, Australia
| | - Val M Cox
- Department of Biomolecular and Sport Sciences, Coventry, United Kingdom; and
| | - Michael J Duncan
- Department of Biomolecular and Sport Sciences, Coventry, United Kingdom; and
| | - Frank Seebacher
- School of Biological Sciences, University of Sydney, Sydney, New South Wales, Australia
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Siegler JC, Marshall PWM, Raftry S, Brooks C, Dowswell B, Romero R, Green S. The differential effect of metabolic alkalosis on maximum force and rate of force development during repeated, high-intensity cycling. J Appl Physiol (1985) 2013; 115:1634-40. [DOI: 10.1152/japplphysiol.00688.2013] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The purpose of this investigation was to assess the influence of sodium bicarbonate supplementation on maximal force production, rate of force development (RFD), and muscle recruitment during repeated bouts of high-intensity cycling. Ten male and female ( n = 10) subjects completed two fixed-cadence, high-intensity cycling trials. Each trial consisted of a series of 30-s efforts at 120% peak power output (maximum graded test) that were interspersed with 30-s recovery periods until task failure. Prior to each trial, subjects consumed 0.3 g/kg sodium bicarbonate (ALK) or placebo (PLA). Maximal voluntary contractions were performed immediately after each 30-s effort. Maximal force (Fmax) was calculated as the greatest force recorded over a 25-ms period throughout the entire contraction duration while maximal RFD (RFDmax) was calculated as the greatest 10-ms average slope throughout that same contraction. Fmax declined similarly in both the ALK and PLA conditions, with baseline values (ALK: 1,226 ± 393 N; PLA: 1,222 ± 369 N) declining nearly 295 ± 54 N [95% confidence interval (CI) = 84–508 N; P < 0.006]. RFDmax also declined in both trials; however, a differential effect persisted between the ALK and PLA conditions. A main effect of condition was observed across the performance time period, with RFDmax on average higher during ALK (ALK: 8,729 ± 1,169 N/s; PLA: 7,691 ± 1,526 N/s; mean difference between conditions 1,038 ± 451 N/s, 95% CI = 17–2,059 N/s; P < 0.048). These results demonstrate a differential effect of alkalosis on maximum force vs. maximum rate of force development during a whole body fatiguing task.
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Affiliation(s)
| | | | - Sean Raftry
- Sport and Exercise Science, School of Science and Health, and
| | - Cristy Brooks
- Sport and Exercise Science, School of Science and Health, and
| | - Ben Dowswell
- Sport and Exercise Science, School of Science and Health, and
| | - Rick Romero
- Sport and Exercise Science, School of Science and Health, and
| | - Simon Green
- Sport and Exercise Science, School of Science and Health, and
- School of Medicine, University of Western Sydney Campbelltown Campus, Sydney, Australia
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