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Bourdas DI, Souglis A, Zacharakis ED, Geladas ND, Travlos AK. Meta-Analysis of Carbohydrate Solution Intake during Prolonged Exercise in Adults: From the Last 45+ Years' Perspective. Nutrients 2021; 13:4223. [PMID: 34959776 PMCID: PMC8704222 DOI: 10.3390/nu13124223] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2021] [Revised: 11/02/2021] [Accepted: 11/22/2021] [Indexed: 12/17/2022] Open
Abstract
Carbohydrate (CHO) supplementation during prolonged exercise postpones fatigue. However, the optimum administration timing, dosage, type of CHO intake, and possible interaction of the ergogenic effect with athletes' cardiorespiratory fitness (CRF) are not clear. Ninety-six studies (from relevant databases based on predefined eligibility criteria) were selected for meta-analysis to investigate the acute effect of ≤20% CHO solutions on prolonged exercise performance. The between-subject standardized mean difference [SMD = ([mean post-value treatment group-mean post-value control group]/pooled variance)] was assessed. Overall, SMD [95% CI] of 0.43 [0.35, 0.51] was significant (p < 0.001). Subgroup analysis showed that SMD was reduced as the subjects' CRF level increased, with a 6-8% CHO solution composed of GL:FRU improving performance (exercise: 1-4 h); administration during the event led to a superior performance compared to administration before the exercise, with a 6-8% single-source CHO solution increasing performance in intermittent and 'stop and start' sports and an ~6% CHO solution appearing beneficial for 45-60 min exercises, but there were no significant differences between subjects' gender and age groups, varied CHO concentrations, doses, or types in the effect measurement. The evidence found was sound enough to support the hypothesis that CHO solutions, when ingested during endurance exercise, have ergogenic action and a possible crossover interaction with the subject's CRF.
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Affiliation(s)
- Dimitrios I. Bourdas
- Section of Sport Medicine & Biology of Exercise, School of Physical Education and Sports Science, National and Kapodistrian University of Athens, 41 Ethnikis Antistasis, 17237 Athens, Greece;
| | - Athanasios Souglis
- Section of Didactics and Coaching in Sport Games, School of Physical Education & Sport Science, National and Kapodistrian University of Athens, 41 Ethnikis Antistasis, 17237 Athens, Greece; (A.S.); (E.D.Z.)
| | - Emmanouil D. Zacharakis
- Section of Didactics and Coaching in Sport Games, School of Physical Education & Sport Science, National and Kapodistrian University of Athens, 41 Ethnikis Antistasis, 17237 Athens, Greece; (A.S.); (E.D.Z.)
| | - Nickos D. Geladas
- Section of Sport Medicine & Biology of Exercise, School of Physical Education and Sports Science, National and Kapodistrian University of Athens, 41 Ethnikis Antistasis, 17237 Athens, Greece;
| | - Antonios K. Travlos
- Department of Sports Organization and Management, Faculty of Human Movement and Quality of Life Sciences, University of Peloponnese, Efstathiou and Stamatikis Valioti & Plataion Avenue, 23100 Tripoli, Greece;
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The Mediterranean dietary pattern for optimising health and performance in competitive athletes: a narrative review. Br J Nutr 2021; 128:1285-1298. [PMID: 34420536 DOI: 10.1017/s0007114521003202] [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: 11/06/2022]
Abstract
Nutrition plays a key role in training for, and competing in, competitive sport, and is essential for reducing risk of injury and illness, recovering and adapting between bouts of activity, and enhancing performance. Consumption of a Mediterranean diet (MedDiet) has been demonstrated to reduce risk of various non-communicable diseases and increase longevity. Following the key principles of a MedDiet could also represent a useful framework for good nutrition in competitive athletes under most circumstances, with potential benefits for health and performance parameters. In this review, we discuss the potential effects of a MedDiet, or individual foods and compounds readily available in this dietary pattern, on oxidative stress and inflammation, injury and illness risk, vascular and cognitive function, and exercise performance in competitive athletes. We also highlight potential modifications which could be made to the MedDiet (whilst otherwise adhering to the key principles of this dietary pattern) in accordance with contemporary sports nutrition practices, to maximise health and performance effects. In addition, we discuss potential directions for future research.
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Learsi SK, Ghiarone T, Silva-Cavalcante MD, Andrade-Souza VA, Ataide-Silva T, Bertuzzi R, de Araujo GG, McConell G, Lima-Silva AE. Cycling time trial performance is improved by carbohydrate ingestion during exercise regardless of a fed or fasted state. Scand J Med Sci Sports 2019; 29:651-662. [PMID: 30672619 DOI: 10.1111/sms.13393] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2018] [Revised: 01/14/2019] [Accepted: 01/16/2019] [Indexed: 11/29/2022]
Abstract
PURPOSE We tested the hypothesis that carbohydrate ingestion during exercise improves time trial (TT) performance and that this carbohydrate-induced improvement is greater when carbohydrates are ingested during exercise in a fasted rather than a fed state. METHODS Nine males performed 105 minutes of constant-load exercise (50% of the difference between the first and second lactate thresholds), followed by a 10-km cycling TT. Exercise started at 9 am, 3 hours after either breakfast (FED, 824 kcal, 67% carbohydrate) or a 15-hour overnight fast (FAST). Before exercise, after every 15 minutes of exercise and at 5 km of the TT, participants ingested 2 mL kg-1 body mass of a non-caloric sweetened solution containing either carbohydrate (8% of maltodextrin, CHO) or placebo (0% carbohydrate, PLA). RESULTS Irrespective of the fasting state, when carbohydrate was ingested during exercise, the rating of perceived exertion (RPE) was lower throughout the constant-load exercise, while the plasma glucose concentration and carbohydrate oxidation were higher during the last stages of the constant-load exercise (P < 0.05). Consequently, TT performance was faster when carbohydrate was ingested during exercise (18.5 ± 0.3 and 18.7 ± 0.4 minutes for the FEDCHO and FASTCHO conditions, respectively) than when the placebo was ingested during exercise (20.2 ± 0.8 and 21.7 ± 1.4 minutes for the FEDPLA and FASTPLA conditions, respectively), regardless of fasting. CONCLUSION These findings indicate that even when breakfast is provided before exercise, carbohydrate ingestion during exercise is still beneficial for exercise performance. However, ingesting carbohydrate during exercise can overcome a lack of breakfast.
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Affiliation(s)
- Sara K Learsi
- Sport Science Research Group, Academic Center of Vitoria, Federal University of Pernambuco, Vitoria de Santo Antao, Brazil.,Department of Physical Education, Sciences Applied Sciences in Sports Research Group, Federal University of Alagoas, Maceio, Brazil
| | - Thaysa Ghiarone
- Sport Science Research Group, Academic Center of Vitoria, Federal University of Pernambuco, Vitoria de Santo Antao, Brazil
| | - Marcos D Silva-Cavalcante
- Sport Science Research Group, Academic Center of Vitoria, Federal University of Pernambuco, Vitoria de Santo Antao, Brazil
| | - Victor A Andrade-Souza
- Sport Science Research Group, Academic Center of Vitoria, Federal University of Pernambuco, Vitoria de Santo Antao, Brazil
| | - Thays Ataide-Silva
- Sport Science Research Group, Academic Center of Vitoria, Federal University of Pernambuco, Vitoria de Santo Antao, Brazil
| | - Romulo Bertuzzi
- Endurance Performance Research Group, School of Physical Education and Sport, University of São Paulo, São Paulo, Brazil
| | - Gustavo G de Araujo
- Department of Physical Education, Sciences Applied Sciences in Sports Research Group, Federal University of Alagoas, Maceio, Brazil
| | - Glenn McConell
- Institute for Health and Sport, Victoria University, Footscray, Victoria, Australia
| | - Adriano E Lima-Silva
- Sport Science Research Group, Academic Center of Vitoria, Federal University of Pernambuco, Vitoria de Santo Antao, Brazil.,Human Performance Research Group, Academic Department of Physical Education, Technological Federal University of Parana, Curitiba, Brazil
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McCartney D, Desbrow B, Irwin C. Post-exercise Ingestion of Carbohydrate, Protein and Water: A Systematic Review and Meta-analysis for Effects on Subsequent Athletic Performance. Sports Med 2018; 48:379-408. [PMID: 29098657 DOI: 10.1007/s40279-017-0800-5] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
BACKGROUND Athletes may complete consecutive exercise sessions with limited recovery time between bouts (e.g. ≤ 4 h). Nutritional strategies that optimise post-exercise recovery in these situations are therefore important. OBJECTIVE This two-part review investigated the effect of consuming carbohydrate (CHO) and protein with water (W) following exercise on subsequent athletic (endurance/anaerobic exercise) performance. DATA SOURCES Studies were identified by searching the online databases SPORTDiscus, PubMed, Web of Science and Scopus. STUDY ELIGIBILITY CRITERIA AND INTERVENTIONS Investigations that measured endurance performance (≥ 5 min duration) ≤ 4 h after a standardised exercise bout (any type) under the following control vs. intervention conditions were included: Part 1: W vs. CHO ingested with an equal volume of W (CHO + W); and, Part 2: CHO + W vs. protein (PRO) ingested with CHO and an equal volume of W (PRO + CHO + W), where CHO or energy intake was matched. STUDY APPRAISAL AND SYNTHESIS METHODS Publications were examined for bias using the Rosendal scale. Random-effects meta-analyses and meta-regression analyses were conducted to evaluate intervention efficacy. RESULTS The quality assessment yielded a Rosendal score of 63 ± 9% (mean ± standard deviation). Part 1: 45 trials (n = 486) were reviewed. Ingesting CHO + W (102 ± 50 g CHO; 0.8 ± 0.6 g CHO kg-1 h-1) improved exercise performance compared with W (1.6 ± 0.7 L); %Δ mean power output = 4.0, 95% confidence interval 3.2-4.7 (I 2 = 43.9). Improvement was attenuated when participants were 'Fed' (a meal 2-4 h prior to the initial bout) as opposed to 'Fasted' (p = 0.012). Part 2: 13 trials (n = 125) were reviewed. Ingesting PRO + CHO + W (35 ± 26 g PRO; 0.5 ± 0.4 g PRO kg-1) did not affect exercise performance compared with CHO + W (115 ± 61 g CHO; 0.6 ± 0.3 g CHO·kg body mass-1 h-1; 1.2 ± 0.6 L); %Δ mean power output = 0.5, 95% confidence interval - 0.5 to 1.6 (I 2 = 72.9). CONCLUSIONS Athletes with limited time for recovery between consecutive exercise sessions should prioritise CHO and fluid ingestion to enhance subsequent athletic performance. PROSPERO REGISTRATION NUMBER: CRD42016046807.
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Affiliation(s)
- Danielle McCartney
- School of Allied Health Sciences and Menzies Health Institute Queensland, Griffith University, Gold Coast, Parklands Drive, Southport, QLD, 4222, Australia.
| | - Ben Desbrow
- School of Allied Health Sciences and Menzies Health Institute Queensland, Griffith University, Gold Coast, Parklands Drive, Southport, QLD, 4222, Australia
| | - Christopher Irwin
- School of Allied Health Sciences and Menzies Health Institute Queensland, Griffith University, Gold Coast, Parklands Drive, Southport, QLD, 4222, Australia
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Finger D, Lanferdini FJ, Farinha JB, Brusco CM, Helal L, Boeno FP, Cadore EL, Pinto RS. Ingestion of carbohydrate or carbohydrate plus protein does not enhance performance during endurance exercise: a randomized crossover placebo-controlled clinical trial. Appl Physiol Nutr Metab 2018; 43:937-944. [PMID: 29544062 DOI: 10.1139/apnm-2017-0835] [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] [Indexed: 11/22/2022]
Abstract
A beverage containing protein (PRO) and carbohydrate (CHO) may have an ergogenic effect on endurance performance. However, evidence regarding its efficacy on similar conditions to athletes' race day is still lacking. The objective of this study was to compare the effects of 3 different nutritional supplementation strategies on performance and muscle recovery in a duathlon protocol. Thirteen male athletes (29.7 ± 7.7 years) participated in 3 simulated Olympic-distance duathlon trials (SDTs) under 3 different, randomly assigned supplementation regimens: CHO drink (75 g CHO), isocaloric CHO plus PRO drink (60.5 g CHO and 14.5 g PRO), and placebo drink (PLA). Supplements were offered during the cycling bout. Blood samples were collected before, immediately after, and 24 h after each SDT for creatine kinase (CK) analysis. Isometric peak torque (PT) was measured before and 24 h after each SDT. The primary outcome measure was the time to complete the 5-km running section (t5km) at a self-selected pace. There was no difference in t5km between CHO (1270.3 ± 130.5 s), CHO+PRO (1267.2 ± 138.9 s), and PLA (1275.4 ± 120 s); p = 0.87, effect size (ES) ≤ 0.1. Pre-post changes for PT and CK were not significant for any of the 3 conditions (PT: p = 0.24, ES ≤ 0.4; CK: p = 0.32, ES = 0.3-1.04). For endurance sports lasting up to 2 h, with a pre-exercise meal containing CHO at 1.5 g·kg-1, supplementation with CHO or CHO+PRO does not offer additional benefits for performance and muscle recovery when compared with PLA.
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Affiliation(s)
- Débora Finger
- a Exercise Research Laboratory, School of Physical Education, Physiotherapy and Dance, Universidade Federal do Rio Grande do Sul, Rua Felizardo, 750, Jardim Botânico, CEP: 90690-200, Porto Alegre, RS, Brazil
| | - Fábio Juner Lanferdini
- a Exercise Research Laboratory, School of Physical Education, Physiotherapy and Dance, Universidade Federal do Rio Grande do Sul, Rua Felizardo, 750, Jardim Botânico, CEP: 90690-200, Porto Alegre, RS, Brazil.,b Physical Education Course, Universidade Regional Integrada do Alto Uruguai e das Missões, Av. Universidade das Missões, 464 - Universitário, CEP: 98802-470, Santo Ângelo, RS, Brazil
| | - Juliano Boufleur Farinha
- a Exercise Research Laboratory, School of Physical Education, Physiotherapy and Dance, Universidade Federal do Rio Grande do Sul, Rua Felizardo, 750, Jardim Botânico, CEP: 90690-200, Porto Alegre, RS, Brazil
| | - Clarissa Müller Brusco
- a Exercise Research Laboratory, School of Physical Education, Physiotherapy and Dance, Universidade Federal do Rio Grande do Sul, Rua Felizardo, 750, Jardim Botânico, CEP: 90690-200, Porto Alegre, RS, Brazil
| | - Lucas Helal
- c Exercise Pathophysiology Laboratory, School of Medicine, Graduate Program in Cardiology and Cardiovascular Sciences, Hospital de Clinicas de Porto Alegre, Universidade Federal do Rio Grande do Sul, Rua Ramiro Barcelos 2350, Largo Eduardo Zaccaro Faraco, CEP: 90035-903, Porto Alegre, RS, Brazil
| | - Francesco Pinto Boeno
- a Exercise Research Laboratory, School of Physical Education, Physiotherapy and Dance, Universidade Federal do Rio Grande do Sul, Rua Felizardo, 750, Jardim Botânico, CEP: 90690-200, Porto Alegre, RS, Brazil
| | - Eduardo Lusa Cadore
- a Exercise Research Laboratory, School of Physical Education, Physiotherapy and Dance, Universidade Federal do Rio Grande do Sul, Rua Felizardo, 750, Jardim Botânico, CEP: 90690-200, Porto Alegre, RS, Brazil
| | - Ronei Silveira Pinto
- a Exercise Research Laboratory, School of Physical Education, Physiotherapy and Dance, Universidade Federal do Rio Grande do Sul, Rua Felizardo, 750, Jardim Botânico, CEP: 90690-200, Porto Alegre, RS, Brazil
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Taylor D, Smith MF. The Influence of Mid-Event Deception on Psychophysiological Status and Pacing Can Persist across Consecutive Disciplines and Enhance Self-paced Multi-modal Endurance Performance. Front Physiol 2017; 8:6. [PMID: 28174540 PMCID: PMC5258730 DOI: 10.3389/fphys.2017.00006] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2016] [Accepted: 01/04/2017] [Indexed: 02/03/2023] Open
Abstract
Purpose: To examine the effects of deceptively aggressive bike pacing on performance, pacing, and associated physiological and perceptual responses during simulated sprint-distance triathlon. Methods: Ten non-elite, competitive male triathletes completed three simulated sprint-distance triathlons (0.75 km swim, 500 kJ bike, 5 km run), the first of which established personal best “baseline” performance (BL). During the remaining two trials athletes maintained a cycling power output 5% greater than BL, before completing the run as quickly as possible. However, participants were informed of this aggressive cycling strategy before and during only one of the two trials (HON). Prior to the alternate trial (DEC), participants were misinformed that cycling power output would equal that of BL, with on-screen feedback manipulated to reinforce this deception. Results: Compared to BL, a significantly faster run performance was observed following DEC cycling (p < 0.05) but not following HON cycling (1348 ± 140 vs. 1333 ± 129 s and 1350 ± 135 s, for BL, DEC, and HON, respectively). As such, magnitude-based inferences suggest HON running was more likely to be slower, than faster, compared to BL, and that DEC running was probably faster than both BL and HON. Despite a trend for overall triathlon performance to be quicker during DEC (4339 ± 395 s) compared to HON (4356 ± 384 s), the only significant and almost certainly meaningful differences were between each of these trials and BL (4465 ± 420 s; p < 0.05). Generally, physiological and perceptual strain increased with higher cycling intensities, with little, if any, substantial difference in physiological and perceptual response during each triathlon run. Conclusions: The present study is the first to show that mid-event pace deception can have a practically meaningful effect on multi-modal endurance performance, though the relative importance of different psychophysiological and emotional responses remains unclear. Whilst our findings support the view that some form of anticipatory “template” may be used by athletes to interpret levels of psychophysiological and emotional strain, and regulate exercise intensity accordingly, they would also suggest that individual constructs such as RPE and affect may be more loosely tied with pacing than previously suggested.
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Affiliation(s)
- Daniel Taylor
- School of Sport and Exercise Science, University of Lincoln Lincoln, UK
| | - Mark F Smith
- School of Sport and Exercise Science, University of Lincoln Lincoln, UK
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7
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Pöchmüller M, Schwingshackl L, Colombani PC, Hoffmann G. A systematic review and meta-analysis of carbohydrate benefits associated with randomized controlled competition-based performance trials. J Int Soc Sports Nutr 2016; 13:27. [PMID: 27408608 PMCID: PMC4940907 DOI: 10.1186/s12970-016-0139-6] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2016] [Accepted: 06/28/2016] [Indexed: 11/10/2022] Open
Abstract
Background Carbohydrate supplements are widely used by athletes as an ergogenic aid before and during sports events. The present systematic review and meta-analysis aimed at synthesizing all available data from randomized controlled trials performed under real-life conditions. Methods MEDLINE, EMBASE, and the Cochrane Central Register of Controlled Trials were searched systematically up to February 2015. Study groups were categorized according to test mode and type of performance measurement. Subgroup analyses were done with reference to exercise duration and range of carbohydrate concentration. Random effects and fixed effect meta-analyses were performed using the Software package by the Cochrane Collaboration Review Manager 5.3. Results Twenty-four randomized controlled trials met the objectives and were included in the present systematic review, 16 of which provided data for meta-analyses. Carbohydrate supplementations were associated with a significantly shorter exercise time in groups performing submaximal exercise followed by a time trial [mean difference −0.9 min (95 % confidence interval −1.7, −0.2), p = 0.02] as compared to controls. Subgroup analysis showed that improvements were specific for studies administering a concentration of carbohydrates between 6 and 8 % [mean difference −1.0 min (95 % confidence interval −1.9, −0.0), p = 0.04]. Concerning groups with submaximal exercise followed by a time trial measuring power accomplished within a fixed time or distance, mean power output was significantly higher following carbohydrate load (mean difference 20.2 W (95 % confidence interval 9.0, 31.5), p = 0.0004]. Likewise, mean power output was significantly increased following carbohydrate intervention in groups with time trial measuring power within a fixed time or distance (mean difference 8.1 W (95 % confidence interval 0.5, 15.7) p = 0.04]. Conclusion Due to the limitations of this systematic review, results can only be applied to a subset of athletes (trained male cyclists). For those, we could observe a potential ergogenic benefit of carbohydrate supplementation especially in a concentration range between 6 and 8 % when exercising longer than 90 min. Electronic supplementary material The online version of this article (doi:10.1186/s12970-016-0139-6) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Martin Pöchmüller
- Department of Nutritional Sciences, Faculty of Life Sciences, University of Vienna, Althanstraße 14 (UZAII), A-1090 Vienna, Austria
| | - Lukas Schwingshackl
- German Institute of Human Nutrition, Arthur-Scheunert-Allee 114-116, D-14558 Nuthetal, Germany
| | - Paolo C Colombani
- Swiss Federal Institute of Sport Magglingen (SFISM), CH-2532 Magglingen, Switzerland
| | - Georg Hoffmann
- Department of Nutritional Sciences, Faculty of Life Sciences, University of Vienna, Althanstraße 14 (UZAII), A-1090 Vienna, Austria
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Stocks B, Betts JA, McGawley K. Effects of carbohydrate dose and frequency on metabolism, gastrointestinal discomfort, and cross-country skiing performance. Scand J Med Sci Sports 2015; 26:1100-8. [PMID: 26316418 DOI: 10.1111/sms.12544] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/23/2015] [Indexed: 11/29/2022]
Abstract
This study investigated carbohydrate ingestion of varied doses and frequencies during a simulated cross-country skiing time trial. Ten men and three women (age: 30 ± 7 years; V ˙ O 2 m a x : 59.6 ± 5.7 mL/kg/min) completed four, 30-km classic technique roller skiing time trials on a treadmill. A 1:1 maltodextrin-fructose carbohydrate solution was provided at high (2.4 g/min; HC) and moderate (1.2 g/min; MC) ingestion rates, each at high (six feeds; HF) and low (two feeds; LF) frequencies. In the LF trials, blood glucose was elevated following carbohydrate ingestion (at 4 and 19 km) but was reduced at 14 and 29 km compared with HF strategies (P ≤ 0.05). Gastrointestinal discomfort was higher in HC-LF compared with all other trials (P ≤ 0.05). Whole-body lipid oxidation was lower and carbohydrate oxidation was higher in LF compared with HF trials (P ≤ 0.05). While performance time was not significantly different between trials (140:11 ± 15:31, 140:43 ± 17:40, 139:12 ± 15:32 and 140:33 ± 17:46 min:s in HC-HF, HC-LF, MC-HF, and MC-LF, respectively; P > 0.05), it was improved with trial order (P < 0.001). There was no effect of order on any other variable (P > 0.05). Altering carbohydrate dose or frequency does not affect cross-country ski performance. However, low-frequency carbohydrate ingestion resulted in poorer maintenance of euglycemia, reduced lipid oxidation, and increased gastrointestinal discomfort.
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Affiliation(s)
- B Stocks
- Swedish Winter Sports Research Centre, Department of Health Sciences, Mid Sweden University, Östersund, Sweden.,Human Physiology Research Group, Department for Health, University of Bath, Bath, UK
| | - J A Betts
- Human Physiology Research Group, Department for Health, University of Bath, Bath, UK
| | - K McGawley
- Swedish Winter Sports Research Centre, Department of Health Sciences, Mid Sweden University, Östersund, Sweden
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Taylor D, Smith MF. Effects of deceptive running speed on physiology, perceptual responses, and performance during sprint-distance triathlon. Physiol Behav 2014; 133:45-52. [PMID: 24825782 DOI: 10.1016/j.physbeh.2014.05.002] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2013] [Revised: 02/20/2014] [Accepted: 05/02/2014] [Indexed: 10/25/2022]
Abstract
OBJECTIVE This study examined the effects of speed deception on performance, physiological and perceptual responses, and pacing during sprint-distance triathlon running. METHODS Eight competitive triathletes completed three simulated sprint-distance triathlons (0.75 km swim, 20 km bike, 5 km run) in a randomised order, with swimming and cycling sections replicating baseline triathlon performance. During the first 1.66 km of the run participants maintained an imposed speed, completing the remaining 3.33 km as quickly as possible. Although the participants were informed that initially prescribed running speed would reflect baseline performance, this was true during only one trial (Tri-Run100%). As such, other trials were either 3% faster (Tri-Run103%), or 3% slower (Tri-Run97%) than baseline during this initial period. RESULTS Performance during Tri-Run103% (1346±108 s) was likely faster than Tri-Run97% (1371±108 s), and possibly faster than Tri-Run100% (1360±125 s), with these differences likely to be competitively meaningful. The first 1.66 km of Tri-Run103% induced greater physiological strain compared to other conditions, whilst perceptual responses were not significantly different between trials. CONCLUSIONS It appears that even during 'all-out' triathlon running, athletes maintain some form of 'reserve' capacity which can be accessed by deception. This suggests that expectations and beliefs have a practically meaningful effect on pacing and performance during triathlon, although it is apparent that an individual's conscious intentions are secondary to the brains sensitivity to potentially harmful levels of physiological and perceptual strain.
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Affiliation(s)
- Daniel Taylor
- School of Sport and Exercise Science, University of Lincoln, Lincoln LN6 7TS, United Kingdom.
| | - Mark F Smith
- School of Sport and Exercise Science, University of Lincoln, Lincoln LN6 7TS, United Kingdom
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