Fat adaptation followed by carbohydrate loading compromises high-intensity sprint performance

2006 ◽  
Vol 100 (1) ◽  
pp. 194-202 ◽  
Author(s):  
L. Havemann ◽  
S. J. West ◽  
J. H. Goedecke ◽  
I. A. Macdonald ◽  
A. St Clair Gibson ◽  
...  

The aim of this study was to investigate the effect of a high-fat diet (HFD) followed by 1 day of carbohydrate (CHO) loading on substrate utilization, heart rate variability (HRV), effort perception [rating or perceived exertion (RPE)], muscle recruitment [electromyograph (EMG)], and performance during a 100-km cycling time trial. In this randomized single-blind crossover study, eight well-trained cyclists completed two trials, ingesting either a high-CHO diet (HCD) (68% CHO energy) or an isoenergetic HFD (68% fat energy) for 6 days, followed by 1 day of CHO loading (8–10 g CHO/kg). Subjects completed a 100-km time trial on day 1 and a 1-h cycle at 70% of peak oxygen consumption on days 3, 5, and 7, during which resting HRV and resting and exercising respiratory exchange ratio (RER) were measured. On day 8, subjects completed a 100-km performance time trial, during which blood samples were drawn and EMG was recorded. Ingestion of the HFD reduced RER at rest ( P < 0.005) and during exercise ( P < 0.01) and increased plasma free fatty acid levels ( P < 0.01), indicating increased fat utilization. There was a tendency for the low-frequency power component of HRV to be greater for HFD-CHO ( P = 0.056), suggestive of increased sympathetic activation. Overall 100-km time-trial performance was not different between diets; however, 1-km sprint power output after HFD-CHO was lower ( P < 0.05) compared with HCD-CHO. Despite a reduced power output with HFD-CHO, RPE, heart rate, and EMG were not different between trials. In conclusion, the HFD-CHO dietary strategy increased fat oxidation, but compromised high intensity sprint performance, possibly by increased sympathetic activation or altered contractile function.

2009 ◽  
Vol 19 (4) ◽  
pp. 400-409 ◽  
Author(s):  
Milou Beelen ◽  
Jort Berghuis ◽  
Ben Bonaparte ◽  
Sam B. Ballak ◽  
Asker E. Jeukendrup ◽  
...  

It has been reported previously that mouth rinsing with a carbohydrate-containing solution can improve cycling performance. The purpose of the current study was to investigate the impact of such a carbohydrate mouth rinse on exercise performance during a simulated time trial in a more practical, postprandial setting. Fourteen male endurance-trained athletes were selected to perform 2 exercise tests in the morning after consuming a standardized breakfast. They performed an ~1-hr time trial on a cycle ergometer while rinsing their mouths with either a 6.4% maltodextrin solution (CHO) or water (PLA) after every 12.5% of the set amount of work. Borg’s rating of perceived exertion (RPE) was assessed after every 25% of the set amount of work, and power output and heart rate were recorded continuously throughout the test. Performance time did not differ between treatments and averaged 68.14 ± 1.14 and 67.52 ± 1.00 min in CHO and PLA, respectively (p = .57). In accordance, average power output (265 ± 5 vs. 266 ± 5 W, p = .58), heart rate (169 ± 2 vs. 168 ± 2 beats/min, p = .43), and RPE (16.4 ± 0.3 vs. 16.7 ± 0.3 W, p = .26) did not differ between treatments. Furthermore, after dividing the trial into 8s, no differences in power output, heart rate, or perceived exertion were observed over time between treatments. Carbohydrate mouth rinsing does not improve time-trial performance when exercise is performed in a practical, postprandial setting.


2020 ◽  
Vol 127 (5) ◽  
pp. 912-924 ◽  
Author(s):  
Morgan C. Karow ◽  
Rebecca R. Rogers ◽  
Joseph A. Pederson ◽  
Tyler D. Williams ◽  
Mallory R. Marshall ◽  
...  

This study investigated the effects of preferred and non-preferred warm-up music listening conditions on subsequent exercise performance. A total of 12 physically active male and female participants engaged in a crossover, counterbalanced research design in which they completed exercise trials after 3 different warm-up experiences of (a) no music (NM), (b) preferred music (PREF), and (c) nonpreferred music (NON-PREF). Participants began warming up by rowing at 50% of of age-predicted heart rate maximum (HRmax) for 5 minutes while exposed to the three music conditions. Immediately following the warm-up and cessation of any music, participants completed a 2000-m rowing time trial as fast as possible. Relative power output, trial time, heart rate, rating of perceived exertion, and motivation were analyzed. Results indicated that, compared with NM, relative power output was significantly higher ( p  =   .018), trial time was significantly lower ( p  =   .044), and heart rate was significantly higher ( p  =   .032) during the PREF but not the NON-PREF condition. Rating of perceived exertion was not altered, regardless of music condition ( p > .05). Motivation to exercise was higher during the PREF condition versus the NM ( p  =   .001) and NON-PREF ( p <  .001) conditions. Listening to preferred warm-up music improved subsequent exercise performance compared with no music, while nonpreferred music did not impart ergogenic benefit.


2020 ◽  
Vol 15 (7) ◽  
pp. 964-970
Author(s):  
David Barranco-Gil ◽  
Lidia B. Alejo ◽  
Pedro L. Valenzuela ◽  
Jaime Gil-Cabrera ◽  
Almudena Montalvo-Pérez ◽  
...  

Purpose: To analyze the effects of different warm-up protocols on endurance-cycling performance from an integrative perspective (by assessing perceptual, neuromuscular, physiological, and metabolic variables). Methods: Following a randomized crossover design, 15 male cyclists (35 [9] y; peak oxygen uptake [VO2peak] 66.4 [6.8] mL·kg−1·min−1) performed a 20-minute cycling time trial (TT) preceded by no warm-up, a standard warm-up (10 min at 60% of VO2peak), or a warm-up that was intended to induce potentiation postactivation (PAP warm-up; 5 min at 60% of VO2peak followed by three 10-s all-out sprints). Study outcomes were jumping ability and heart-rate variability (both assessed at baseline and before the TT), TT performance (mean power output), and perceptual (rating of perceived exertion) and physiological (oxygen uptake, muscle oxygenation, heart-rate variability, blood lactate, and thigh skin temperature) responses during and after the TT. Results: Both standard and PAP warm-up (9.7% [4.7%] and 12.9% [6.5%], respectively, P < .001), but not no warm-up (−0.9% [4.8%], P = .074), increased jumping ability and decreased heart-rate variability (−7.9% [14.2%], P = .027; −20.3% [24.7%], P = .006; and −1.7% [10.5%], P = .366). Participants started the TT (minutes 0–3) at a higher power output and oxygen uptake after PAP warm-up compared with the other 2 protocols (P < .05), but no between-conditions differences were found overall for the remainder of outcomes (P > .05). Conclusions: Compared with no warm-up, warming up enhanced jumping performance and sympathetic modulation before the TT, and the inclusion of brief sprints resulted in a higher initial power output during the TT. However, no warm-up benefits were found for overall TT performance or for perceptual or physiological responses during the TT.


2016 ◽  
Vol 11 (8) ◽  
pp. 1024-1028 ◽  
Author(s):  
Sam S.X. Wu ◽  
Jeremiah J. Peiffer ◽  
Peter Peeling ◽  
Jeanick Brisswalter ◽  
Wing Y. Lau ◽  
...  

Purpose:To investigate the effect of 3 swim-pacing profiles on subsequent performance during a sprint-distance triathlon (SDT). Methods:Nine competitive/trained male triathletes completed 5 experimental sessions including a graded running exhaustion test, a 750-m swim time trial (STT), and 3 SDTs. The swim times of the 3 SDTs were matched, but pacing was manipulated to induce positive (ie, speed gradually decreasing from 92% to 73% STT), negative (ie, speed gradually increasing from 73% to 92% STT), or even pacing (constant 82.5% STT). The remaining disciplines were completed at a self-selected maximal pace. Speed over the entire triathlon, power output during the cycle discipline, rating of perceived exertion (RPE) for each discipline, and heart rate during the cycle and run were determined. Results:Faster cycle and overall triathlon times were achieved with positive swim pacing (30.5 ± 1.8 and 65.9 ± 4.0 min, respectively), as compared with the even (31.4 ± 1.0 min, P = .018 and 67.7 ± 3.9 min, P = .034, effect size [ES] = 0.46, respectively) and negative (31.8 ± 1.6 min, P = .011 and 67.3 ± 3.7 min, P = .041, ES = 0.36, respectively) pacing. Positive swim pacing elicited a lower RPE (9 ± 2) than negative swim pacing (11 ± 2, P = .014). No differences were observed in the other measured variables. Conclusions:A positive swim pacing may improve overall SDT performance and should be considered by both elite and age-group athletes during racing.


Sports ◽  
2020 ◽  
Vol 8 (12) ◽  
pp. 156
Author(s):  
Amelia F. Dingley ◽  
Alexander P. Willmott ◽  
John F. T. Fernandes

This study investigated the effectiveness of a self-selected (SS) warm-up on 500 m sprint kayak performance (K500) compared to continuous (CON) and intermittent high intensity (INT)-type warm-ups. Twelve nationally ranked sprint kayakers (age 17.7 ± 2.3 years, mass 69.2 ± 10.8 kg) performed CON (15 min at the power at 2 m·mol−1), INT (10 min at 2 m·mol−1, followed by 5 × 10 s sprints at 200% power at VO2max with 50 s recovery at 55% power at VO2max), and SS (athlete’s normal competition warm-up) warm-ups in a randomised order. After a five-minute passive recovery, K500 performance was determined on a kayak ergometer. Heart rate and blood lactate (BLa) were recorded before and immediately after each warm-up and K500 performance. Ratings of perceived exertion (RPE) were recorded at the end of the warm-up and K500. BLa, heart rate, and RPE were generally higher after the INT than CON and SS warm-ups (p < 0.05). No differences in these parameters were found between the conditions for the time trial (p > 0.05). RPE and changes in BLa and heart rate after the K500 were comparable. There were no differences in K500 performance after the CON, SS, or INT warm-ups. Applied practitioners can, therefore, attain similar performance independent of warm-up type.


2016 ◽  
Vol 11 (6) ◽  
pp. 707-714 ◽  
Author(s):  
Benoit Capostagno ◽  
Michael I. Lambert ◽  
Robert P. Lamberts

Finding the optimal balance between high training loads and recovery is a constant challenge for cyclists and their coaches. Monitoring improvements in performance and levels of fatigue is recommended to correctly adjust training to ensure optimal adaptation. However, many performance tests require a maximal or exhaustive effort, which reduces their real-world application. The purpose of this review was to investigate the development and use of submaximal cycling tests that can be used to predict and monitor cycling performance and training status. Twelve studies met the inclusion criteria, and 3 separate submaximal cycling tests were identified from within those 12. Submaximal variables including gross mechanical efficiency, oxygen uptake (VO2), heart rate, lactate, predicted time to exhaustion (pTE), rating of perceived exertion (RPE), power output, and heart-rate recovery (HRR) were the components of the 3 tests. pTE, submaximal power output, RPE, and HRR appear to have the most value for monitoring improvements in performance and indicate a state of fatigue. This literature review shows that several submaximal cycle tests have been developed over the last decade with the aim to predict, monitor, and optimize cycling performance. To be able to conduct a submaximal test on a regular basis, the test needs to be short in duration and as noninvasive as possible. In addition, a test should capture multiple variables and use multivariate analyses to interpret the submaximal outcomes correctly and alter training prescription if needed.


PeerJ ◽  
2020 ◽  
Vol 8 ◽  
pp. e9791
Author(s):  
Gabriel V. Protzen ◽  
Charles Bartel ◽  
Victor S. Coswig ◽  
Paulo Gentil ◽  
Fabricio B. Del Vecchio

Background One of the most popular high-intensity interval exercises is the called “Tabata Protocol”. However, most investigations have limitations in describing the work intensity, and this fact appears to be due to the protocol unfeasibility. Furthermore, the physiological demands and energetic contribution during this kind of exercise remain unclear. Methods Eight physically active students (21.8 ± 3.7 years) and eight well-trained cycling athletes (27.8 ± 6.4 years) were enrolled. In the first visit, we collected descriptive data and the peak power output (PPO). On the next three visits, in random order, participants performed interval training with the same time structure (effort:rest 20s:10s) but using different intensities (115%, 130%, and 170% of PPO). We collected the number of sprints, power output, oxygen consumption, blood lactate, and heart rate. Results The analysis of variance for multivariate test (number of sprints, power output, blood lactate, peak heart rate and percentage of maximal heart rate) showed significant differences between groups (F = 9.62; p = 0.001) and intensities (F = 384.05; p < 0.001), with no interactions (F = 0.94; p = 0.57). All three energetic contributions and intensities were different between protocols. The higher contribution was aerobic, followed by alactic and lactic. The aerobic contribution was higher at 115%PPO, while the alactic system showed higher contribution at 130%PPO. In conclusion, the aerobic system was predominant in the three exercise protocols, and we observed a higher contribution at lower intensities.


2018 ◽  
Vol 33 (3) ◽  
pp. 428-438 ◽  
Author(s):  
Marguerite Harvey ◽  
Kathryn L Weston ◽  
William K Gray ◽  
Ailish O’Callaghan ◽  
Lloyd L Oates ◽  
...  

Objectives: To investigate whether people with Parkinson’s disease can exercise at a high-intensity across a 12-week intervention and to assess the impact of the intervention on cardiorespiratory fitness. Design: This is a randomized, controlled, feasibility study with waiting list control. Assessors were blinded to group allocation. Setting: The intervention took place at an exercise centre and assessments at a district general hospital. Subjects: This study included 20 people with idiopathic Parkinson’s disease. Intervention: A total of 36 exercise sessions over 12 weeks, with each session lasting ~45 minutes, were conducted. Main measures: The main measures were maximal heart rates achieved during exercise, recruitment rate, attendance, drop-out, change in peak oxygen consumption, cardiac output, cognitive function and quality of life. The study was considered technically feasible if participants achieved ⩾85% of maximal heart rate during exercise. Results: There were 12 male and 8 female participants; they had a mean age of 68.5 years (standard deviation 6.825). Two participants were of Hoehn and Yahr stage I, 11 stage II and 7 stage III. In all, 17 participants completed the intervention. The median (interquartile range) proportion of repetitions delivered across the intervention which met our high-intensity criterion was 80% (67% to 84%). Mean peak heart rate was 88.8% of maximal. Peak oxygen consumption increased by 2.8 mL kg−1 min−1 in the intervention group and 1.5 mL kg−1 min−1 in the control group after 12 weeks of exercise. We estimate that a fully powered randomized controlled trial would require 30 participants per group. Conclusion: High-intensity interval exercise is feasible in people with Parkinson’s disease. Improvements in cardiorespiratory function are promising.


2018 ◽  
Vol 53 (7) ◽  
pp. 426-429 ◽  
Author(s):  
Sebastien Racinais ◽  
Sebastien Moussay ◽  
David Nichols ◽  
Gavin Travers ◽  
Taoufik Belfekih ◽  
...  

ObjectiveTo characterise the core temperature response and power output profile of elite male and female cyclists during the 2016 UCI Road World Championships. This may contribute to formulating environmental heat stress policies.MethodsCore temperature was recorded via an ingestible capsule in 10, 15 and 15 cyclists during the team time trial (TTT), individual time trial (ITT) and road race (RR), respectively. Power output and heart rate were extracted from individual cycling computers. Ambient conditions in direct sunlight were hot (37°C±3°C) but dry (25%±16% relative humidity), corresponding to a wet-bulb globe temperature of 27°C±2°C.ResultsCore temperature increased during all races (p<0.001), reaching higher peak values in TTT (39.8°C±0.9°C) and ITT (39.8°C±0.4°C), relative to RR (39.2°C±0.4°C, p<0.001). The highest temperature recorded was 41.5°C (TTT). Power output was significantly higher during TTT (4.7±0.3 W/kg) and ITT (4.9±0.5 W/kg) than RR (2.7±0.4 W/kg, p<0.001). Heart rate increased during the TTs (p<0.001) while power output decreased (p<0.001).Conclusion85% of the cyclists participating in the study (ie, 34 of 40) reached a core temperature of at least 39°C with 25% (ie, 10 of 40) exceeding 40°C. Higher core temperatures were reached during the time trials than the RR.


2007 ◽  
Vol 2 (2) ◽  
pp. 201-211 ◽  
Author(s):  
Thomas Zochowski ◽  
Elizabeth Johnson ◽  
Gordon G. Sleivert

Context:Warm-up before athletic competition might enhance performance by affecting various physiological parameters. There are few quantitative data available on physiological responses to the warm-up, and the data that have been reported are inconclusive. Similarly, it has been suggested that varying the recovery period after a standardized warm-up might affect subsequent performance.Purpose:To determine the effects of varying post-warm-up recovery time on a subsequent 200-m swimming time trial.Methods:Ten national-caliber swimmers (5 male, 5 female) each swam a 1500-m warm-up and performed a 200-m time trial of their specialty stroke after either 10 or 45 min of passive recovery. Subjects completed 1 time trial in each condition separated by 1 wk in a counterbalanced order. Blood lactate and heart rate were measured immediately after warm-up and 3 min before, immediately after, and 3 min after the time trial. Rating of perceived exertion was measured immediately after the warm-up and time trial.Results:Time-trial performance was significantly improved after 10 min as opposed to 45 min recovery (136.80 ± 20.38 s vs 138.69 ± 20.32 s, P < .05). There were no significant differences between conditions for heart rate and blood lactate after the warm-up. Pre-time-trial heart rate, however, was higher in the 10-min than in the 45-min rest condition (109 ± 14 beats/min vs 94 ± 21 beats/min, P < .05).Conclusions:A post-warm-up recovery time of 10 min rather than 45 min is more beneficial to 200-m swimming time-trial performance.


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