Performance and Fatigue Patterns in Elite Cyclists During 6 h of Simulated Road Racing.

Fatigue resistance is vital for success in elite road cycling, as repeated, intense efforts challenge the athletes' ability to sustain peak performance throughout prolonged races. The present study combined recurrent performance testing and physiological measures during 6 h simulated racing with laboratory testing to investigate factors influencing fatigue resistance. Twelve male national elite cyclists (25 ± 3 years; 76 ± 6 kg and VO2max of 5.2 ± 0.5 L/min) completed incremental power and maximal fat oxidation tests. Subsequently, they underwent field testing with physiological measures and fatigue responses evaluated through peak sprint power and 5 km time trial (TT) testing after 0, 2, 4, and 6 h of exercise. Peak power declined from 1362 ± 176 W in first sprint to 1271 ± 152 W after 2 h (p < 0.01) and then stabilized. In contrast, TT mean power gradually declined from 412 ± 38 W in the first TT to 384 ± 41 W in the final trial, with individual losses ranging from 2% to 14% and moderately correlated (r2 = 0.45) to accumulated exercise time above lactate threshold. High carbohydrate intake (~90 g/h) maintained blood glucose levels, but post-TT [lactate] decreased from 15.1 ± 2 mM to 7.1 ± 2.3 mM, while fat oxidation increased from 0.7 ± 0.3 g/min at 0 h to 1.1 ± 0.1 g/min after 6 h. The study identifies fatigue patterns in national elite cyclists. Peak sprint power stabilized after an initial impairment from 0 to 2 h, while TT power gradually declined over the 6 h simulated race, with increased differentiation in fatigue responses among athletes.

Proposed framework for forecasting heat-effects on motor-cognitive performance in the Summer Olympics.

Heat strain impairs performance across a broad spectrum of sport disciplines. The impeding effects of hyperthermia and dehydration are often ascribed to compromised cardiovascular and muscular functioning, but expert performance also depends on appropriately tuned sensory, motor and cognitive processes. Considering that hyperthermia has implications for central nervous system (CNS) function and fatigue, it is highly relevant to analyze how heat stress forecasted for the upcoming Olympics may influence athletes. This paper proposes and demonstrates the use of a framework combining expected weather conditions with a heat strain and motor-cognitive model to analyze the impact of heat and associated factors on discipline- and scenario-specific performances during the Tokyo 2021 games. We pinpoint that hyperthermia-induced central fatigue may affect prolonged performances and analyze how hyperthermia may impair complex motor-cognitive performance, especially when accompanied by either moderate dehydration or exposure to severe solar radiation. Interestingly, several short explosive performances may benefit from faster cross-bridge contraction velocities at higher muscle temperatures in sport disciplines with little or no negative heat-effect on CNS fatigue or motor-cognitive performance. In the analyses of scenarios and Olympic sport disciplines, we consider thermal impacts on "motor-cognitive factors" such as decision-making, maximal and fine motor-activation as well as the influence on central fatigue and pacing. From this platform, we also provide perspectives on how athletes and coaches can identify risks for their event and potentially mitigate negative motor-cognitive effects for and optimize performance in the environmental settings projected.

Tramadol Does Not Improve Performance or Impair Motor Function in Trained Cyclists.

PURPOSE: To investigate the hypothesis that a therapeutic oral dose of Tramadol improves cycling time trial performance and compromises motor-cognitive performance in highly trained cyclists. METHODS: Following two familiarization trials, 16 highly trained cyclists completed a preloaded time trial (1 h at 60% of peak power followed by a 15-km time trial) after ingestion of 100 mg Tramadol or placebo in a double-blind placebo-controlled counterbalanced crossover design separated by at least 4 d washout. Visuomotor tracking and math tasks were completed during the preload (n = 10) to evaluate effects on cognition and fine motor performance. RESULTS: Time trial mean power output (298 ± 42 W vs 294 ± 44 W) and performance (1474 ± 77 s vs 1483 ± 85 s) were similar with Tramadol and placebo treatment, respectively. In addition, there were no differences in perceived exertion, reported pain, blood pH, lactate, or bicarbonate concentrations across trials. Heart rate was higher (P < 0.001) during the Tramadol time trial (171 ± 8 bpm) compared with placebo (167 ± 9 bpm). None of the combined motor-cognitive tasks were impaired by Tramadol ingestion, in fact fine motor performance was slightly improved (P < 0.05) in the Tramadol trial compared with placebo. CONCLUSIONS: In highly trained cyclists, ingestion of 100 mg Tramadol does not improve performance in a 15-km cycling time trial that was completed after a 1-h preload at 60% peak power. Additionally, a therapeutic dose of Tramadol does not compromise complex motor-cognitive or simple fine motor performances.