Modeling the depletion and reconstitution of W': Effects of prior exercise on cycling tolerance

Respir Physiol Neurobiol. 2021 Mar:285:103590. doi: 10.1016/j.resp.2020.103590. Epub 2020 Nov 30.

Abstract

Thirteen healthy male subjects (age 28 ± 7 years) performed tests for critical power and W' determination and two square-wave high-intensity exercises until exhaustion either with prior very-heavy intensity cycling (EXP) or without (CON). Prior exercise bout induced a depletion of 60 % of W'. After 10 min of recovery, W' reconstitution was not fully achieved (∼ 92 %). Time to exhaustion and Δ blood lactate concentration were significantly lower in EXP compared to CON (595 ± 118 s vs. 683 ± 148 s; 3.5 ± 1.2 mmol.L-1 vs. 8.8 ± 2.3 mmol.L-1; p < 0.05, respectively). Oxygen uptake (VO2) and heart rate were significantly higher in EXP, during the first 150 s of exercise (p < 0.05). The carbon dioxide production kinetics was significantly slower in EXP (mean response time = 87.8 ± 17.8 s vs. 73.7 ± 16.6 s in CON; p < 0.05). Thus, prior exercise impairs high-intensity cycling performance which can partly be explained by physiological disturbances linked to W' depletion.

Keywords: Cycling tolerance; Exhaustion; VO(2) dynamic; Very-heavy intensity domain; W’ balance; W′ reconstitution.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Bicycling / physiology*
  • Carbon Dioxide / metabolism
  • Exercise / physiology*
  • Exercise Tolerance / physiology*
  • Heart Rate / physiology
  • Humans
  • Lactic Acid / blood
  • Male
  • Oxygen Consumption / physiology*
  • Young Adult

Substances

  • Carbon Dioxide
  • Lactic Acid