Fast-start strategy increases the time spent above 95 %VO2max during severe-intensity intermittent running exercise

Eur J Appl Physiol. 2013 Apr;113(4):941-9. doi: 10.1007/s00421-012-2508-4. Epub 2012 Oct 2.

Abstract

This study aimed to use the intermittent critical velocity (ICV) model to individualize intermittent exercise and analyze whether a fast-start strategy could increase the time spent at or above 95 %VO(2max) (t95VO(2max)) during intermittent exercise. After an incremental test, seven active male subjects performed three intermittent exercise tests until exhaustion at 100, 110, and 120 % of the maximal aerobic velocity to determine ICV. On three occasions, the subjects performed an intermittent exercise test until exhaustion at 105 % (IE105) and 125 % (IE125) of ICV, and at a speed that was initially set at 125 %ICV but which then decreased to 105 %ICV (IE125-105). The intermittent exercise consisted of repeated 30-s runs alternated with 15-s passive rest intervals. There was no difference between the predicted and actual Tlim for IE125 (300 ± 72 s and 284 ± 76 s) and IE105 (1,438 ± 423 s and 1,439 ± 518 s), but for IE125-105 the predicted Tlim underestimated the actual Tlim (888 ± 211 s and 1,051 ± 153 s, respectively). The t95VO(2max) during IE125-105 (289 ± 150 s) was significantly higher than IE125 (113 ± 40 s) and IE105 (106 ± 71 s), but no significant differences were found between IE125 and IE105. It can be concluded that predicting Tlim from the ICV model was affected by the fast-start protocol during intermittent exercise. Furthermore, fast-start protocol was able to increase the time spent at or above 95 %VO2max during intermittent exercise above ICV despite a longer total exercise time at IE105.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Analysis of Variance
  • Biomarkers / blood
  • Exercise Test
  • Exercise Tolerance
  • Exercise*
  • Heart Rate
  • Humans
  • Lactic Acid / blood
  • Linear Models
  • Male
  • Muscle Contraction*
  • Muscle Fatigue
  • Muscle, Skeletal / metabolism
  • Muscle, Skeletal / physiology*
  • Oxygen Consumption*
  • Running*
  • Time Factors
  • Young Adult

Substances

  • Biomarkers
  • Lactic Acid