Fast-start strategy increases the time spent above 95 %VO2max during severe-intensity intermittent running exercise.
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.
Human Performance Research Group, Center for Health and Exercise Science, CEFID, UDESC, Rua Pascoal Simone, 358 Coqueiros, Florianopolis, SC CEP 88080-350, Brazil.
Rafael Alves
RA
de Aguiar
Tiago
T
Turnes
Rogério Santos
RS
de Oliveira Cruz
Fabrizio
F
Caputo
D000328:Adult; D000704:Analysis of Variance; D015415:Biomarkers / Q000097:blood; D015444:Exercise; D005080:Exercise Test; D017079:Exercise Tolerance; D006339:Heart Rate; D006801:Humans; D019344:Lactic Acid / Q000097:blood; D016014:Linear Models; D008297:Male; D009119:Muscle Contraction; D018763:Muscle Fatigue; D018482:Muscle, Skeletal / Q000378:metabolism / Q000502:physiology*; D010101:Oxygen Consumption; D012420:Running; D013997:Time Factors; D055815:Young Adult
D015415:Biomarkers; D019344:Lactic Acid