The purpose of this study was 3-fold: (a) to determine if the mathematical model used to estimate the electromyographic fatigue threshold (EMG FT) and physical working capacity at the heart rate threshold (PWCHRT) could be applied to V̇O2 measurements, (b) to propose a new fatigue threshold called the physical working capacity at the oxygen consumption threshold (PWCV̇O2), and (c) to compare the power output at the PWCV̇O2 to those of the EMGFT, PWCHRT, and ventilatory threshold (VT). Fifteen adult volunteers (mean age ± SD = 22 ± 2 years) performed a maximal cycle ergometer test to determine V̇O2peak and VT as well as 4 8-minute submaximal work bouts for the determination of PWCHRT, EMG FT, and PWCV̇O2- A 1-way repeated measures analysis of variance (ANOVA) with Tukey post hoc comparison indicated that PWC HRT (84 ± 36) was significantly (p < 0.05) less than EMGFT (126 ± 51), but there were no differences for PWC V̇O2 (111 ± 44) and VT (111 ± 60) versus PWC HRT or EMGFT. The results of this study indicated that (a) the mathematical model used to determine the PWCHRT and EMG FT was applicable to the measurement of V̇O2 and could be used to estimate the PWCV̇O2 during cycle ergometry, (b) there was a difference in the mean power outputs that corresponded to the fatigue thresholds determined from EMG and heart rate measurements, and (c) the PWCV̇O2 test may provide a useful submaximal technique for estimating the VT.
- Fatigue thresholds
- V̇O slow component
ASJC Scopus subject areas
- Orthopedics and Sports Medicine
- Physical Therapy, Sports Therapy and Rehabilitation