A Mechanomyographic Fatigue Threshold Test for Cycling

作者：Zuniga J M^*; Housh T J; Camic C L; Hendrix C R; Schmidt R J; Mielke M; Johnson G O

来源：International Journal of Sports Medicine, 2010, 31(9): 636-643.

DOI：10.1055/s-0030-1255112

• pedaling exercise
• mechanomyography
• frequency-based test
• exercise intensity domains

The purposes of this study were twofold: 1) to derive the mechanomyographic mean power frequency fatigue threshold (MMG MPFFT) for submaximal cycle ergometry; and 2) to compare the power outputs associated to the MMG MPFFT to other neuromuscular and gas exchange fatigue thresholds. 9 adults (5 men and 4 women; mean +/- SD age = 23.7 +/- 3.7 years; body weight = 66.3 +/- 8.2 kg) performed an incremental cycle ergometry test to exhaustion while expired gas samples, electromyographic (EMG), and MMG signals were measured from the vastus lateralis muscle. The non-significant correlations (r = 0.17 to 0.66; p > 0.05) among the physical working capacity at the fatigue threshold (PWCFT), MMG MPFFT, and gas exchange threshold (GET) suggested that different physiological mechanisms may underlie these 3 fatigue thresholds. A significant correlation (r = 0.83) for the MPFFT vs. respiratory compensation point (RCP) suggested that these fatigue thresholds may be mediated by a common physiological mechanism. In addition, the significantly lower mean values found for the PWCFT (mean +/- SD = 163 +/- 43 W), MMG MPFFT (132 +/- 33 W), and GET (144 +/- 28 W) than MPFFT (196 +/- 53 W) and RCP (202 +/- 41 W) suggested that these gas exchange and neuromuscular fatigue thresholds may demarcate different exercise intensity domains.

• 出版日期2010-9