The Effect of Skinfold on the Assessment of the Mean Power Frequency at the Fatigue Threshold

The purpose of this study was to determine if the amount of subcutaneous tissue over the quadriceps affects the assessment of mean power frequency at the fatigue threshold (MPF(FT)). It was hypothesized that greater skinfold values will result in lower power outputs associated to the MPF(FT). Fourteen adults (Mean ± SD age = 20.7 ± 0.99; body weight = 72.8 ± 12.6 kg) performed an incremental cycle ergometry test to exhaustion while surface electromyographic (EMG) signals were measured from the vastus lateralis. The skinfold thickness of each leg was taken prior to the test, and skinfold thicknesses were separated into a larger and a smaller groups. The independent t-test showed a significant difference (p = 0.01) between the power outputs associated to the MPF(FT) of groups with high (Mean ± SD 130.4 ± 34.5 W) versus low skinfold (212.5 ± 61.2 W) values. The results suggested that higher subcutaneous fat may have affected the assessment of MPF(FT) during cycle ergometry.