Fig. 4.
The percent change in peak force (a) and force time integrals (b) between the first and the last fatiguing trains during the three fatigue protocols. Note the positive percentage change in peak force for the frequency-modulation protocol (a) and the positive percentage change in force time integral for frequency-modulation and PD-modulation protocols (b). *Significant differences between protocols (p ≤ 0.01).