Repeated Bout Effect Was More Expressed in Young Adult Males Than in Elderly Males and Boys

Figure 2

Voluntary (MVC (a) maximal voluntary contraction force of quadriceps muscle; H of DJs (f) height of drop jumps; VA (e) quadriceps muscle voluntary activation index) and electrically (P20 (b) and P100 (c) muscle contraction force evoked by stimulating quadriceps muscle at 20 Hz and 100 Hz frequencies, resp.; P20/P100 (d) ratio of P20/P100 indicates the level of low frequency fatigue) induced muscle performance after bout 1 and bout 2 in boys (𝑛=11), young adult males (𝑛=11), and elderly males (𝑛=11) (mean ± SD). ^*,**𝑃<0.05 and 𝑃<0.001, compared with the before-exercise level; ^#𝑃<0.05, compared with bout 1.

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