In our study, analysis of concentric, eccentric, and mean contraction torques of the knee extensors revealed important differences between the age groups, ie, older men showed lower concentric, eccentric, and mean contraction torques than young men.
The main results demonstrated that concentric, eccentric, and mean contraction torques for knee extensors were significantly (P < 0.05) higher for younger men than for elderly men.
Analyzing the muscle strength data (ie, concentric, isometric, eccentric, and mean contraction torques), it was found that younger and older men showed similar elbow flexor strength.
20 The maximum contraction torque for four concentric contractions was used for further analysis.
The maximum isometric contraction torque of three attempts was used for further analysis.
Maximum eccentric contraction torque developed at the set was used for further analysis.
However, MVC and electrically induced muscle contraction torque did not differ between phases (P < 0.05, Table 1).
To quantify maximum concentric contraction torque, the volunteers performed a set of four maximum concentric contractions at 60° per second for the elbow flexors and the knee extensors.
Maximal voluntary contraction torque, voluntary activation (twitch interpolation) and peak twitch torque decreased from pre- to post-exercise (−9 ± 1, −4 ± 1 and −6 ± 1 % all trials compounded, respectively; P < 0.05), with no effect of the temperature or altitude.
When a few seconds into the contraction torque had leveled off, maximal triplet stimulation, manually triggered by one of the investigators, was superimposed upon the MVC.
