The influence of occupation and age on maximal and rapid lower extremity strength.

The aims of this study were to 1) examine the influence of age and occupation on maximal and rapid strength of the lower-extremity muscles and 2) examine the relationship between maximal and rapid strength and physical workload (work index (WI)) in the blue-collar (BC) cohort. Peak torque (PT) and peak rate of torque development (peakRTD) of the leg extensors (LE), leg flexors (LF), and plantar flexors (PF) were assessed in 47 young (age = 24.1 ± 2.4 years) and 41 middle-aged (52.4 ± 5.2 years) white-collar (WC) and BC men. Middle-aged workers exhibited lower PT for all muscles, and peakRTD for the LF and PF muscles. A positive relationship (r = 0.59; P < 0.01) was observed between WI and peakRTD for the PF in the young BC workers, however, this relationship was negative (r = -0.45; P = 0.053) for the LF of the middle-aged BC workers. Lowering physical work demands and/or incorporating effective health-related practices for employees may be appealing strategies to enhance aging workers' productivity and longevity in the workforce.