Sex Differences in Lower-Limb Strength Qualities Among Recreationally Active Adults: Implications for Neuromuscular Profiling

Although neuromuscular profiling based on the assessment of multiple strength qualities has received increasing attention, most available evidence derives from athletic populations, leaving limited population-specific descriptive data for recreationally active adults. The aim of the present study was to compare multiple lower-limb strength qualities between recreationally active males and females and provide population-specific descriptive data relevant to neuromuscular profiling. Forty-five male and forty-six female recreationally active adults performed a countermovement jump (CMJ), 10/5 repeated jump test, isometric mid-thigh pull (IMTP), and seated isometric plantarflexion strength test. Dynamic strength index (DSI) was calculated as the ratio of CMJ to IMTP peak force, while reactive strength index (RSI) was calculated as the ratio of jump height (JH) to ground contact time (GCT). DSI was smaller (d = −0.59, 95% CI: −1.00, −0.12, p = 0.011) in males (0.66 ± 0.11) than in females (0.72 ± 0.10). IMTP relative peak force was significantly higher (d = 1.42, 95% CI: 0.91, 1.85, p < 0.001) in males (36.97 ± 5.59 N/kg) than in females (30.00 ± 4.10 N/kg). However, isometric plantarflexion relative peak force in the seated position did not significantly differ (d = −0.19, 95% CI: −0.57, 0.22, p = 0.377) between males (16.02 ± 2.37 N/kg) and females (16.50 ± 2.84 N/kg). RSI was significantly higher (d = 0.85, 95% CI: 0.39, 1.26, p < 0.001) in males (1.20 ± 0.35) than in females (0.91 ± 0.32). Males demonstrated greater reactive strength performance and relative maximal strength of the hip and knee extensors than females, whereas relative seated plantar flexor strength was comparable between sexes. The present study extends the available comparative data on strength qualities in recreationally active adults and suggests that comprehensive assessment of multiple strength qualities may help characterize potential training priorities in this population.