Load- and velocity-specific adaptations to lower-body maximal strength training (MST), hypertrophy training (HT) and explosive strength training (EST)

We compared the effects of three strength training methods on squat performance; maximal strength training (MST), hypertrophy training (HT) and explosive strength training (EST). MST and EST were workload-matched, whereas HT was performed at higher volume. Fifty-eight moderately trained males (n = 29) and females (n = 29) were allocated to (1) MST-4 × 4 repetitions squats at ≥ 85% of one repetition maximum (1RM), (2) HT-3 × 8-12 repetitions squats at ∼70–80% of 1RM, (3) EST-4 × 6-7 unloaded squat jumps (SJ), (4) Control (CON). MST, HT and EST performed three sessions/week for eight weeks. Squat 1RM strength, SJ rate of force development (RFD) at 50%, 30% and 0% of squat 1RM (RFDSJ50%, RFDSJ30% and RFDSJ0%), SJ- and counter movement jump (CMJ)-height and leg lean mass were examined. MST and HT improved squat 1RM (+ 20.7% and + 18.2%) more than EST (+ 10.9%) (all p ≤ 0.01) and CON (all p ≤ 0.001). MST and HT improved RFDSJ50% (+ 21.7% and + 14.3%, all p ≤ 0.001), RFDSJ30% (+ 17.8% and 14.0%, p ≤ 0.001–0.01) and RFDSJ0% (+ 12.3% and + 11.4%, p ≤ 0.01–0.05), while EST and CON did not. EST improved SJ-height (+ 2.2 cm) and CMJ-height (+ 1.7 cm) (all p ≤ 0.001) to a similar extent as MST (+ 2.2 cm and + 2.3 cm, all p ≤ 0.001) and HT (+ 2.0 cm and + 1.6 cm, all p ≤ 0.01). MST and HT led to improvements across all measured squat and jumping variables, whereas EST improved jump performance under conditions of low external load and high velocity. Improved jumping performance following MST and HT seems to rely largely on changes in muscle strength, whereas for EST, other mechanisms not assessed in this study may play a greater role.