The role of maximal strength and load on initial power production

Purpose: The influence of maximal strength, as measured by the maximal load lifted for one repetition (1RM), on power production in the initial 200 ms of the concentric phase for both rebound and nonrebound movements was inve stigated. We also investigated the effect of external load upon this relati onship. Methods: Twenty-seven male subjects (21.9 +/- 3.1 yr, 89.0 +/- 12.5 kg) were separated by previously determined bench press 1RM into high (100 .88 +/- 7.24 kg) and low (72 +/- 6.61 kg) RM groups. Concentric only bench presses and rebound bench presses were compared between and within groups t o note the effect of RM across external loads of 40%, 60%, and 80% 1RM, on instantaneous, mean, and peak power output. Results: The results of this st udy clearly indicated the enhancement of concentric motion by prior eccentr ic muscle action (336-1332% enhancement in the first 20 ms). Possessing a h igh RM augmented power production in the initial 200 ms of stretch-shorten cycle activity, across all the external resistances tested (P < 0.05). The temporal characteristics of this enhancement, however, differed across load s. That is, 80% 1RM loading showed a later time to peak enhancement (80 ms vs 20 ms). Interestingly, the influence of RM on concentric only motion in the initial 200 ms across the external resistances tested was found to be n onsignificant. Conclusions: The results suggest that the role of maximal st rength during initial power production between concentric and stretch-short en cycle activity differs, which has important implications for the trainin g of athletes.