Effect of power-training intensity on the contribution of force and velocity to peak power in older adults.
OBJECTIVE
To determine the effect of training intensity on the contributions of force and velocity to improvements in peak power (PP) after explosive resistance training in older adults.


METHODS
112 healthy older adults (69 +/- 6 yr) were randomized to explosive resistance training at 20% (G20), 50% (G50), or 80% (G80) maximal strength (1-repetition maximum) for 8-12 wk (twice weekly, 5 exercises, 3 sets of 8 explosive concentric/slow eccentric repetitions) using pneumatic resistance machines or a nontraining control group (CON).


RESULTS
Force at peak power (FPP) increased significantly and similarly among training groups compared with CON. Velocity at peak power (VPP) did not improve significantly and remained similar between all groups. Force contributed significantly more to PP production in G80 and G50 than in CON. The change in PP was independently predicted by changes in fat-free mass in G80 and by changes in both FPP and VPP in G50 and G20.


CONCLUSIONS
Explosive resistance training in older adults results in the ability to produce higher PP outputs with heavier loads without loss of movement velocity. Moderate- to high-intensity training induced a greater relative contribution of force to PP production in this cohort.
de Vos
Nathan J
NJ
Faculty of Health Sciences, University of Sydney, Sydney, NSW, Australia.
Singh
Nalin A
NA
Ross
Dale A
DA
Stavrinos
Theodora M
TM
Orr
Rhonda
R
Fiatarone Singh
Maria A
MA
D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D001823:Body Composition; D005080:Exercise Test; D005260:Female; D006801:Humans; D008297:Male; D009119:Muscle Contraction / Q000502:physiology*; D053580:Muscle Strength / Q000502:physiology; D018482:Muscle, Skeletal / Q000502:physiology*; D010865:Pilot Projects; D055070:Resistance Training; D014891:Weight Lifting / Q000502:physiology*