High-speed power training in older adults: a shift of the external resistance at which peak power is produced.

Abstract

Studies have shown that power training increases peak power (PP) in older adults. Evaluating the external resistance (% 1 repetition maximum [1RM]) at which PP is developed is critical given that changes in the components of PP (force and velocity) are dependent on the %1RM at which PP occurs. The purpose of this study was to compare the changes in PP (and the external resistance at which PP occurred) after 12 weeks of high-speed power training (HSPT) vs. traditional slow-speed strength training (SSST). Seventy-two older men and women were randomized to HSPT at 40% of the 1RM (HSPT: n = 24 [70.8 ± 6.8 years]); traditional resistance training at 80% 1RM (SSST: n = 22 [68.6 ± 7.8 years]); or control (CON: n = 18 [71.5 ± 6.1 years]). Measures of muscle performance were obtained at baseline and after the 12-week training intervention. Changes in muscle power and 1RM strength improved similarly with both HSPT and SSST, but HSPT shifted the external resistance at which PP was produced to a lower external resistance (from 67% 1RM to 52% 1RM) compared with SSST (from 65% 1RM to 62% 1RM) (p ≤ 0.05), thus increasing the velocity component of PP (change: HSPT = 0.18 ± 0.21 m·s; SSST = -0.03 ± 0.15 m·s) (p ≤ 0.05). Because sufficient speed of the lower limb is necessary for functional tasks related to safety (crossing a busy intersection, fall prevention), HSPT should be implemented in older adults to improve power at lower external resistances, thus increasing the velocity component of power and making older adults safer in their environment. These data provide clinicians with the necessary information to tailor exercise programs to the individual needs of the older adult, affecting the components of power.