A team of researchers at the University of Sydney, Australia sought to determine whether the intensity of explosive resistance training enhances the contribution that muscle force and contraction speed make to improving peak power.
Peak power is the power output produced for a relative intensity (as determined by a percentage of the maximum intensity someone can reach during resistance training–the so-called 1RM). Traditional resistance training is high-intensity but slow speed or velocity and has been proven to improve muscle strength. Explosive resistance-training, on the other hand, uses a high load as well but it is lifted as quickly as possible. This has also been determined to be effective in increasing muscle strength. The researchers studied 112 healthy older adults between ages 63 and 75 divided into 3 training intensity groups: low-, medium-, and high-intensity explosive training. All groups trained for 8-12 weeks, twice a week. They concluded that improvements in peak power resulted mainly from improvements in force rather than speed. Further, they corroborated their earlier findings, that high-intensity training best improved muscle strength and endurance but low-intensity best improved balance performance. All three levels of intensity seem to have the same relative effect on peak performance.
To your health,
de Vos, N.J., Singh, N.A., Ross, D.A., et al. (2008). Effect of Power-Training Intensity on the Contribution of Force and Velocity to Peak Power in Older Adults. Journal of Aging and Physical Activity, 16(4), 393-407.