Strength training -- it's not just for muscle-heads anymore. A study published last month in the journal Medicine & Science in Sports & Exercise found that although older women gained muscle strength after an eight-week strength-training program, they showed little improvement in muscle power, or how much force is generated in a given amount of time. The latter is indicative of having fewer fast-twitch muscle fibers -- engaged during sprinting, kicking a ball or getting up and down from a chair.
The study included 49 inactive women, half younger (18 to 33 years old) and half older (65 to 84 years old). A few from each group served as a control, not altering their normal routine. The training groups engaged in an eight-week strength-training program consisting of knee-extension exercises that concentrated on quadricep muscles. The women did the exercise at a normal speed to increase muscle strength, then again faster, to increase muscle power.
The younger and older women showed about a 12% increase in muscle strength, which Dain LaRoche, lead author and assistant professor of exercise science at the University of New Hampshire, calls "a huge benefit."
But when it came to muscle power, the young women logged a 35% increase, while the older women had only a 9% increase. Part of that, according to the study, could be that the strength-training program didn't provide enough stimulus.