But when it comes to our weight lifting, our sense of fun often deserts us. We do the same thing every session. Yet variety is just as important in strength training as it is in running.
Take it from an expert. Penn State University exercise physiologist William Kraemer, Ph.D., has studied resistance training for 25 years. In a recent nine-month study, Kraemer put one group of subjects on a lifting routine that consisted of the "standard" eight to 10 repetitions of several exercises three times a week.
A second group did the same exercises three times a week, but the amount of weight and number of reps changed each session. They lifted lighter weight 12 to 15 times in the first session, heavier weight three to five times in the second session and their normal amount eight to 10 times in the third session.
"Through three months the two groups showed equal and significant strength gains," Kraemer says. "But by four or five months, the first group began to plateau and didn't get stronger for the rest of the study period. Those who varied their workouts continued to see strength gains throughout the nine months."
So go ahead and change one of your weekly workouts. If you lift on Tuesdays and Thursdays, for example, go through your usual routine on Tuesday. Then on Thursday, do the same exercises you did on Tuesday, but do fewer reps than usual at a higher weight or more reps at a lower weight for each exercise.
You also might consider gradually adding new exercises and dropping others over time, or tinkering with the number of sets you do (that is, do fewer sets but more reps, or vice versa). Finally, remember to take a week off from lifting every couple of months to let your neuromuscular system recover.