Isokinetic strength training: comparison of daily and three times weekly patterns.

Isokinetic exercise programs were compared as to the number of times per week subjects performed the exercise. Isokinetic exercise of the right knee extensors was performed on 23 female subjects between the ages of 18 and 24 who had no history or evidence of knee pathology. Pre- and post-tests included maximum isometric and isokinetic torque measurements of both the right and left knee extensors. Weekly strength testing was also done. One group performed the isokinetic exercise (3 sets, 8 repetitions per set at 10 rpm) daily for five days; one group performed the same isokinetic exercise protocol every other day, three times per week. The experimental period lasted six consecutive weeks. Strength gains of the exercised leg were significant in both groups but no significant differences in strength gains were found between the two groups after a period of six weeks of exercise, supporting the rationale for offering exercise programs three times weekly. In addition, strength gain curves were plotted weekly for the six week period. The average strength gain curves for both exercise groups as tested isometrically or isokinetically showed a decrease in strength between the second and the third week, which was not statistically significant but which was consistent in all subjects.