Comparison between Quadriceps Muscle Strengthening on Land and in Water

Abstract

Summary A study on healthy young women compared progressive resistance quadriceps muscle strengthening in water and on land. The water (n = 19) and the land (n = 18) groups exercised five times a week for eight weeks (using a modified DeLorme protocol). A third group of 16 subjects were unable to attend exercise sessions and while not forming a strict control group, provided some data from a non-exercising group for comparison. All three groups underwent isokinetic quadriceps testing at 60°/s and 270°/s at weeks 0, 4 and 8. The ten repetition maximum (10 RM) of the quadriceps of the exercise groups was measured before and weekly during the trial. Pre- and post-trial, as well as weekly intra-trial questionnaires were completed, seeking information on aspects such as exercise-induced pain. There were no significant differences between the water and the land exercise groups on isokinetic or 10 RM testing. Significantly more subjects in the land group complained of pain while exercising. There were no significant differences in the strengthening observed following progressive resistance exercise using home-made water-weights in water and using sandbags on land. Isotonic testing using the 10 RM showed significant quadriceps strengthening in both exercise groups, whereas isokinetic testing showed no increases over the eight weeks. There was no correlation between the 10 RM and isokinetic extension values. The results suggest that isokinetic testing cannot be used to measure isotonic muscle strength in this population. A study on healthy young women compared progressive resistance quadriceps muscle strengthening in water and on land. The water (n = 19) and the land (n = 18) groups exercised five times a week for eight weeks (using a modified DeLorme protocol). A third group of 16 subjects were unable to attend exercise sessions and while not forming a strict control group, provided some data from a non-exercising group for comparison. All three groups underwent isokinetic quadriceps testing at 60°/s and 270°/s at weeks 0, 4 and 8. The ten repetition maximum (10 RM) of the quadriceps of the exercise groups was measured before and weekly during the trial. Pre- and post-trial, as well as weekly intra-trial questionnaires were completed, seeking information on aspects such as exercise-induced pain. There were no significant differences between the water and the land exercise groups on isokinetic or 10 RM testing. Significantly more subjects in the land group complained of pain while exercising. There were no significant differences in the strengthening observed following progressive resistance exercise using home-made water-weights in water and using sandbags on land. Isotonic testing using the 10 RM showed significant quadriceps strengthening in both exercise groups, whereas isokinetic testing showed no increases over the eight weeks. There was no correlation between the 10 RM and isokinetic extension values. The results suggest that isokinetic testing cannot be used to measure isotonic muscle strength in this population.