Resistance Strength Training for Knee Osteoarthritis

Exercise is important for patients with knee osteoarthritis (OA). Strength training has been shown to help younger adults with OA. But how important is this type of exercise for older adults with knee OA?

In this study, physical therapists from Taiwan compare the effects of low resistance exercise to high resistance exercise. Three groups of patients over the age of 50 were included. Everyone in the study was diagnosed with knee OA affecting both knees.

Group one received low-resistance exercise. Low-resistance refers to low weights (load) with many repetitions. In this study, group one did 10 sets of 15 repetitions of each exercise. The weight used was determined by their baseline level of strength at the start.

Group two completed a high-resistance exercise program. They used more weight with fewer repetitions (eight) and fewer sets (three). Everyone did three training sessions every week for eight weeks. The exercises were prescribed and supervised by an experienced physical therapist. Group three (control group) did no exercise.

Results were measured in terms of pain, function, and walking time. Walking was assessed on level ground and while going up and down stairs. Pain was measured for several separate activities. These included walking, sleeping, sitting, and standing.

Function was a measure of general activities such as bathing, housework, and every day tasks. Strength was measured using a special testing tool called an isokinetic dynamometer. All measures were taken before and after the exercise treatment.

The authors reported at the end of the study that both exercise groups had less pain and had improved in strength. Walking speed was also increased on flat and uneven ground. The high-resistance group got better results than the low-resistance group. But it wasn't enough difference to be considered significant.

There were a few patients who could not handle the higher level resistance program due to increased knee pain during the exercises. No change in any measure was observed in the control group.

The results of this study support outcomes of other studies that show strength training reduces pain and improves function in older adults with knee OA. Improving muscle strength around the knee increases general knee joint stability. This is important when it comes to functional activities such as getting up out of a chair and walking or climbing stairs.

For those patients who can handle high-resistance training, the exercise program takes less time than low-resistance exercise training. Training programs for knee OA should also include agility tasks, balance training, and aerobic conditioning.



References: Mei-Hwa Jan, PT, MS, et al. Investigation of Clinical Effects of High- and Low-Resistance Training for Patients with Knee Osteoarthritis: A Randomized Controlled Trial. In Physical Therapy. April 2008. Vol. 88. No. 4. Pp. 427-436.