Exercise has always played a crucial role in treating osteoarthritis, but views are beginning to change on what exercise regimens do the most good. Most recommendations to date have been for daily low-impact exercises, focusing on range of motion and strengthening. High-impact exercises, such as running and jumping, build bone density faster but often are viewed as too risky—leading to cartilage damage and joint injury in those with osteoarthritis and osteoporosis.
But as long as the osteoarthritis is not severe, adding some higher impact exercise might do more good than an exercise regimen consisting solely of low-impact activities.
Researchers at the University of Jyväskylä studied 80 women aged 50-66 with a diagnosis of mild knee osteoarthritis. In the study, published in the Journal of Bone and Mineral Research, half the group did low-impact exercise only, while the other half did a combination of low- and high-impact activities, including jumping and step-aerobics. After one year, the combo exercise group had increased bone mineral content in the neck, better leg extension force and improved dynamic balance compared to the control group.
Small amounts of high-impact exercise and careful supervision can increase bone density without damaging cartilage, says Riku Nikander, PT, PhD, professor at the university, in a Medscape article. “People who do high-impact [exercise] might have 20-30 percent stronger bones in their lower extremities. Animal experiments have shown that it should include movement—if possible, quite rapid movement. [This] is due to a fluid flow inside the bone that starts a cascade of events that leads to stronger bones.” Unfortunately, activities that require fast movements or quick changes of direction also pose the greatest risks.
The National Osteoporosis Foundation’s Clinician’s Guide to Prevention and Treatment of Osteoporosis recommends “weight-bearing and muscle-strengthening exercise,” and many rehabilitation and therapy programs are realizing the value of varied exercise programs that combine gentle exercises with short periods of supervised high-impact activities.
Attaining the right balance of exercise types also is an effective way to manage pain and reduce unnecessary medications. “Exercise is considered the most effective non-drug treatment for reducing pain and improving movement in osteoarthritis,” notes the Arthritis Foundation.