(Reuters Health) - High-intensity resistance and impact training (HiRIT) may improve bone and muscle strength in select postmenopausal women with osteoporosis, according to a small study in Australia.
Some researchers and clinicians specializing in bone health caution, however, that the evidence for patients with osteoporosis to engage in these types of exercises is insufficient to go against the current osteoporosis exercise guidelines, which recommend only moderate-intensity exercises because heavy training might be hazardous to fragile osteoporotic bones.
“Certainly, this study demonstrated some signal for bone that HiRIT may well make a difference, but this study was not rigorous enough (nor) had a sufficient number of participants to alter in any way the current guidelines,” said D. Lee Alekel, director of the Osteoporosis and Metabolic Disorders of Bone Program at the U.S. National Institute of Arthritis and Musculoskeletal and Skin Diseases Medicine in Bethesda, Maryland, in an email.
For the new study, researchers analyzed data from the larger Lifting Intervention for Training Muscle and Osteoporosis Rehabilitation (LIFTMOR) Trial on 101 postmenopausal women age 58 or older. For eight months, half of the women did twice-weekly 30-minute sessions of supervised HiRIT that included deadlifts, overhead presses, squats and jumping chin ups with drop landings.
The other half formed a comparison group, and for eight months they did unsupervised, twice-weekly 30-minute low-intensity exercise at home.
All the participants had bone mineral density testing with a special type of X-ray called a DXA scan before and after the eight-month training program to assess changes in their bone mineral density (BMD), or bone health, at the spine and the femoral head at the very top of the thigh bone that meets the hip.
“I was very pleasantly surprised by our novel and very positive outcomes,” senior study author Belinda Beck told Reuters Health in an email. “I had concerns that heavy loading might be hazardous to an osteoporotic spine, but it wasn’t,” said Beck, who directs The Bone Clinic at Griffith University’s Menzies Health Institute in Queensland, Australia.
By the end of the study, the HiRIT participants increased BMD in their spines by an average of about 3 percent and increased hip BMD by 2.2 percent. In the comparison group, women lost an average 1.2 percent of spinal BMD and lost more than 2 percent at the hip, researchers report in the Journal of Bone and Mineral Research.
The benefits of bone density improvements at the femoral neck translate into stronger hips, Beck said. Women in the resistance group also had a 40 percent improvement in back and leg extensor strength, which Beck said helped improve their posture and reduce their risk of falls.
Ethel Siris, director of the Toni Stabile Osteoporosis Center of Columbia University Medical Center and New York Presbyterian Hospital, who was not involved in the research, said the benefit of exercise is that it makes people physically stronger so they can prevent falls.
She cautioned that patients with osteoporosis or osteopenia should do highly individualized exercise based upon their overall condition that is safe.
“You don’t want someone with poor bone health to overdo repetitions because they can get a stress fracture,” Siris said in a phone interview.
Bones naturally deteriorate with age, but 10 million Americans, 80 percent of whom are women, have osteoporosis, a debilitating condition in which their BMD is significantly lower than normal. Their bones become so weak and brittle they can break during a fall, or in extreme cases, from even a sneeze or minor jolt. People with osteopenia have thinning bones and are at risk for osteoporosis.
HiRIT training should be supervised by adequately trained professionals to ensure correct technique and appropriate progressions, as well as to minimize injuries, Beck said.
“I think this study warrants follow-up using HiRIT because it may well provide sufficient stimulus to evoke a bone response, but this would need to be tested in a larger sample with more rigorous study design,” Alekel said.
SOURCE bit.ly/2kqlSYJ Journal of Bone and Mineral Research, online October 4, 2017.
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