posted 10/07/02
High-intensity weight training coupled with a moderate
weight-loss program can help older men and women with type 2 diabetes to improve
their blood sugar control and also boost their muscle strength and lean body
mass, researchers report.
The added muscle is particularly beneficial to
people with diabetes, according to Dr. David Dunstan, the study's lead author,
because muscles are "major clearance sites" for circulating blood sugar, or
glucose. In type 2 diabetes, the body loses its ability to respond to the blood
sugar-regulating hormone insulin, so high levels of glucose can build up in the
blood.
Dunstan is director of physical activity programs
and research at the International Diabetes Institute in Victoria, Australia.
The magnitude of the response, noted study
co-author and institute director Dr. Paul Zimmet, was surprising. "The effects
of the resistance training program were as great as those typically seen with
drugs for diabetes," he explained.
The researchers assigned 36 people aged 60 to 80
to one of two exercise groups: high-intensity resistance training and moderate
weight loss; or moderate weight loss plus a control program, for 6 months. Study
participants in the control group did stretching exercises instead of lifting
weights.
The goal of the high-intensity lifting program is
to train with weights that are around 80% of the maximum poundage a person can
lift for one repetition. The weight-lifting patients did nine different
exercises three times a week that worked muscles in their legs, arms and
abdomen, and were closely monitored by staff.
A test of long-term blood sugar control showed
significant improvements in the weight-lifting group after 3 months of exercise,
and improved further by 6 months. People in both groups lost weight and fat, but
the weight-lifters showed gains in lean body mass while those who didn't lift
weights showed losses.
Encouraging high-intensity weight lifting for
people with diabetes could reduce the risk of diabetes complications--which can
include eye and nerve damage, as well as kidney problems--in the long term,
Dunstan said. The more tightly blood sugar is controlled, the less likely
complications are to develop.
These results, said Dunstan, "support the recent
recommendations of the American College of Sports Medicine that resistance
training should be included as part of a well-rounded exercise program for all
people with type 2 diabetes." Patients should consult their doctor first before
beginning training, he added.
Dunstan encourages gym owners to make gyms more accommodating to older people so it will be less intimidating for them to work out. "Who knows--for many gymnasiums this could be a totally untapped market," he said.
Source: Diabetes In Control Dot Com:
Diabetes Care 2002;25:1729-1736.