A new research has found that regular weight-training regime may help treat rheumatoid arthritis.
The study, which included 28 patients, found that those who pumped iron saw improvements in basic physical function, such as walking.
Researchers at Bangor and Gwynedd Hospital said that such high intensity exercising could play a key role alongside drug treatment.
But the experts said the exercise regime would not be appropriate for all patients.
Rheumatoid arthritis is mainly a disease that affects the joints, but a less well known symptom is that it also severely reduces muscle mass and strength and this occurs even among patients whose disease is well managed.
Those with the condition are often given mild home exercises to do to stop their joints stiffening and becoming painful.
The researchers split the 28 participants into two groups to test how effective the weight training was. One group did regular weight training for 24 weeks, while the others did the less strenuous standard home exercise regimes.
They found physical function improved by 20 percent to 30 percent in the group doing weight training. Strength also increased by nearly 120 percent.
The high intensity training was found to increase the levels of an insulin-like growth factor (1GF-1) and insulin-like growth binding protein 3 - both of which promote the growth of muscles, bone and cartilage.
Study leader Dr Andrew Lemmey said muscle loss was a major contribution to the disability associated with the condition.
"Lifting, carrying, walking, climbing stairs are impaired. It is logical that if you can restore muscle, that strength and consequently functional capacity will also be restored. And this is what we have found," the BBC quoted Lemmey as saying.
"In fact, the improvements in function were so significant that following training these patients with established RA were performing as well as or better than healthy individuals of the same age and sex," he added.
The study was reported in the Arthritis Care and Research journal.