Strength training improves hand grip and arm function in people who have suffered a stroke without causing increased muscle spasticity or pain, according to combined data from multiple studies.

Stroke commonly weakens muscles and may temporarily cause muscle spasm and pain.

There is some controversy surrounding strength training in stroke patients, as some rehabilitation groups feel that strengthening stroke-weakened muscles will also increase spasticity and pain. But that’s not what Dr. Janice J. Eng and Dr. Jocelyn E. Harris, of University of British Columbia in Vancouver, Canada, found.

They pooled results from 13 studies that recorded how strength training exercises, versus no strengthening intervention, affected overall arm strength and function in 517 stroke patients with mild to moderately impaired movement of the upper limbs.

On average, strength training lasted for about one hour on 2 to 3 days a week for 4 weeks, although some of the training periods extended as long as 19 weeks. Most interventions used small weights, resistance bands, and gym-type pulley weights to build muscle.

The combined results suggest, “strengthening does not increase spasticity on a permanent basis,” Eng told Reuters Health in an email. Rather, strengthening may actually reduce muscle spasticity, she added.

None of the studies analyzed reported side effects and those that measured spasticity prior to strength training reported no increase in spasticity over the course of training.

In six studies (a total of 306 participants), strength training led to moderate or large improvement in hand grip strength, Eng and Harris report.

In 11 studies (a total of 465 participants) training resulted in a small improvement in arm function.

However, five studies involving 210 participants showed no improvement in activities of daily living, for example picking up a small object. This finding, Eng said, calls for a re-examination of stroke rehabilitation efforts to “ensure that strength training not only improves function, but also activities of daily living.”

SOURCE: Stroke, January 2010