*LEFT ARM BROKEN? EXERCISE YOUR RIGHT!*

FITNESS : IF YOU sprain an ankle or break a wrist this summer and cannot use one of your limbs, the muscles there will weaken and shrink - unless you exercise those same muscles in your other limb.

According to a fascinating new study, working out the muscles on one side of your bodies can keep the muscles on the other side strong and fit, even if we do not move them at all.

The findings has implications for injury recovery and also underscores how capable and confounding our bodies can be.

Many of us - or a family member - will at some point break a bone, tear a ligament or experience neurological problem such as a stroke that makes it impossible to move an arm and or leg normally.

When the limb is immobilized, its muscles will atrophy, losing size and strength, a process that begins within days or even hours of injury.

There have been hints, though, that exercising one limb can affect the other. In past studies, when someone pedals a bike with one leg or lifts weights with one arm, muscles in the other limb often contract, development known as  mirroring.

But in most of those experiments, the unusual limb was not completely immobilized  with a cast and scientists did not focus on specific muscles, making it difficult to know whether exercising certain muscles in one limb affects all muscles in the other or only some.

So for the new study, which was published in April in the Journal of Applied Psychology, researchers from the  University of  Saskatchewan in Saskatoon gathered 16 male and female college students and closely examined their wrists.

Using ultrasound and CT scans, the scientists determined the precise dimensions of two separate sets muscles in that joint. : the extensors, which move the wrist back and away from the body; and the flexors, which pull it in, toward the forearm.

The researchers also tested each volunteers wrist strength using a weight machine for the hands.

Then they covered each student's left forearm and wrist with a hard cast to freeze the wrist in place. [All of the students were right-handed].

Half of the students were then asked to go on with their normal lives, ignoring the cast as much as possible and not exercising their arms.

The other eight students, though, began a workout program that targeted the  flexor  muscles in their wrists. Using a small,    viselike weight machine, they completed the multiple, strenuous eccentric contradictions of those particular muscles.

The Honor and Serving of the Latest Operational Research on Body, Health and Healing continues to Part 2. !WOW! thanks Gretchen Reynolds.