If you have ever broken an arm and had to wear a cast or splint for a few weeks, you will be familiar with the alarming loss of muscle and uneasy feeling of weakness experienced after removing your cast. Most people do not do much exercise while a broken arm is healing and can struggle with this loss of muscle, known as "atrophy," and weakness for many weeks after the injury.
Broke your arm? Exercise the other one to strengthen it
Source: Medical Xpress