While some sore muscles are to be expected when exercising -- especially if you're doing something new or more strenuous than usual -- you shouldn't ignore pain and swelling during or after exercise, especially if it persists or worsens. While it's uncommon, there is a neuromuscular condition called chronic exertional compartment syndrome. In this condition, repetitive activity in a muscle area (or compartment) swells and inhibits blood supply to the muscles. If left undiagnosed, the exacerbated condition can cause potentially permanent injury to nerves and muscles.

Symptoms of the condition are pain and swelling during exercise. Initially the symptoms subside with rest, but as the condition worsens the pain and swelling take longer to go away. Other symptoms include aching, pressure, numbness, and muscle weakness. Arms and legs are most commonly effected. Because it often goes undiagnosed, accurate numbers of cases are unknown. The condition primarily affects young athletes.

There's no need to overreact to mild muscle pain while exercising. Chronic exertional compartment syndrome is uncommon, after all. But if you notice a pattern with pain and swelling and if your symptoms worsen with time, visit your doctor. It's better to be safe than sorry.

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