Q Fit Bit Muscle …Are painful, but common and often manageable. I t’s happened before on occasion. From the bliss of sound sleep, you’re suddenly awakened by a painful muscle cramp in your lower leg. Lately, though, you’ve being awakened by leg cramps several times a week. Should you be concerned? Muscle cramps like this are fairly common among athletes and older adults. Many times they’re harmless. But they can sometimes be brought on by certain medications or they may indicate the presence of certain disorders. Muscle Movement Your muscles are made of many fibres that can contract and relax. This allows the fibres to shorten and lengthen according to the movement you’re making at the time.