MSN: Why you're not sore after working out (and why that's okay) We asked a sports MD and a physical therapist. Reviewed by Traci Copeland Fact checked by Anna Harris Muscle soreness after exercise indicates micro-injury, which is critical for muscle growth and ... Yahoo: 20 best hamstring exercises to tone your legs and relieve knee pain 20 best hamstring exercises to tone your legs and relieve knee pain Your legs are an amazing collection of bones and muscles.

Understanding the Context

But if something goes a bit wrong, they can hurt and make it hard to move around. Find out what you should know with this WebMD slide... Leg, limb or appendage of an animal, used to support the body, provide locomotion, and, in modified form, assist in capturing and eating prey (as in spiders and insects). In four-limbed vertebrates all four appendages are commonly called legs, but in bipedal animals only the lower two are so called.

Key Insights

From the large, strong muscles of the buttocks and legs to the tiny, fine muscles of the feet and toes, these muscles can exert tremendous power while constantly making small adjustments for balance --- whether the body is at rest or in motion. Your legs are powered by four key muscle groups: gluteals, quadriceps, hamstrings, and calves. "While each of these has its own purpose, in their location, size, and actions, they work together to move our bodies from one place to the next," says Smith.