Who wants to sit on the sidelines? Exercise is for the actively-minded, not for wallflowers. So protect your workout routing and stay injury-free with these five moves.

Backs, knees, elbows, and rotator cuffs are common areas for exercise injury. You can guard yourself against injury by strengthening these areas. Warm up with at least 5 minutes of mild cardio before trying any of these exercises.

• Rotator Cuff: Tie one end of an exercise band to a doorknob and hold the other end in your right hand. Hold your arm bent; elbow at your side and lower arm across your abdomen. Keeping the band taut, rotate your hand while moving your arm back and forth across your abdomen. Repeat on other side.
  
• Elbow: With elbows at your side, bend your arms and hold a light 2-3 pound weight in each hand. Bend your hands at the elbow, hold, then release. Repeat the motion with palms down, to the side, and palms up.
  
• Back: Here are two moves to help strengthen your back. The Superman: Lie on your belly, arms straight out in front of you. Raise your right arm and left leg a few inches, hold and release. Repeat on other side. Or, try raising both arms and both legs. Ab crunches can also minimize the risk of back pain.
  
• Knee: Lie on your back with your left leg bent and arms at your sides. Lift your right leg, hold for a few seconds, release. Repeat on the other side.

Prevention has more details on each move.