The gracilis and biceps femoris -- the hamstring -- are important muscles, as they both attach to the pelvis and sandwich the knee. They affect simple activities such as sitting or climbing stairs. These muscles are also important in athletic activities like horse riding, hurdling, soccer and sprinting. The main actions of these muscles are to bend the knees and rotate the hips. An additional action of the biceps femoris is to extend the hip. They generally work together to create fluidity in movement of the legs.
Gyms have numerous machines that you can use to strengthen the gracilis and biceps femoris. To work both of these muscles, use leg curl machines and a multi-hip machine. To specifically strengthen the gracilis, a hip-joint adduction machine is recommended. Carefully follow the instructions that are attached to each machine.
At-home Exercise for Biceps Femoris
To strengthen and stretch the biceps femoris, perform a 90-degree leg lift. Lying with your back comfortably flat on your yoga mat, start with both legs bent. Straighten one leg onto the mat while slowly lifting the other leg with the exercise band wrapped around the sole of your foot. Lift as close to a 90-degree angle that you can get. By keeping your back and other leg as flat to the ground as possible, hold the position for up to a minute. Repeat this exercise three times, and do the other side. When lifting and releasing your legs, do not strain your head and neck. Keep them relaxed.
At-Home Exercise for Gracilis
To strengthen the gracilis, sit on your yoga mat in a simple cross-legged position. With a straight back, place one ankle on top of the opposite knee. Stack your shins one on top of the other and extend your feet. Inhale as you lengthen your torso and sit up straight. Exhale, hold the position for up to three minutes -- taking time to inhale -- and then exhale again. Repeat on the other side. Rotate from your hips and not your knees.
Tips and Considerations
Never do these strengthening stretches without warming up first, as sudden lengthening may cause more damage to already tight muscles. A warm-up can include anything that gets your blood flowing in your muscles. As long as you do between five and 15 minutes of moderate physical activity -- such as walking or stair-stepping -- these poses should be safe for you to enter into.
Work these stretches into your daily routine. If you meditate in the morning, sit in the gracilis position. When you are watching TV in the evening, have a friend help you into the hamstring stretch.