A hamstring refers to one of the tendons that make up the borders of space behind the knee. It usually includes tendons of semitendinosus, semimembranosus, and biceps femoris. The main job of the hamstring is to extend the hip joint and flex the knee. Runners are more likely to have hamstring problems because of overuse.

Sometimes the pain is not experienced because it suddenly comes and goes i.e. it vanishes after the muscles warm up. Stretching in a wrong way may worsen the pain. The hamstrings are activated with increasing workout in activities involving sudden movements and jerks. Lack of movement may cause tightening of the hamstrings.

Hamstring flexibility is crucial for runners. Professional runners, workout under the supervision of certified trainers and hamstring flexibility yoga stretches form a major part of the flexibility stretches.

Amateur runners may make the mistake of not realizing the importance of these yoga stretches and will soon feel the adverse effects. Including yoga in your daily pre-running practice is absolutely essential to avoid injuries to the hamstrings.

A few yoga stretches for hamstring flexibility development are listed below:

• Forward bend - Stand straight with both legs together. Now slowly raise your hands and bend forward and try to touch your feet, maintain this posture for a few seconds and return to the start position. Repeat 3-4 times.

• Backward Bend - Stand straight with both legs together. Now slowly raise both your hands and bend backward as much as you can. Maintain this posture for a few seconds. Return to the start position. Repeat 3-4 times.

• Supine leg stretches (Supta Padangushthasana). - Lie down straight,. Now slowly raise the right leg with the knee straight. Try and grasp the thigh and stretch as much as you can. Repeat for the left leg. Repeat 3-4 times with each leg.

• Locust posture (Salabhasana) - Lie on your stomach, make fists of your hands and place them below you thighs, keep your head straight with chin on the floor and raise your legs as high as possible keeping them straight at the knees slowly. Repeat 3-4 times.

• Parvottasana - Lie flat on your stomach, both hands near your chest. Now raise your body slowly to form an inverted V (or mountain) with your hips at the highest position supported by your hands and feet. Maintain this posture for a few seconds. Return to the start position. Repeat 3-4 times.

• Seated Wide Legged Straddle (Upavistha Konasana)- Sit straight and open the legs out as wide as possible. Make sure that the toes are pointing towards the ceiling. Try and press the legs down to the floor as much as possible. Maintain the posture for a few seconds. Repeat 3-4 times.

There are a lot of other options too. Now all runners run along and plan a routine for a small hamstring yoga flexibility workout. Remember, in the long and hard run, flexible hamstrings are the greatest assets of a runner!