Some people have got very short hamstrings. Unfortunately, I’m one of them. There are a number of ways to stretch the 3 hamstrings, but the way I found the most effective is to lie flat on your back with a towel rolled up under the small of your back, supporting the lumbar region. Trying to keep as still as possible, raise your right knee and pull it toward your chest. Try on one side for about 10 minutes on alternating legs for 30 minutes a night. If this exercise is done every night after a hot shower, you’ll notice the difference after 4 weeks. This will initially feel very uncomfortable but, it will become a piece of cake as the 3 hamstring muscles increase in length.