The stretch board: a simple yet effective device to stretch calves and hamstrings
A simple smooth wooden board and gravity can be used for a very good and effective calves and hamstrings stretch. Place a the board, which should be large enough for both of your feet, directly at a free wall. Now elevate the side facing the room with a couple of magazines, the more magazines, the more intense the stretchwill be. Place a chair or someting comparable approximately 60-100cm in front of the board. The distance depends on the length of your arms. Stand on the board, best is to wear socks, and relax. Choose enough magazines under the board so that you heels are just slightly touching the board and let shoulders, buttock and both heels in contact with the wall. Try to relax and you will notice that after a while gravity will bring your heels in closer contact with the board. After approximately a minute end the stretch via an intense hamstring stretch: bend your self to the chair, hold it with both hands, maintain a slight arch in your back while you are bending forward, and let the movement only occur in the hip joints. This will lead to a very intense hamstring and calf stretch. Don't overdo! Try to relax for 20sec or so. And then slowly reverse the movement, using your hands to push yourself back to the wall. Do you notice a difference in the calves now? Are they in closer contact to the board now, in other word do you feel more weight on them? Step from the board, slowly. Walk around for a minute or so and your done.
A couple of additional points:
When in the stretch position, try to elevate your big toes. Does this lift your heels from the board, if so the flexor of the big toe, which runs also over the heel is shortened, place a thin board under the toes when you do the stretch the next time.
Do your feet tend to pronate in the stretch position, place a small board under the inner sides of the feet to cope with this tendency. Otherwise you are avoiding the full stretch.
You can use whatever stretching technique you like, slow pulsing movements, static stretching, PNF, you name it, but simple static stretching via gravity works well enough in my experience. When using PNF try the following technique. Press the front of you feet very lightly, with say 10% of the maximum force, in the board for a count of 10. Be very carefull not to lift the heels even if it is only a mm, now stop, take a deep breath and on a very slow exhalation try to relax and let your heels sink deeper in the board, hold for the planned stretching time.
This works best when administered on a daily basis. The warmer you are, the better but it works cold just as well if you chose the right height of the board elevation. Start with ~60sec plus the 20 sec hamstring stretch and increase the time every week for 15--30 sec. When you are around 2--3min it is not really necessary to add additional time, instead work one foot at a time. You can and should also add another magazine to the staple under the board every week. Give this a serious shot for 8 weeks or so.