These are some great exercises to increase hamstring size.
A Romanian Deadlift is similar to regular deadlift, but will work the hamstrings harder. Instead of squatting down and keeping your back straight, you will bend forward at the waist and keep your knees slightly bent throughout the movement. Starting position: Stand holding a loaded bar, keep feet about a shoulder width apart, keep knees slightly up to a little more than slightly bent. Bend forward at the waist bring bar to about ankle level (less if you feel strain in the lower back) then come back up. This exercise works the hamstrings the most, but also greatly works the lower back and glutes.
You can use a lying or seated leg curl machine. Get into position on the machine, using a heavy but controlled weight, pull to contract the hamstrings. Hold the contraction for a two count and then release slowly. Return to the starting position just before the legs are completely straight.
This is best done on a lying leg curl machine. You may be fortunate to have a leg curl machine that is made specific for one leg at a time training, but they are hard to find. Use the same form as you would with a traditional leg curl, but one leg at a time.
With this exercise you need to lay down on your back on the floor. Place your legs how they would be with a standard crunch position, except you will have a heavy plate under your feet. Pull and push the plate against the floor with your feet. The plate will start out away from you, it will come close, sliding against the floor, as you bring the back of your feet closer to your butt.
This should be performed after you have already started working the hamstrings on a different exercise, that way the hamstrings will try to do more work than the quads. Place the feet up very high on the sled (foot platform) and bring the weight down deep and slow. Push back up, do not lock the knees (which should be difficult to do on this exercise anyway), you will feel most of the weight being controlled by the hamstrings.
A beginner should choose 2-3 of the listed exercises with 3 sets of 10 reps each. Lift heavy but use strict form. Always check with your doctor before staring a new exercise program.
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