Many gyms have a hamstring machine that fixes your body in one position while you perform leg flexion against a resistance. Although this method of isolation training develops hamstring size and physical strength, it does very little or nothing to improve functional movement patterns that are vital for sports and daily activities, according to Dr. Nicolas Campos.
Types of Hamstring Machines
The seated hamstring machine fixes your body in an upright seated position. You place your lower calves and heels against a padded lever that is attached to a weight and pulley system and your knees beneath a padded support that keeps your thighs from moving. You flex your leg -- or bend your knee -- to exercise your hamstrings.
In the prone hamstring machine, you lie face down on a platform with your lower calves and heels fixed on a padded lever and your hands holding a support near your head. Like the seated machine, you flex your legs up to lift the weight stack.
The leg press machine works your entire legs, including your hamstrings. You sit on the machine with your feet pressed against a weight plate, and you push the plate away from you by extending your knees.
Your hamstrings are made up of the biceps femoris, semitendinosus and semimembranosus. They work with other leg and hip muscles to flex your knees and extend your hip joints. In sports and daily activities, such as walking and climbing stairs, the hamstrings serve as a force decelerator that controls the rate of leg extension and flexion and body movement, according to the National Academy of Sports Medicine. This helps you reduce leg and joint strain and prevent falls.
Potential for Muscular Imbalance
Heavy reliance on the hamstring machine can reduce your ability to move well, increase injury potential in sports, and reduce core stability and strength. If your hamstrings are over-stimulated via exercise, your buttocks become less active. Your hamstrings will compensate for hip weakness to perform the work that your buttocks are supposed to do, such as hip extension and stabilization. By over-relying on your hamstrings, you increase your risk for hamstring strain, hip stiffness and low back and knee pain.
Instead of using the hamstring machine, you can perform basic body weight exercises to improve hamstring strength and function. These include squats, step-ups, lunges, sprints, stair-climbing, rock-climbing and jump roping. This allows the hamstrings to work in coordination with the rest of your body to produce efficient, safe movement patterns.