We struggle to find new exercise techniques that will elicit new growth from our static physiques. That’s especially true of our lower limbs. The hamstrings group, for instance, has only five exercises from which to draw its size: wide-stance squats, leg presses, lunges, leg curls and deadlifts. Of those five, the leg curl is used 75 percent of the time. To compound the problem, you can’t use enough weight on the machine to build much mass.
Fortunately, I have one beauty of an exercise that quite possibly could be the best of the best. Why? Because it will enable you to handle some serious weight. I call it the hips-off-hack-machine leg pull.
Good friend and former training partner Dennis Madsen and I came up with the idea from reading Kinesiology and Applied Anatomy by Rasch and Burke. I first came across this informative book while doing a seminar in Grand Rapids, Michigan. A fellow by the name of Jim Phillips stayed after the show to share something with me.
He said, ‘Larry, you go into so much detail on an exercise, I think you’d be interested in a textbook I used in physiology classes at the University of Michigan. Would you like to see it?’
‘Yes, I would,’ I said, with some interest. ‘I’m always looking for new ideas on training.’
It was loaded with training gems, and the featured models were right out of the pages of a ’60s bodybuilding magazine, including Paul Wynter, Bob Walker, Tony Sansone, Tommy Kono, Otis Johnson and Bill Golumbick.
I began reading about the action of two-joint muscles and stumbled onto Lombard’s paradox, named after the scholar W.P. Lombard, who was one of the first to analyze and clearly explain this phenomenon. He suggested that when you rise from a sitting position, the rectus femoris (top of the thigh) and the hamstring muscles (back of the thigh) spring into action. That may surprise you, as the rectus femoris and the hamstrings should neutralize each other’s actions so that no movement is possible. But they don’t.
So what does all this mean to those interested in finding a new way to build the hamstrings? If both the quads and the hamstrings are working while you’re doing something as simple as getting out of a chair, the question is how to devise an exercise similar to squats (the getting-up-out-of-a-chair motion) that pinpoints the hamstrings rather than the quads.
Dr. Rasch’s book spends several pages explaining that the rotational torque for each muscle is equal to the force of its pull multiplied by its perpendicular distance from the axis of rotation. The difference in the length of the lever arms has a lot to do with which muscle dominates. Which muscle group is going to work the most depends on the relative position of the hips and the knees.
The key to working the hamstrings is to position your hips and thighs so that you can pull with the hamstrings to help extend the knee rather than press with the quads. You obviously can’t play around with free-bar squats because you could injure your back or drop the weight. The hack machine, on the other hand, provides a perfect exercise for moving your hips with respect to your knees because balance is not in jeopardy. To turn the hack squat into a hamstring exercise, do the following: Place your feet high on the platform at shoulder width and turn your toes out about 45 degrees.
Once in position, slowly lower yourself to the low point. Then, right at the bottom of the movement, thrust your hips off the sled so your hamstrings have the mechanical advantage over your quads. Now try to pull your legs together to straighten them out.
Eureka! We have a new exercise for building hamstrings. Furthermore, it’s one on which we can use a lot of weight. The quads help you get down into position, but when you thrust your hips off the sled, you bring the hamstrings into action as you straighten out your legs. Concentrate on pulling your legs together to get back up into the starting position.
It’s not as difficult as it sounds. Experiment, and you’ll soon master the movement’then you’ll add some real size to your hams.
Editor’s note: To learn more of Scott’s unique techniques and become Larry Scott certified, call 1-800-225-9752 or visit www.larryscott.com.