Build Bigger, Muscular Thighs With Hack Squats

Proper thigh training is really tough work. Most guys who have a bit of a sadistic streak love to work the thighs. These are the ones who actually look forward to pounding their thighs rep after rep and set after set, until the buckets must be retrieved so they can unload their last meal. Now, I like hard work as much as the next guy, but puking isn’t my idea of a great workout. Instead, if you’re a bit more on the sane side, you can still develop great thighs with balanced, hard, strong and thick muscle bellies without having to enter psychotherapy to get you through your next workout.

There’s no doubt that for sheer muscle mass, there are few exercises more effective than barbell squats. But, as good as squats are, to obtain the best underpinnings possible, you need to have thighs with muscle bellies that seem to have been chiseled from a granite surface. One of the best ways to do this is to continuously activate your thighs throughout the complete set (constant tension). Single-leg hack squats induce constant tension by activating all of the muscle fibers continually throughout the set, but at the same time, it deprives the muscle of any opportunity for rest until the set is over. This makes the exercise a hard ride, but one with a great reward that after about three months, will unveil outstanding thighs. Hack squats can add a new dimension of chiseled hardness and muscle growth, especially in the mid-regions of the thighs.

Quadriceps Muscles

The anterior thigh consists of four major muscles collectively known as the quadriceps femoris (“quadriceps” or “quads”). These cover the anterior and lateral parts of the femur bone of the thigh. The quadriceps group is made up of three vastus and the rectus femoris muscles. “Vastus” is a Latin name meaning large or great. The three large vastus muscles are named to indicate their position on the thigh. The vastus lateralis muscle lies on the lateral (outer) part of the thigh over the lateral part of the femur bone. The vastus medialis covers the medial (inner) part of the thigh. The vastus intermedius is located intermediately on the femur bone, between the vastus lateralis and the vastus medialis, and covers the central and deeper parts of the thigh. The fourth muscle is the rectus femoris. The top part of this muscle attaches to the hip and it courses down the central portion of the thigh. All four muscles come together above the knee to attach to the patellar tendon. This attaches to the patella (kneecap) and the patellar ligament attaches the patella to the top part of the tibia bone just below the knee. Together, the quadriceps extend (straighten) the leg at the knee joint by pulling on the patella and through it, to the patellar ligament that’s attached to the lower leg (tibia bone). The rectus femoris also flexes the thigh at the hip joint by pulling the knee and thigh toward the chest. The rectus femoris muscle is a weak knee extensor when the hip is flexed because it’s mechanically unable to make a major contribution to force production when the hip is flexed (e.g., sitting). On the other hand, hack squats do a much better job because the hip is quite straight during much of the lift and during this time, the rectus femoris can be strongly activated.

Single-Leg Hack Squats

The best hack squat machines aren’t vertical, but they have a slight (approximately 15 degree) angle so that you’ll be leaning just a little backward during the lift. By leaning back, the hip joint is straighter and this stretches the rectus femoris slightly, improving its ability to extend the knee as you push from the bottom position. This angle also maintains tension better on the muscles throughout the exercise. You should make sure your shoes have a good rubber sole that will grip the foot platform securely. Because you’re doing a single-leg exercise, you won’t need to load super heavy weights. It’s unlikely that even if the shoulder pad isn’t extremely thick it will limit your exercise performance; nevertheless, the focus should be on your thighs and not your shoulders.

1. You should warm up the knees and thighs before beginning your thigh workout, including some stretches for the quadriceps and hamstrings. Even if you’ve just completed barbell squats, it’s wise to do a lighter set and some stretches before launching into the hacks with all of your effort. Hack squats should be positioned somewhere near the end of your thigh routine and certainly after leg presses or barbell squats.

2. Place your feet about 24 inches apart and no more than shoulder-width on the footplate. The toes should point forward. The feet should be placed far enough out on the footplate so your knee doesn’t extend beyond your toes when you descend into the bottom part of the lift.

3. Your shoulders should contact the pads with your knees slightly bent. Place your upper back firmly against the sliding back platform.

4. Release the safety stands, extend the knees and take the weight on your shoulders. One leg will take the weight and the other leg won’t work on the first part of the set. Remove the nonworking leg from the foot platform and flex the knee to about 90 degrees. The ball of the foot of the nonworking leg is moved to sit under your buttocks. Let the toes of this foot contact the floor of the base of the footplate to help you keep your balance.

5. Tighten the thigh of the leg to be worked then slowly lower the weight stack and control the descent by the forward foot. Keep your eyes up. The knee on the working leg will bend, but the knee should remain facing forward as you lower your hips toward the floor. The hip joint will flex during the decent.

6. Slowly control the lowering of your body as the back slide moves toward the floor. Keep your back against the sliding back platform and make sure your hips don’t come forward. Continue squatting downward until the knee joint of the working leg is about 90 degrees or a little less.

7. Allow the knee on the (nonworking) rear leg to bend so it approaches the footplate as your body is being lowered. It will be pointing toward the floor (not forward) as your body is lowered to the bottom position.

8. Don’t stop at the bottom, but immediately push upward so the knee on the working leg straightens. Push from the heels rather than the toes as the weight is moved upward. Continue to move upward until the knee of your working leg is just a few degrees from straightening completely (i.e., don’t lock your knee in the top position), and immediately go into the descent on the next repetition. The knee on the nonworking leg will also come up as the weight is lifted, but it will continue to project downward.

9. After completing one leg, rest for about two minutes, and then switch to the other leg. Complete the set with continuous tension on the working leg, rest another two minutes, and then switch back to the first leg.

It’s important to keep a fluid-smooth motion in both directions. This will maintain the constant tension on the thigh of the working leg throughout the entire set. It will also become somewhat fatiguing and painful because the muscle is accumulating a lot of metabolic by-products and it’s oxygen deprived due to the constant tension. Don’t rest at the top of the exercise as this will eliminate the constant tension on the muscles and the weight will be transferred away from your muscles to the thigh and leg bones.

You should never bounce into the bottom position, and avoid the exercise if you have a prior knee injury. However, if your knees are healthy and you would like the middle sections of your thighs to begin to take on hard contours with clear delineations between each of the muscle bellies, then hack squats may be just the right exercise for you.

This is a very tough exercise. As you work through each set, your thighs will scream for oxygen-saturated blood. Nevertheless, as you become mentally tougher, you’ll ignore their pleas for mercy and continue to pump and shock your thighs, repetition after repetition. Don’t expect this type of mental toughness to arrive overnight, but it will come. Start out with only a couple of sets, but if you really want to shock your thighs, try doing four sets of 15 or 20 repetitions using constant tension. Don’t strive for any strength records. Beware, though, the shock value is proportional to the pain of the exercise; but then, so is the value to your muscle quality.


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