Written by Stephen E. Alway, Ph.D., FACSM
The Path to Strong & Muscular Quads
Machine Front Squats are the Way
Machine front squats are exceedingly brutal, but the pain is worth effort. Do them properly and consistently and your quads will grow.
Machine front squats hit the four quadriceps femoris (“quads”) muscles of the anterior (front) thigh.1 The fibers of the rectus femoris muscle runs from hip, along the front of the thigh to join the quadriceps tendon above the kneecap (patella). The rectus femoris extends the leg at the knee joint.2 The vastus medialis muscle covers the medial (inner) part of the thigh. This creates the “teardrop” area that is medial and superior to the patella (kneecap). The vastus intermedius muscle is positioned between the vastus lateralis and the vastus medialis muscle but it is deep to the rectus femoris muscle.2 The vastus lateralis muscle is positioned on the lateral (outer) part of the thigh. The three vastus muscles begin on the femur bone of the thigh, and attach to the upper border of the patella by the quadriceps tendon. The patella is attached to the tibia bone of the lower leg by the patellar ligament. As the muscles of the quadriceps shorten, they pull on the tibia bone to extend the leg (i.e., knee straightens) at the knee joint.2The three vastus muscles are not affected by hip angle, so they are active throughout the front squat.1
Machine Front Squats Protocol
1. Spend five minutes warming your knees before starting front squats.
2. Load the machine with the appropriate load.
3. Bend your knees slightly and position your shoulders under the pads. Your feet should be about shoulder-width apart. Bring your feet forward so that they are in front of your shoulders. This will guarantee that your torso is perpendicular to the floor during the squat.
4. Straighten your knees to lift the weight from the supports. Take a deep breath and slowly squat downward, taking about three to four seconds to reach the bottom position. Continue squatting until your knee angle is at 90 degrees of flexion.
5. After reaching the bottom, stand up but do not explode out of a position with an extremely bent knee since this can cause a serious injury. Starting slowly upward will help protect your knees in a vulnerable position. Accelerate the weight upward only after you are partway up.3
6. Don’t lock out your knees at the top position because the stress will be removed from your quadriceps and the bones of the hips and thigh will transmit the force downward without the need for muscle activation.
7. The next repetition is the same as the first, so that the body is lowered slowly into the squat position, but it is raised with a healthy thrust upwards.
8. Place the weight stack back on the supports at the end of your set.
If your feet are placed too close together when squatting (i.e., six inches apart) this will produce a dangerously acute knee angle at the lowest part of the squat, which only invites a knee injury.3 This is worsened if you drop too rapidly to the bottom part of the squat.4 The idea is to maximally work your thigh muscles, but to have mercy on your knee joints.
Machine front squats are great for hammering your thighs1, especially if you have had back injury5 and you cannot do heavy barbell squats. The machine provides stability and isolates the anterior thighs with minimal activation of the gluteus muscle groups as compared to barbell back squats.6 A few sets of this exercise and your anterior thighs and especially your vastus lateralis muscles will be screaming, yet after a few weeks, you will be piling the weight on the machine and asking for more.
While the machine version of front squats was not around when the first chapters of Joe Weider's impact on bodybuilder history books was written, the barbell version was. Machine front squats will help you etch grooves and deep valleys across your thighs. In honor of his Joe's contributions to bodybuilding, it is only fitting this week to grind out another two reps in the machine front squat as a memorial to the melting of the old-school bodybuilding history with the modern era of bodybuilding, which Joe helped to usher in.