The evolution of resistance training equipment and gyms created a paradox. On one hand, it has allowed us to move quickly and easily from one exercise to another. Machines eliminated the task of breaking the bar down after the exercise. However, excessive use of machines, especially for the lower body, robs the lifter of producing a base of structural mass and strength from which to refine for competitive purposes. Even if your only competition is a one-on-one Saturday pickup game of basketball, or softball on the weekends, squats can build your lower body power and strength that will translate into greater stability, a higher rebound and a little faster sprint.
The best strategy for improving your overall lower body and thigh power is to build your program around barbell squats. Squats add to the mass and strength of the anterior thigh muscles, but gluteal muscles, small hip muscles, lower and middle back, hamstrings and even the calves are all activated to some extent by squats. This does not mean you have to eliminate leg extensions and curls, but there is no better exercise than barbell squats to build all the lower body musculature at one time.
Structure and Function
Even though the squat involves many muscles, this article will focus on the gluteal and the anterior thigh muscles. The quadriceps femoris (“quads”) is a group of four muscles that cover the anterior and lateral parts of the femur bone of the thigh. The three vasti muscles take their origin at the femur. The vastus lateralis muscle is attached to the lateral part of the femur, the vastus medialis muscle to the medial part of the femur and the vastus intermedius muscle to the central, anterior part of the femur. As a result, the vastus lateralis muscle sits over the lateral (outer) part of the thigh, while the vastus medialis covers the medial (inner) part of the thigh. The vastus intermedius is located between, but deep to, the vastus lateralis and the vastus medialis muscles.
The fourth quadriceps muscle, the rectus femoris, begins on the hipbones at the iliac crest and above the socket where the head of the femur sits (acetabulum) in the hip. Its fibers run straight down from the hip to the knee. The tendon from the vastus lateralis muscle combines with the tendons from the other two vasti muscles and the tendon of the rectus femoris to form the quadriceps tendon. The quadriceps tendon attaches to the patella (kneecap) and continues inferiorly (towards the foot) from the patella, where it is called the patellar ligament. The patellar ligament inserts into the tibial tuberosity, a bumpy portion on the tibia bone of the lower leg. The three vasti and the rectus femoris muscles extend the leg at the knee. The rectus femoris is much weaker when the hip is flexed (e.g., seated position, such as doing leg extensions).
The gluteus maximus is a large and thick hip muscle that’s activated to greater extents in deeper squats than in squats that stop when the thighs are parallel to the floor. The gluteus maximus begins from the crest of the ilium of the hip, and the posterior surface of the sacrum. It inserts on the posterior side of the femur and on the iliotibial band of the fascia lata, a tough connective tissue band, running from the hip down the lateral side of the thigh to the knee. The fascia lata keeps the muscles on the lateral side of the thigh from bowing out when the muscles of the anterior thigh contract.
Barbell Squats to Parallel
1. Place an Olympic squat barbell on the supports in a power or squat rack. The bar should be about mid-chest when you’re facing it. Warm your knees up with lighter weights in the early sets and save the heavy stuff for the final three or four sets. Set the height of the lower safety bar of the rack about two inches lower than the bottom position of your squat.
2. You may find that the heavy barbell will be uncomfortable (or even painful) as it rests on your upper trapezius, and this will detract from your ability to concentrate on your quadriceps muscles. Most gyms will have a bar pad you can wrap around the middle sections of the bar before setting up for the squat. Alternatively, you can wrap the center of the bar with a towel, or place the towel across your upper trapezius so the bar rests on the towel. If you wrap the bar, be certain it will not loosen during your set.
3. Grip the bar firmly with a wide grip. Place your head under the bar and bend your knees slightly. Position the wrapped bar high across your shoulders and the upper trapezius muscles (but not on your neck).
4. Keep your head up and tighten your back. Place your feet about shoulder width apart. Lift the bar from its starting position on the rack, but do not jerk the bar. Extend (straighten) your knees. Make sure you have full control of the weight before moving into position.
5. Take one step backward, just enough to clear the upper rack supports, so you will not hit it during the exercise. Place your feet a little wider than shoulder width with your toes pointed slightly outward. Keep your head up and your back straight and tight, but maintain its natural curves. Again, make sure you are in control of the weight, not the reverse, before beginning the squat.
6. Control the weight as you slowly lower your buttocks toward the floor by allowing your knees to flex. Continue squatting downward until the tops of your thighs are parallel to the floor, or when your knee angle has reached 90 degrees. Do not go lower than this position.
7. The lowest safety bar on your squat rack should have been set so that it does not contact the barbell at the bottom of the squat. Nevertheless, it should be high enough to “catch” the bar without excessive knee flexion if, for some reason, you fail during the set. It’s best to have a spotter to help you on the heavy sets, but even a spotter can mess up. Therefore, it’s important to have properly positioned the lowest safety bar of your squat rack before beginning your set.
8. After you’ve reached the parallel position, stand up in a smooth fluid movement. Stop just short of fully locking out the knees, thereby maintaining the tension on the anterior thigh muscles. Keep your back tight and flat and your head up on the way up, as well as on the way down.
Important Training Tips
The gluteus maximus and all four quadriceps muscles are strongly activated during the ascent. The tension in the vasti muscles diminishes as you approach the top portion of the lift (as your knees straighten). Conversely, the rectus femoris is less active at the bottom (flexed knee and hip position), but it becomes activated when the hip and knee are being extended. The hamstring muscles can also be activated, particularly since they also act to extend the hip. The erector spinae muscles achieve a moderate isometric contraction during the lift to keep your back flat.
By keeping your head up when squatting, you will ensure that your back is straight and flat. Excessive forward flexion of the torso may allow you to lift a little more weight, but it is done using greater activation of the back extensors and gluteal muscles rather than your quadriceps. This also increases the risk of lower back injury.
The vastus lateralis muscle will be stretched and more strongly activated if your toes point inward during the squat. A wider foot placement with your toes pointed outward will increase the contractile activity of the vastus medialis along the medial side of the knee. The variation in foot stance will have no effect on the activation of rectus femoris and vastus intermedius muscles.
You must train with moderately heavy weights to get the most out of the exercise, but you must also feel the weight and concentrate on your quadriceps during the exercise. If you want to improve your power, try to push the weight upward as quickly as possible from the parallel position. However, you should always lower the weight slowly and under full control. Again, do not drop lower than a position that is parallel to the floor, unless you want to overemphasize the gluteal muscles, while placing the knees at a more unstable and potentially injurious position.
Proper execution of parallel squats is no easy task, and you must be prepared to sweat a bit with this exercise. Nevertheless, when squats to parallel are properly performed, you will be able to reap the benefits of more lower body mass, strength and power, and these results are well worth the effort that is required to achieve success.
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