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Another popular type of squatting exercise is the split squat (“lunge”). In this type of squat, the legs are placed at approximately shoulder width, but one foot is out in front of the athlete and one is placed to the rear, as if a lifter has just completed the jerk portion of the clean and jerk. The athlete descends by bending the front leg until the knee is slightly forward of the toes. The shin of the front leg should be ten degrees past perpendicular to the floor. It is important to maintain an upright posture when doing so. As when squatting, co-activation of the hamstring serves to protect the knee joint during flexion, (22) which is very important as often a greater degree of flexion will occurring when performing the split squat.

Certain misinformed and so-called “personal trainers” will have people squat in a smith machine, which is, quite simply, an idea both hideous and destructive. This is often done under the misguided “squat this way until you are strong enough to perform a regular squat” premise. Even if one overlooks the obvious fact that it is better to learn to do something right than build bad habits from the start, there are numerous other factors to be considered. The smith machine stabilizes the bar for the lifter, which does not teach the skill of balancing the bar, balance being important to any athlete, as well as the fact that free weight squatting strengthens the synergists which goes a long way to preventing injuries. A chain is only as strong as its weakest link, and the smith machine leaves far too many weak links. To say nothing of the fact that free weights provide a greater transfer of functional strength than machines. (23)Furthermore, the bar moves straight up and down, and very few people squat in this manner, which means that the smith machine does not fit a lifters optimal strength curve. (24) The smith machine also requires that the lifter either squats with his torso much closer to vertical than would be done with a real squat, which mechanically decreases the involvement of both the spinal erectors and the hamstrings. While this would be fine if it was done by the lifters muscular control, when the smith machine does this it is disadvantageous to the lifter by virtue of decreasing the ability of the hamstrings to protect the knee joint. Another mistake made, aside from simply using it in the first place, is allow the knees to drift forward over the toes, the chance of which is increased by the smith machine. As was previously mentioned, this greatly increases the shearing force on the knees. This from a device touted by the ignorant as “safe.”

There is a great debate about the use of belts when squatting, some sources insist that you must wear one, while others state quite the opposite. It is worth noting that there are plusses and minuses to wearing one. Using a proper belt while squatting can serve to increase intra-abdominal pressure (IAP) which will serve to stabilize the spinal column, reducing compressive forces acting upon the spine and reducing back muscle forces. (25) However, muscle activity of the trunk appears to be significantly reduced when using a weight belt, which can lead to the muscles of the trunk receiving a less than optimal stimulus when using a belt. (26) Other proponents of belt use have shown that the use of a properly designed power belt may improve a lifter's explosive power by increasing the speed of the movement without compromising the joint range of motion or overall lifting technique. (27)

There are numerous methods of utilizing the squat in any athlete’s training program. While a variety of rep and set ranges are optimal for a bodybuilder who wishes to maximize hypertrophy, an athlete’s must carefully plan a training program to meet their goals. Even though squatting will lead to gains in size, strength, and jumping ability, the more specific the program, the greater the results. When an untrained subject begins lifting, numerous programs produce gains in practically all areas, but this changes rapidly, with limited progress being made unless something is altered. (28)

To utilize the squat to gain in size is both simple and complex. Individuals will respond to a variety of rep ranges in different manners based on fiber type, training history, biomechanics, injuries, etc. Bodybuilders, who are concerned exclusively with gains in size, should squat heavy, as fast-twitch muscle fibers have the greatest potential for hypertrophy. However, sarcoplasmic hypertrophy (growth of muscle tissue outside of the sarcoplasmic reticulum) will contribute to overall muscular size, and is obtained by training with lighter weights and higher reps. Rate of training is once again an individual decision, but as a general rule, the greater the volume of training, including time under tension (TUT) per workout, the longer one must wait before recovery is optimized, allowing supercompensation to take place. A word of caution about performing higher repetitions while squatting: As the set progresses, the degree of forward lean increases. While this is desirable to increase the stress on the hamstrings, it takes the emphasis off of the quadriceps, as well as increases the risk of injury. (29)