Although the squat has long been a basic element of weight training, it has not been without controversy over its safety.
Some trainers claim that squats are associated with injuries to the lumbar spine and knees. Others, however, continue to advocate the squat as one of the best exercises for building muscle and strength. Some coaches maintain that incomplete squats (those terminating above parallel) are both less effective and more likely to cause injury than a full squat (terminating with hips at or below knee level).
A 2013 review concluded that deep squats performed with proper technique do not lead to increased rates of degenerative knee injuries and are an effective exercise. The same review also concluded that shallower squats may lead to degeneration in the lumbar spine and knees in the long-term.
Squats used in physical therapy
Squats can be used for some rehabilitative activities because they hone stability without excessive compression on the tibiofemoral joint and anterior cruciate ligament.
Deeper squats are associated with higher compressive loads on patellofemoral joint and it is possible that people who suffer from pain in this joint cannot squat at increased depths. For some knee rehabilitation activities, patients might feel more comfortable with knee flexion between 0 and 50 degrees because it places less force compared to deeper depths. Another study shows that decline squats at angles higher than 16 degrees may not be beneficial for the knee and fails to decrease calf tension. Other studies have indicated that the best squat to hone quadriceps, without inflaming the patellofemoral joint, occurs between 0 and 50 degrees.
Combining single-limb squats and decline angles have been used to rehabilitate knee extensors. Conducting squats at a declined angle allows the knee to flex despite possible pain or lack of mobilization in the ankle. If therapists are looking to focus on the knee during squats, one study shows that doing single-limb squats at a 16-degree decline angle has the greatest activation of the knee extensors without placing excessive pressure on the ankles. This same study also found that a 24-degree decline angle can be used to strengthen ankles and knee extensors.
Different Sets For Squats
Forced repetitions are used when training until failure. They are completed by completing an additional 2-4 reps (assisted) at the end of the set. Partial repetitions are also used in order to maintain a constant period of tension in order to promote hypertrophy. Lastly, drop-sets are an intense workout done in at the end of a set which runs until failure and continues with a lower weight without rest.