Squatting is a primitive pattern; it is one we learn before we even stand. A deep squat gets us to that piece of furniture that allows us to grab and move to standing as a toddler. This pattern is often lost with injury and life style and once you hit a certain age it is often warned against. Are body was made to squat low this is evident in any Geographic National magazine where a 70 year old lady is in a full squat with a pot on her head. How can this be if we should not squat past 90 degrees once we hit 40? The issue is two fold; one the lady never lost her patterning and two she never got sacked in the back field. Past medical histories of injury and loss of function have caused this blanket statement about the dangers of deep squatting. If you do not have an injury that has warranted surgery or could in the future you should be able to squat low. This low squat should have your butt on your calves with your feet flat, and this should be with your body weight. The argument does get complicated when you add strength training on top of this, and this is where the controversy gets its genesis. Weighted deep squats effect people different, if you have the pattern down but you have long thigh bones like an NBA center you will have some issues. This is where you have to monitor for joint pain post workout. Muscles soreness is acceptable but joint pain means it is not for you. A good recommendation would be to maintain a body weight low squat and a 90 degrees weighted squat if you have issues or concerns. A leader in the field of rehab and strength, Gray Cook, has a motto: “maintain the squat and train the deadlift”. I think it is sounds advice to concerned or injured people.