Dead lift, deep squats can impact knees, back
Fitness Alternatives exist that will yield the same results with less chance of injury
Dear Colin: My son is in a high school weightlifting class. Hes been having a lot of pain in his knees and low back from doing dead lifts and deep squats, and has told his teacher. His teachers response is suck it up, because if he doesnt demonstrate perfect form with them by the end of class, hell fail. Are these lifts really that important, and if so, could they be damaging my sons joints? Darren D.
Your sons teacher is being in-sensitive to your sons needs and lacks basic knowledge in biomechanics. Theres not a single research article supporting the notion that the deep squat and dead lift are essential for physical greatness. In fact, theres research showing these lifts can be dangerous to perform relative to the knees and lumbar spine.
The dead lift is performed by lifting a weighted bar off the floor. The primary muscles used are the spinal extensors, glutes and thigh muscles. The problem with the dead lift is that even when done correctly, dangerous shear forces are imposed on the lumbar spine and knees because of the angle of trunk lean (close to 45 degrees relative to gravity) and knee bend (greater than 50 degrees). Consequently, consistent performance could cause a herniated disk and/or early onset arthritis.
The deep squat is similar to the dead lift mechanically, as it uses the glutes, spinal extensors and thigh muscles. Again, because of the excessive forward trunk lean coupled with bending the knees greater than 50 degrees, (theyre 110 degrees), the forces on the lumbar spine and knees are just too high. Note that even if the person doing the deep squat doesnt feel pain, this does not mean damage isnt being done.
There are other exercises that may be more effective than the dead lift or deep squat, but with substantially less risk. Doing the squat to 50 degrees of knee bend while maintaining a neutral spine adequately trains the thighs and glutes but without excessive knee and spine stress.
For anyone claiming this is too easy, you arent doing it right.
The bent-over row is a great substitute for the dead lift, training key back muscles far more effectively than the dead lift while still using the glutes and thighs. Personally, I wish I had learned this when I was in high school; I could have avoided a lumbar fracture.
Youve shed light on a major problem in American high schools: lack of adequate and standardized training of physical education teachers/coaches to protect our children from dangerous advice. Physical education teachers/coaches should be required to pass a standardized course in applied biomechanics before teaching exercise to kids, possibly preventing unnecessary injuries that have lifelong consequences. And having a lot of personal experience in lifting does not make one an expert in resistance training. Thats like saying, Ive been driving for 20 years, so Im an expert car mechanic.
Show this to your sons teacher. If his light doesnt go on, tell him youll take the issue up with the principal. If you need a scientific voice, let me know.
Colin Hoobler is a licensed physical therapist, hosts a live health segment on KGW Channel 8 and has written two books on exercise as treatment for disease and injury