Take the 2-minute tour ×
Physical Fitness Stack Exchange is a question and answer site for physical fitness professionals, athletes, trainers, and those providing health-related needs. It's 100% free, no registration required.

When bench pressing, at max extension, should I lock my elbows or keep them loose? What about my knees when squatting?

UPDATE: Here are some links from the Mayo Clinic warning against locking joints while lifting:
http://www.mayoclinic.com/health/weight-training/SM00041&slide=6
http://www.mayoclinic.com/health/weight-training/sm00041&slide=2

2nd UPDATE: Also, must admit, a major concern of mine is that in military, always told us "Don't lock your knees, you'll pass out". This is when standing at inspection.

share|improve this question
    
It's entirely possible that locking your knees could cause you to pass out in inspection. That has little or no connection to fully extending your limbs when lifting. –  Dave Liepmann May 9 '12 at 13:44
    
As for the Mayo clinic, they give no reasons and so their only argument is pure assertion. If they gave reasons we could disagree, but as is we can simply give our reasons and note that their exercises are much more oriented towards rehabilitation than actual strength training. –  Dave Liepmann May 9 '12 at 13:49
    
About locking knees during inspection, that's for like 10s of minutes at a time. During a lift, it will be for less than a second as you grab a breath for the next rep. –  user3085 May 9 '12 at 17:52
1  
Regarding the mayo links, they refer to the leg extension, an exercise that places much more stress on the ACL than a squat. When the knee is locked in extension during leg extensions, the skeleton is not able to help you support the weight. This is not the case in the squat. Regarding the chest press, the form they describe is completely different than the bench press (feet up on the bench, back not arched, scapulas not retracted, not bringing elbows below bench surface); I don't think their advice about elbow position at lock-out is any more reliable. –  user3085 May 9 '12 at 17:59

3 Answers 3

up vote 5 down vote accepted

Yes, you should lock your elbows at full extension for each completion of a bench press repetition and also the knees at the top of the squat.

This is supported by text from Starting Strength, 3rd Edition:

Regarding the bench: "...push up on the bar, locking out your elbows."

"At the top [of the squat], all the skeletal components that support the bar - the knees, hips, and spine - will be locked in extension so that the muscular components have to exert only enough force to maintain this position."

I will speculate as to some reasons for this:

  • allows you to release your valsalva maneuver and take a breath of air while the weight is supported by skeletal components
  • allows you to train through the full range of motion
share|improve this answer

The only reason not to do the full range of motion is if you're cheating in order to get more reps or use more weight than you could with proper form. Repetitively shorting weightlifting movements can cause joint problems.

Move your body through the whole movement. There's no good reason not to.

Further, what happens if you don't extend your joints fully? Use it or lose it--your body will stop being capable of going to full extension. Then you'll have to start shorting the movement more and more over time, until you are decrepit and immobile.

share|improve this answer
    
Isn't locking joints harmful? I remember always being told not to do that, and I believe the Mayo Clinic also advises against it (I believe). –  S. Robert James May 7 '12 at 15:35
    
@S.RobertJames I'd be surprised if the Mayo Clinic believes that extending your arm fully is harmful. Hyperextending the arm, sure, that's no bueno, but nobody's espousing that. Without an actual claim that lifting weights through the whole ROM is bad, we can't disagree more substantively than that. –  Dave Liepmann May 7 '12 at 15:50
    
Added links from Mayo Clinic warning not to lock –  S. Robert James May 9 '12 at 7:55

I don't think there is an issue with locking our elbows(at a safe speed obviously) but in lifting, locking the knees is usually a no-no, especially with things like power (olympic) lifts.

share|improve this answer
    
Why? Do you mean when receiving the bar, or when completing the lift? –  Dave Liepmann May 9 '12 at 16:01

Your Answer

 
discard

By posting your answer, you agree to the privacy policy and terms of service.

Not the answer you're looking for? Browse other questions tagged or ask your own question.