During pushups, locking the elbows may give you a brief rest, but it also takes the stress off your muscles and puts it on your elbow joints. You can avoid this by, first, keeping a very slight bend in the elbows at the top of the movement. Second, keep the pushups slow, controlled and flowing from one rep to the next. If you're too fatigued to avoid locking the elbows, take a break or try an easier modification.
Other Common Pushup Mistakes
Aside from the more common form mistakes, there are a few other things to watch out for:
- Faulty hand position: There are a number of ways to position the hands during pushups; normal grip, wide grip, narrow grip, staggered grip, etc. One common mistake, however, is placing the hands too far forward, which may stress the shoulders. Whatever grip you choose, make sure your hands are positioned at the same level as the shoulders and chest rather than under the neck or chin.
- Lowering halfway down: If you find a pushup difficult, one common response is to avoid going all the way down. Changing your range of motion at times can be a positive thing but, if all of your pushups involve only half of the movement, move to an easier version that allows you to go all the way down and all the way back up.
- Rolling on the ball: When doing pushups with the lower body propped on a ball, it's easy to let the ball roll forward or back to 'help' you during your pushup. Use your core and legs to brace your body on the ball so that, as you move up and down, the ball doesn't move.
- All of the above: When fatigue is high, you may find your body failing in multiple areas -- sagging torso, dropped head, locking elbows and stopping the movement halfway down. Remember that stopping early, or switching to an easier version, is better than continuing with bad form.
American Council on Exercise. (2003). ACE Personal Trainer Manual, 3rd Edition. San Diego, CA: American Council on Exercise.
American College of Sports Medicine. (2006). ACSM's Guidelines for Exercise Testing and Prescription. Baltimore, MD: Lippincott Williams & Wilkins.
Cogley RM, Archambault TA, Fibeger JF, et al. Comparison of muscle activation using various hand positions during the push-up exercise. J Strength Cond Res. 2005 Aug;19(3):628-33.