Behind the Neck Presses have been wrongly accused of being bad for the shoulders. The reality is, if you have a shoulder problem, this exercise will let you know. It is a test or indicator of shoulder health and not necessarily the cause of shoulder problems or pain.
If you can perform one with no pain, no limited range of motion and an even left / right extension of the bar, you are good to go. Keep them in your program for about 3 weeks, then switch to another overhead movement. Cycle them in and out throughout the year. An increase in the behind the neck press will carry over to your bench press and other upper body strength movements.
Form:
Ideally, for maximum strength and size don't get into double digit reps. I like doing these as a primary mover at the beginning of an upper strength workout (A1) as a substitute for bench press or immediately after bench press (B1) in the 4 to 6 sets of 2 to 4 reps or as an assistance movement towards the end of an upper body workout in the 3 to 5 sets of 4 to 7 rep range.
Some addition notes to consider:
If these cause pain in the shoulder, best to get a practitioner to do some structural balance or muscle tests on your (ART, sports chiro, reputable strength trainer for example) and see what the root cause of the pain is. Because it is NOT because Behind the Neck Press is bad for you. A primary cause of shoulder pain is exactly the opposite - not enough overhead pressing in the program.
Press & Grow!

References: Charles Poliquin & Bill Starr
DE Coaching Team
Krista Schaus PICP CPT
Ontario CANADA
krista@definingedge.ca
Kate Kline PICP CFT
Arizona USA
kate@definingedge.ca
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