Increase your bench press max and protect your shoulders by achieving upper body structural balance. Optimally training the shoulder girdle and scapular retractors can help you overcome strength plateaus, and it helps you prevent injury from all the stress you put on your muscles and joints from training. Don’t let an imbalance in the trapezius, or a shoulder injury keep you from reaching your training potential!
A new study in the Journal of Strength and Conditioning Research provides some insight into how to protect the shoulders and achieve structural balance between the upper body muscles. The study used untrained women and measured electromyographic (EMG) muscle activity in the upper, middle, and lower trapezius, and the serratus anterior—all the muscles involved that move the scapula during a number of exercises at light and heavy loads.
Results of EMG showed that many common upper body exercises activated all of the muscles tested similarly, which could lead to over-recruitment of the upper trapezius that is commonly a contributor to forward head posture and scapular dysfunction. For example, a seated overhead press, prone flexion and prone abduction (often called “I’s” and “T’s” in personal training and used to treat anterior shoulder tilt) with a load of greater than 60 percent of the 1RM produced at least 60 percent muscle activation of the entire trapezius and serratus anterior.
Using these exercises to increase strength in the lower and middle traps and serratus anterior is problematic because of the simultaneous impact they have on the upper trap. If the upper trap is stronger or there is dysfunction in the shoulder, you need exercises that principally recruit the weaker muscles, but have a very low level of upper trap activity.
A better exercise selection for shoulder dysfunction or forward head posture would be an exercise that favors the lower traps or serratus anterior over the upper trap. For instance, during two exercises called the push-up plus (a push-up performed with the forearms flat on the ground in a typical plank position) and a press-up (performed seated on a bench in which a trainee lifts themselves off the bench in a similar motion to a dip, but without flexing the elbow joint), the serratus anterior was much more active than the upper trap. These and other remedial exercises should be used rather than the overhead press, prone abduction, or prone flexion.
Researchers suggest that the typically trained prone abduction and prone flexion (I’s and T’s) be avoided until the lower traps and serratus anterior are stronger. In addition, avoid overemphasizing the pectoralis major, upper traps, or deltoids so as not to compromise the shoulder cuff. To avoid such an imbalance, you want the rotator cuff muscles as measured by an special internal rotation exercise to be about 9.8 percent of what you can lift in the bench press. Also, I’ve found that to ensure balance between the regions of the trapezius, it is best to do a specific structural balance test called the “Trap 3” that is covered in PICP level 1.
Andersen, C., Zeris, M., et al. Scapular Muscle Activity from Selected Strengthening Exercises Performed at Low and High Intensities. Journal of Strength and Conditioning Research. 2012. 26(9), 2408-2416.