The sticking region is the result of a poor mechanical force position.
The bench press is one of the most frequently used exercises among upper body, multi-joint training exercises. Prime movers for the bench press exercise include pectoralis major, anterior deltoid, and triceps brachii muscles. Due to the multi-joint nature of this exercise, where movement occurs simultaneously at the shoulder and elbow joints, the muscle groups can be strengthened simultaneously. Single-joint exercises such as the flat dumbbell fly or triceps extension, this is where movement occurs only at the shoulder or elbow joint. This strengthens only one or two muscle groups acting around these individual joints.
Tillaar (2013) compared the kinematics and muscle activation patterns of regular free-weight bench press (counter movement) with pure concentric lifts in the ascending phase of a successful one repetition maximum (1-RM) attempt in the bench press. The aim was to evaluate if diminishing potentiation could be the cause of the sticking region. Since diminishing potentiation cannot occur in pure concentric lifts, the occurrence of a sticking region in this type of muscle actions would support the hypothesis that the sticking region is due to a poor mechanical position. Eleven male participants (age 21.9 yrs, body mass 80.7 kg, body height 1.79 m) conducted 1-RM lifts in counter movement and in pure concentric bench presses in which kinematics and EMG activity were measured. In both conditions, a sticking region occurred. However, the start of the sticking region was different between the two bench presses. In addition, in four of six muscles, the muscle activity was higher in the counter movement bench press compared to the concentric one. Considering the findings of the muscle activity of six muscles during the maximal lifts it was concluded that the diminishing effect of force potentiation, which occurs in the counter movement bench press, in combination with delayed muscle activation unlikely explains the existence of the sticking region in a 1-RM bench press. Most likely, the sticking region is the result of a poor mechanical force position.
In this study, the kinematics and muscle activity of six muscles in the ascending part of the 1-RM bench press between counter movement bench press and a pure concentric bench press were examined. In both bench exercises a sticking region occurred. The start of the sticking region was different between the two conditions. In addition in four of the six muscles, the muscle activity was higher in the countermovement bench press compared to the concentric one. The total impulse was the same for the two bench presses. Together with the findings on muscle activity it was concluded that the diminishing effect of force potentiation, that occurs in CM bench presses, and delayed muscle activation unlikely explains the existence of the sticking region in a 1-RM bench press (Tillaar 2013). Most likely, the sticking region is the cause of a poor mechanical force position. Future studies in 1-RM bench press should investigate this poor mechanical force production region by means of leverage changes during this region.
The results of this study can help trainers and athletes in learning about sticking points and limitations of the muscles during pure concentric and counter movement bench pressing. It could be recommended that training should target the sticking region: 3–16 cm vertically from the sternum during the lift (also in pure concentric lifts). This may help in increasing bench press performance since the sticking region is the weakest region during the lift.
van den Tillaar R, Ettema G. A comparison of muscle activity in concentric and counter movement maximum bench press. J Hum Kinet. 2013 Oct 8;38:63-71.