The comparison of muscle activation levels between a conventional bench press without and with the use of a bench press block

Abstract

Introduction. The bench press exercise is what most people use to measure their strength by. The sticking point in the bench press is a common area where failed attempts in the bench press exercise may occur. This is due to the lack of activation from one set of muscles to another. Many methods have been investigated to improve the bench press apart from the use of bench press blocks. A bench press block is placed on an individual’s chest performing the exercise to reduce the range of motion to train the activation of muscles through the sticking point. To the author’s knowledge, at present, no study has compared the muscle activation levels of a bench press without and with the use of a bench press block. This would enable the identification of which of the prime movers were most dominant at each phase of the bench press exercise. Methods. 12 undergraduate students (age, 20.4 ± 0.8years; mass, 85.5kg ± 7.9kg; height, 1.76m ± 0.05m) took part in the study. Average bench press experience was 3 years ± 1.1years. Each individual performed the bench press without the block followed by using the block at 90% of their 1RM (one repetition max) for one repetition only. All muscles investigated were collected using surface EMG (electromyography). All signals were normalised in Microsoft Excel (Microsoft, USA) using a rolling 25ms average. Results. The biceps brachii (BB), posterior deltoid (PD) and the tricep brachii (TB) all showed significant differences (p<0.05) with the greatest peak amplitudes being generated without the bench press block for the BB and PD (BB=1061.6mV ± 595.8; PD= 441.9mV ± 314.5). However, the TB generated the greatest peak amplitudes with the bench press block (TB= 2040.7mV ± 977.4). Conversely, the anterior deltoid (AD) and pectoralis major (PM) showed no significant differences (p>0.05) (AD= without block 2233.6mV ± 736, with block 2231.1mV ± 791.5; PM= without block 2277mV ± 1826.6, with block 192.5mV ± 179.6). Discussion. The AD and PM can be considered an agonist pair and are vitally important throughout the whole lift in the bench press exercise. The BB and PD are at their peak activation at the end of the eccentric phase without the use of the bench press block. At this point, they are both contracted concentrically as flexion is at its greatest. The peak activation of the TB was with the use of the bench press block. It was suggested that the dramatic change in the TB considering the PM remained constant was due to the fact that the TB has stabilization demands at both the elbow and the shoulder. Conclusion. In conclusion, the sticking point may be caused by the delay in activation of the TB and/or inability to sustain activation of the AD and PM. Therefore, isolation exercises to improve the activation of the TB and sustain activation of the AD and PM will be of interest to those coaches and athletes looking to improve bench press performance.