Shoulder electromyography activity during push-up variations: a scoping review

Abstract

Background: Push-ups (PU) are a common closed chain exercise used to enhance shoulder girdle stability, with variations that alter the difficulty or target specific muscles. To appropriately select and prescribe PU exercises, an understanding of muscle activity during variations of the PU is needed. The purpose of this scoping review was to identify common PU variations and describe their muscle activation levels.

Methods: Databases searched included PubMed, CINAHL, Scopus, and SPORTDiscus for articles published between January 2000 and November 2019.

Results: Three hundred three articles were screened for eligibility with 30 articles included in the analysis. Six PU types and five muscles met the criteria for analysis. Weighted mean electromyography (EMG) amplitude was calculated for each muscle across PU types and for each PU type as a measure of global muscle activity. Triceps and pectoralis major had the highest EMG amplitude during unstable, suspension, incline with hands on a ball and the standard PU. Serratus anterior had the highest EMG amplitude during PU plus and incline PU. The greatest global EMG amplitude occurred during unstable surface PU.

Discussion: These results provide clinicians with a framework for prescribing PU to target specific muscles and scale exercise difficulty to facilitate rehabilitation outcomes.

Keywords: Push-up; electromyography; exercise; rehabilitation.

Figure 1.

Standard push-up and push-up plus. (a) Starting position for standard push-up from lateral view. (b) Starting position for push-up plus from lateral view. (c) Starting position for standard push-up demonstrating scapulae in neutral position. (d) Starting position for push-up plus demonstrating scapular protraction.

Figure 2.

Article search and selection flow diagram. EMG: electromyography; MVIC: maximum voluntary isometric contraction.

Figure 3.

Unstable, suspension, incline, incline on ball push-ups. (a) Unstable push-up on BOSU® ball. (b) Suspension push-up on TRX® with handles 10 cm from floor. (c) Incline push-up with hands elevated 65 cm. (d) Incline push-up on 65 cm ball.

Figure 4.

EMG amplitude across muscles and push-up type. Weighted mean EMG amplitude for each muscle group during identified push-up variations. Data are presented as weighted mean ± SE. EMG: electromyography; M/LT: middle/lower trapezius; MVIC: maximum voluntary isometric contraction; n: number of studies evaluated for each muscle; PM: pectoralis major; SA: serratus anterior; UT: upper trapezius.

Figure 5.

Global EMG amplitude for each push-up type. Combined weighted mean EMG amplitude of pectoralis major, serratus anterior, middle/lower trapezius, upper trapezius, and triceps for each push-up movement. Data are presented as weighted mean ± SE. EMG: electromyography; MVIC: maximum voluntary isometric contraction; n: number of studies evaluated per push-up movement; PU: push-up.