Muscle Activity Ratios of Scapular Stabilizers During Closed Kinetic Chain Exercises in Healthy Shoulders: A Systematic Review

Abstract

Context: Selective strengthening of scapular stabilizers is one of the emphases of the recent literature. Closed kinetic chain (CKC) exercises are used extensively in shoulder rehabilitation. However, a limited number of studies have reported scapular muscle ratios during CKC exercises. Objectives: To determine the CKC exercises producing the optimal ratios of the scapular stabilizer muscles in healthy shoulders. Evidence Acquisition: A systematic search within PubMed, Embase, CINAHL Plus, and SPORTDiscus with Full Text and ULAKBIM National Medical Database was performed up to January 2018. Studies were selected according to the predetermined criteria. If the pooled mean ratios (upper trapezius [UT]/middle trapezius [MT], UT/lower trapezius [LT], and UT/serratus anterior [SA]), which were calculated from the percentage of maximum voluntary contractions of muscles, were <0.60, these exercises were considered as ideal for higher activation of the MT, LT, and SA than the UT. Evidence Synthesis: The search identified 1284 studies, and 29 observational studies were included for review. Seventy-nine CKC exercises were determined. Four exercises for the MT, 9 for the LT, and 59 for the SA were identified from the articles as being optimal exercises to activate the specified muscle more than the UT. Conclusions: This review identified optimal CKC exercises that provide good ratios between the MT, LT, and SA with the UT. Most exercises have optimal UT/SA ratios, but some exercises performed on unstable surfaces may lead to excessive activation of the UT relative to the SA. For the UT/MT, the isometric low row, inferior glide, and half supine pull-up with slings are the ideal exercises. Isometric one-hand knee push-up variations seem to be the best choice for the UT/LT. The results suggest that many CKC exercises may be utilized to enhance scapular muscle balance when rehabilitating shoulder pathology.

Electromyographic analysis of the serratus anterior and upper trapezius in closed kinetic chain exercises performed on different unstable support surfaces: a systematic review and meta-analysis

“… Notes. UT upper trapezius SA serratus anterior ES effect size CI confidence interval ↓ Downgraded by one level a Assessed with a standardized quality assessment form for observational studies ( Siegfried et al, 2005 ) and it was adapted specifically for this study following recommendations of previous reports regarding risk of bias assessment of EMG studies ( Ganderton & Pizzari, 2013 ; Edwards et al, 2017 ; Karabay, Emük & Özer Kaya, 2020 ; Cappato de Araújo et al, 2021 ). b Assessed with Egger’s test ( p < 0.05, risk of publication bias).…”

“… a Assessed with a standardized quality assessment form for observational studies ( Siegfried et al, 2005 ) and it was adapted specifically for this study following recommendations of previous reports regarding risk of bias assessment of EMG studies ( Ganderton & Pizzari, 2013 ; Edwards et al, 2017 ; Karabay, Emük & Özer Kaya, 2020 ; Cappato de Araújo et al, 2021 ). …”

“…Two independent authors (OC and MV) assessed the risk of bias of all included papers using a standardized quality assessment form for observational and descriptive studies ( Siegfried et al, 2005 ) and it was adapted specifically for this study following recommendations of previous reports regarding risk of bias assessment of EMG studies ( Table 2 ) ( Ganderton & Pizzari, 2013 ; Edwards et al, 2017 ; Karabay, Emük & Özer Kaya, 2020 ; Cappato de Araújo et al, 2021 ). The Non-Randomized Studies Methods Group of The Cochrane Collaboration has commended the quality assessment tool ( Reeves et al, 2021 ).…”

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

“…This is consistent with a systematic review in which all unstable pushing exercises had high UT to SA activity ratios. 54 As many individuals with shoulder pathology demonstrate increased UT activity and SA weakness or underactivity during arm elevation, unstable PU are not the preferred PU variation. The standard PU or PU plus, as noted below, may be more appropriate due to their low UT and high SA activity.…”

Method of Measuring Pull-up Times Based on Built-in Acceleration Sensor in Mobile Terminal

“…In terms of movement details, It must include an upward acceleration process and an upward deceleration process. The former corresponds to upward acceleration, that is, the human body is in an overweight state, and the resultant force generated by the arm will be greater than gravity [15][16][17]. The latter is that the human body rises to a certain stage, and it will inevitably be a process of deceleration and rise.…”