Background: Although rehabilitation exercises are recommended in the nonoperative and postoperative treatment of biceps-related disorders and superior labrum anterior-posterior (SLAP) lesions in overhead athletes, a progressive exercise protocol with controlled low to moderate loads on the biceps has not yet been described.
Purpose: To describe a continuum of exercises with progressive low to moderate loads on the biceps based on electromyographic (EMG) analysis.
Study design: Descriptive laboratory study.
Methods: Using surface electromyography, the EMG activity of 8 muscles (upper [UT], middle [MT], and lower [LT] trapezius; serratus anterior [SA]; anterior [AD] and posterior [PD] portions of the deltoid; and biceps [BB] and triceps [TB] brachii) was measured in 32 healthy participants performing 16 commonly described shoulder rehabilitation exercises.
Results: Of the 16 exercises, 13 (side-lying shoulder forward flexion, prone extension, seated rowing, serratus punch, knee push-up plus, internal and external rotation both in 20° and 90° of abduction, forearm supination, uppercut, and internal and external rotation diagonal) showed low (<20% maximal voluntary isometric contraction [MVIC]) EMG activity in the BB, and 3 (forward flexion in supination, full can, and elbow flexion in forearm supination) showed moderate (20%-50% MVIC) activity. None of the exercises elicited high (>50% MVIC) EMG activity. Based on the results, a ranking was calculated of the exercises, with mean EMG levels between 2.2% ± 1.24% (during internal rotation against resistance in 90° of shoulder abduction) and 35.9% ± 18.82% (during forward flexion in external rotation and supination) of MVIC.
Conclusion: This study describes a continuum of exercises with an increasing level of EMG activity in the BB. Exercises targeting the trapezius resulted in less loads on the biceps compared with exercises for the SA. In addition, exercises with an internal rotation component showed low activity in the BB. In general, the exercises meant to target the BB showed the highest levels of activity in the BB.
Clinical relevance: These results may assist the clinician in the appropriate choice of exercises in a graded rehabilitation program of biceps-related injuries.
Keywords: SLAP lesions; biceps pathological disorders; electromyography; rehabilitation.
© 2014 The Author(s).