Muscle action and stress on the ribs in rowing

• Published in: Physical therapy in sport 2000-08, Vol.1 (3), p.75-84
• Main Authors: Wajswelner, Henry, Bennell, Kim, Story, Ian, McKeenan, Joan
• Format: Article
• Language: English
• ISSN: 1466-853X; 1873-1600
• DOI: 10.1054/ptsp.2000.0023

Objective: chest muscle action has been proposed as a cause of rib stress fractures in rowers. The objective was to examine the sequence of peak chest muscle electromyography (EMG) activity and ribcage compression during the rowing stroke. Design: a within-groups, repeated measures design was used. Subjects and Setting: seventy-four rowers (34 male, 40 female) from elite, club and school levels of competition were tested at the Australian Institute of Sport in Canberra or the School of Physiotherapy at the University of Melbourne. Method: surface EMG was used to measure timing of peak activity of serratus anterior (SA) and obliquus externis abdominis (OEA). An extensometer indicated the time of maximal ribcage compression (RC). Subjects used a rowing ergometer and the sequence of these events was examined. Results: SA peak activity occurred just before the catch while OEA peak activity occurred at the finish of the stroke. RC followed OEA closely, and was not coincident with peak SA activity. Results were consistent across the levels of rowing experience. Conclusion: a consistent sequence of peak muscle activity and RC was found, with RC following OEA activity closely. This indicates that the ribs may undergo compressive stressing via OEA activity rather than SA activity in rowing.