Contribution of trunk swing to performance of fixed-seat rowing

Renee Lafreniere¹Matt Jensen²Tomislav Smoljanovic³James M Wakeling⁴Marc Klimstra⁵Rebecca Thomas Orr⁶Courtney Pollock^1*

• ¹University of British Columbia, Vancouver, Canada
• ²Canadian Sport Institute Pacific, Victoria, British Columbia, Canada
• ³Department of Orthopaedics, University Hospital Center Zagreb, School of Medicine, University of Zagreb, Zagreb, Croatia
• ⁴Simon Fraser University, Burnaby, British Columbia, Canada
• ⁵University of Victoria, Victoria, British Columbia, Canada
• ⁶World Rowing, Lausanne, Switzerland

Introduction: To test contribution of trunk swing to performance during fixed-seat rowing in eligible and non-eligible (NE) para rowers. Assessment of trunk swing is used to classify para rowers with physical disability in Para Rowing (PR) 1 and PR2 rowers. PR1 rowers are classified based on demonstration of impaired function of trunk swing. Methods: PR1, PR2 and NE rowers participated. Rowing ergometers were used in 2 different fixed-seating conditions resulting in either: 1) restricted trunk swing or, 2) unrestricted trunk swing during the rowing stroke. Participants performed maximal effort 500m pieces (race-pace) in each seating configuration. Force production at the handle and fixed-seat rowing-specific trunk extension force was measured. Rowing performance measures were compared using repeated measures General Linear Model including condition and group and an interaction between condition/group. Results: Only PR1 rowers generated greater trunk extension force during the restricted condition compared to the unrestricted trunk condition (P<0.01). The restricted trunk swing condition resulted in faster time to complete 500m and minimal impact on force production for PR1 rowers. NE and PR2 rowers showed significantly faster time to complete 500m and greater stroke impulse (Ns) in the unrestricted compared to the restricted trunk swing condition (P<0.01). Discussion: These results provide evidence-based reasoning for classification of fixed-seat rowers. Contrary to PR2 and NE rowers whom restriction of the trunk decrease rowing performance, PR1 rowers' performance benefits the trunk restriction.