# Contribution of trunk swing to the performance of fixed-seat rowing

## TL;DR

This study shows that restricting trunk movement improves performance for para rowers with impaired trunk function but worsens it for others.

## Contribution

The study provides empirical evidence on how trunk swing restrictions affect performance in para rowing classifications.

## Key findings

- PR1 rowers performed better with restricted trunk swing, showing faster 500m times and higher trunk extension force.
- PR2 and non-eligible rowers performed worse with restricted trunk swing, showing slower times and lower stroke impulse.
- Trunk restriction had minimal impact on force production for PR1 rowers but significantly affected others.

## Abstract

This study aimed to test the contribution of trunk swing to the 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 the demonstration of impaired function of trunk swing.

PR1, PR2, and NE rowers participated. Rowing ergometers were used in two different fixed-seating conditions, resulting in either (1) restricted trunk swing or (2) unrestricted trunk swing during the rowing stroke. Participants performed maximal effort 500 m 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 a repeated-measures general linear model, including condition and group and an interaction between condition/group.

Only PR1 rowers generated greater trunk extension force during the restricted condition compared with the unrestricted trunk condition (P < 0.01). The restricted trunk swing condition resulted in a faster time to complete 500 m and minimal impact on force production for PR1 rowers. NE and PR2 rowers showed a significantly faster time to complete 500 m and greater stroke impulse (Ns) in the unrestricted compared with the restricted trunk swing condition (P < 0.01).

These results provide evidence-based reasoning for the classification of fixed-seat rowers. Contrary to PR2 and NE rowers, whose rowing performance was decreased due to trunk restriction, PR1 rowers' performance benefits from the trunk restriction.