Inter-Limb Symmetry at Simultaneous and Alternated Arms Flexion by the Elbow during Water Fitness Sessions

The aim was to compare the inter-limb symmetry between alternated and simultaneous arms flexion during water fitness sessions. Twenty-three elderly women were recruited to perform flexion by the elbow with different mechanical strategies: (a) simultaneous and (b) alternated. An incremental protocol was used, with four music cadences, starting at 105 beats per minute up to 150. The peak force of dominant and non-dominant upper-limbs was retrieved. A symmetry index (SI, %) was also used to quantify coordination. There were significant variations in force produced by the dominant and non-dominant limbs in most of the cadences in the alternated or simultaneous actions. Differences with a medium effect between upper-limbs were shown when moving simultaneously indicating that an alternated movement can be a more proper strategy to work with. Despite that, both strategies seemed to be characterized by an asymmetric pattern (SI from 20 to 30%), requiring full attention from water fitness practitioners.