Maximal Fully Tethered Swim Performance in Para Swimmers With Physical Impairment

The assessment of swimming propulsion should be a cornerstone of Paralympic swimming classification. However, current methods do not objectively account for this component.

To evaluate the swimming propulsion of swimmers with and without physical impairment using a 30-second maximal fully tethered freestyle swim test.

Tethered forces were recorded during maximal fully tethered swimming in 80 competitive swimmers with (n = 70) and without (n = 10) physical impairment. The relationships between absolute and normalized tether forces and maximal freestyle swim speed were established using general additive models.

Para swimmers with physical impairment had lower absolute and normalized tether forces than able-bodied swimmers, and there were moderate positive correlations found between tether forces and sport class (τ = .52-.55, P < .001). There was a nonlinear relationship between tether force and maximal freestyle swim speed in the participant cohort (adjusted R2 = .78-.80, P < .001). Para swimmers with limb deficiency showed stronger relationships between tether force and maximal freestyle swim speed (adjusted R2 = .78-.82, P < .001) than did Para swimmers with hypertonia (adjusted R2 = .54-.73, P < .001) and impaired muscle power (adjusted R2 = .61-.70, P < .001).

Physical impairments affect Para swimmers' tether forces during maximal fully tethered freestyle swimming, explaining a significant proportion of their activity limitation. It is recommended that maximal fully tethered swimming be included in Paralympic swimming classification as an objective assessment of swimming propulsion.