Hydrodynamics and electromyography: ergonomics aspects in aquatics.

In a quadruple approach we have suggested the ergonomics links between fundamental hydrodynamics, applied dynamics of swimming, electromyographical aspects and specific training. Fundamental and applied hydrodynamics were investigated in a Dutch Marine Ship model test station allowing for the measurement of passive drag in different positions and of active (swimming) drag. It was found that drag in a prone position under the water surface was greater than at the water surface, but active drag while swimming reached twice the drag values of any passive drag condition. This indicates that body form has no influence on drag and propulsion. Since it is merely the technical execution of the swimming movement that will influence performance, telemetric EMG of the involved musculature has allowed a complete kinesiological picture of the front crawl movements to be made. This knowledge is basic for the study of specific and alternative training systems, such as specific dry land training.