Submitted By: Miles Forsyth, Auckland, New Zealand

I’m a competitive swimmer. I would like to do weight training but am concerned what effect it may have on swimming performance.

A very muscular, extremely lean person will probably never win Olympic gold in swimming because of buoyancy and hydrodynamics. The higher the muscle mass to fat mass ratio and the heavier the bones, the more energy must be expended to stay afloat (in addition to the energy required to propel the body forward). The energy expended to move forward through water is greater too for one with a bulkier, less streamlined body. Weight training added to swim training is unlikely to enhance and may hamper swimming performance. If the time and energy devoted to weight training takes away from the time and energy spent swim training then, based on the principle of specificity of exercise adaptations, weight training would be 100% likely to diminish swim performance. My advice: wait until you retire from competition, then hit the weights.