Ever since Bondarchuk published the English translation of his two-volume work several years ago, “transfer of training” has become a buzz word in the physical preparation community. The concept itself is quite simple: exercises are of varying usefulness depending on how much the gains in one exercise transfer to the gains in the competitive exercise. We want to use the exercises with a positive transfer, i.e. exercises that will help us throw further as we improve in them. Exercises that have no effect on the throwing, or that hurt results, have either a neutral or negative transfer of training.
The best way we have to measure the amount of transfer comes from correlations. But correlations just show if two exercises rise and fall together; they do not show the actual casual link between the two exercises or which direction it flows. For example, let’s say that a thrower sees a simultaneous increase in hammer throw results and front squat performance. We all would likely infer that front squats are improving the throw. But it could also be the opposite: the throw might be helping the squat. I call this a reverse transfer of training. The transfer of training effect operates the same no matter what direction it is going, but in these cases the direction is simply the opposite of what was intended.