Why? The Science of Athletics

I r DIAGRAM AND DEDUCTIONAL CALCULATION 239 The long jumper's problem is much the same as that of the sprinter, since the discovery of the optimum stride length is of equal importance to both. But long jumpers and high jumpers alike must give particular attention to the study of the footprint history of the last three strides of the approach run ; for herein lies a fundamental secret of success. For the long jumper, the first of the last three strides should be normal, let us say 7ft. 3 ins., the second should be abnormal, about 7 ft. 6 ins., and the third stride, which is the take-off stride, should be sub– normal, say 7 ft. · ~~-_._,.r;oola;,T~~~~Jtr~=:::-l The highjumper makes the first part of the ap- FIG. 64 proach at a trot and puts his power into the last three strides, ending with a strong stamp of the heel of the foot from which he springs. Further than that, the footprints of the high jumper and pole vaulter at take-off and landing will give the initiated observer a very good mental picture of wh~t the athlete has been·doing in the air between his take-off and landing. For example, a coach isi told of a pole vaulter who can always clear 11-ft comfortably, but invariably fails at I I ft. 6 ins. The coach then examines photographs, or sketches, of the vaulter's footprints. He knows that the man is 6 ft. in height, let us say, and has established his vaulting hand-hold at 11 ft. 6 ins. Therefore he makes a little sketch, as shown in Fig. 64. Now a 7 ft. perpendicular dropped from the man's I I ft. 6 ins. grip on the pole tells the coach that the take-off