Figure 4. Scale to assess between-efforts recovery (left) and change of direction (right) abilities during high-intensity intermittent runs, derived from between-tests differences in maximal running speed (V). 30-15 : original 30-15, 30-15 : modified version of the 30-15 without resting period, 30-15 : modified version of the 30-15 without changes of direction. See methods for thresholds calculations.