400m, the rate of work should be one to four seconds less than one-fourth the time required to run a 1600m. For swimming, training distances should be one-fourth those used for running.Not only is the work interval important to the ATP-PC systems and the anaerobic glycolysis but also the type, duration and intensity of the relief interval. Two important considerations for the relief interval are duration and type of activity during the relief interval. The recovery pulse rate after the work interval is a good indicator of whether the athlete is ready for the next set. The pulse rate should drop to at least 140 bpm between repetitions and 120 bpm between sets. Also, a work-relief ratio can be used to determine proper relief periods. For work intervals 800m and over, a 1:1 or 1:1.5 work-relief ratio beneficial. For work intervals 400m to 600m, a 1:2 ratio is used. For work intervals less than 400m, a 1:3 ratio is used. Because of these work-relief ratios pulse rates have to be taken less often and proper relief is still maintained. The type of relief interval is just as important as the type of work interval for replenishing the energy systems. A rest-relief program should be used when trying to modify the ATP-PC system, which predominates during short-term exercise. Rest-relief helps to replenish ATP-PC systems more quickly so intense exercise can be repeated again. When training to improve anaerobic glycolysis, work-relief intervals should be used between work intervals. Mild workouts can partially block complete ATP-PC restoration. Therefore, anaerobic glycolysis will have to provide more energy during work intervals, strengthening the system.Many studies have been done in the anaerobic interval area. Such studies include research done on female speed cyclists showing that work-relief help build up anaerobic glycolysis during races and improved times overall. Another study done on glycogen and pyruvate acid production...
