But for young hockey players, much of the endurance training should be anaerobic intervals, which also elevate the comfort zone for competition and increase speed, power, skill, and explosiveness.
By training aerobically (long, slow distances) there is no improvement in speed, explosiveness, or power. Furthermore, training at an aerobic pace on the ice would establish a slow comfort zone which is more than just a habit. There are definite physiological consequences when one tries to compete at a faster pace than practice.
We tested a college men's hockey team before and after six weeks of dryland interval training designed to improve running speed and quickness, anaerobic power on hills, and explosive power using skating-specific squat jumps. The training included short sprint intervals (5-15 seconds work : 50-60 seconds rest) and longer intervals for anaerobic power and endurance (30:60 and 30:90). There was no aerobic distance training. Workouts lasted only 45 minutes in the first week and increased to 90 minutes by the sixth week.
Post-tests showed significant improvements in skating quickness even though none of the training was on-ice. There were also improvements in power, measured during two anaerobic bicycle tests (12-second sprint test improved 6.8%; 40-second all-out Wingate test improved 8.0%). But the greatest percentage improvements were apparent during a graded exercise test to measure changes in cardio-respiratory parameters normally associated with aerobic training. Total work done during the graded exercise test increased by 29%. This, of course, measures a combination of aerobic and anaerobic work.