If you ever wonder how much time is spent sprinting in a hockey game and where the energy comes from to sprint here are some numbers for you. 19% of a hockey game is spent in a high intensity heart rate zone. This 19% is when the hockey player is sprinting and deciding the course of a hockey game. During these sprints at least 50% of the energy being used is coming from glycogen stores in the player’s muscles. Glycogen is sugar stored in the muscles. Conclusion: hockey players need sugar stores in the muscles to have good energy stores for a hockey game.