What is better to do if you are a sprinter trying to get faster: long-distance running or bicycling?

I am a sprinter trying to get faster. But I am also in color guard. so i cant run cross country i havta work on my own time. I am wondering what is better for me to become faster: running long distance or bicycling, and how often should I do it? Please give me as much info as possible and/or sources, Thanks!|||You should do both. Bicycling will help your legs get faster turnover, and long distance running will give you endurance, which sprinters still need, especially for like the 400 and 200. They will both help build strength in your legs. I would suggest exercising maybe 4-6 days a week for half an hour a day. You could alternate days running and biking for the best results.