Do not use cortisone unless you really know what your doing and know your body. This will not only screw up your immune system but possible cause long term knee problems. If you like your knees and love cycling then stay far, far away from cortisone. Before a race test supplements like Super Test, Anabolic Matrix etc, will help keep your energy level boosted and keep your heart rate low. Give yourself a good dose of sublingual B-12 to get things rolling, and stay away from stuff like Tren or Clen because that stuff take your wind away. I am about to start running a cycle of GW and I ride 60-120 miles on the weekend with intervals and light lifting through the week. I will let you know what works for me. If you want to improve endurance the keys are low body fat to muscle = higher V02, eat things like a lot blueberries to help V02, cordyceps can be taken to improve oxygen management, train at altitude if you can and eat foods that help clear cortisol from the system. But really when your in the depths of a road race or crit, you need to tell your body to shut the hell up - keep the rpms high and suffer because you can always rest after the race. Practice intervals and sustaining intervals output because this will help you bridge serious gaps and also if your in the break it will help you stay away from the pack. Like Jens Voight says - tell your legs to "shut up."