Polish Your Technique
There's nothing more frustrating than making the same mistake, over and over again. Dismounts and mounts are where cyclo-crossers make their most energy-sapping errors, so drill yourself in these key techniques until they become second nature (you may even find yourself mounting your road and mountain bikes in cyclo-cross style, as former national champ Laurence Malone does).
Run Early and Often
You may be able to ride for days, but don't think that fitness and muscular strength will carry over into running, which makes an entirely different set of demands on your body. Do some easy running on hills, walking or jogging the descents, beginning about a month before your first cyclo-cross race. Road and mountain bike racers alike will experience some muscle soreness when making the transition from riding to running; it should go away within three weeks.
Use Good Off-Road Shoes
Don't settle for running shoes; your road cycling shoes won't do either. The first has a sole that's too soft for efficient pedaling, and the second has a sole that's too inflexible for comfortable running. A mountain-bike shoe with a flexible toe section and stiff heel can handle both.
Ride a Bike You Like
Use the same kind of bike you use in your regular season - mountain bikes for mountain-bikers 'cross bikes or road bikes modified for off-road use for roadies. This will address the specifics of your sport.
Train Hard and Short
Do high-intensity workouts - anaerobic-threshold work and anaerobic intervals are very important. Be sure to include adequate recovery for your races. Remember: A cyclo-cross race is no longer than an hour or so, so those three- to six-hour training rides aren't necessary.
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