A trainer is a device that allows you to use your standard road or mountain bike indoors and get a good workout while staying warm and dry during those dark days of winter. It's also a great tool for warming up before a race.

A trainer works by clamping the rear wheel with skewers holding the bike off the ground. A drum presses against the rear wheel to provide resistance while you pedal, just as the road and wind do when you ride outdoors. The front wheel is generally propped up to the same level as the rear using a block of wood, a phone book, or the Front Wheel Riser Block that we sell. You can also adjust the front wheel height higher to simulate riding uphill to stress slightly different muscles.

There are a variety of trainers available. The biggest difference between them is the form of resistance that is used, and how this resistance changes with effort.

• Wind Trainers - these are generally the least expensive and use a fan (usually an enclosed turbine fan) to provide resistance. These tend to be a bit noisy and provide less resistance than other types, so they are not as suitable to stronger riders.
• Magnetic Trainers - these trainers use two sets of magnets to create an opposing force which provides the resistance. Some of these trainers can vary the resistance by adjusting the spacing of the magnets, but this is generally not necessary since resistance can be varied by changing gears on the bike. Magnetic trainers can provide high resistance and the better models are reasonably quiet, but the progression of resistance with wheel speed is not quite as smooth as with a good fluid trainer.
• Fluid Trainers - these trainers use a fan inside a compressed hydraulic fluid to create resistance. Since the fan is immersed in fluid, very little noise is generated from the resistance element itself, although there is still plenty of noise from the the tire, wheel and drive train. Fluid trainers provide very smooth progression of resistance and can provide high resistance to satisfy strong riders. These devices are generally more expensive than other types, but they also deliver the most satisfying training.
• Rollers - another kind of indoor training device is called a set of rollers. Rollers are comprised of three tubes which rotate on bearings and are mounted in a bracket so the rear tire sits between two of the tubes and the front tire sits on the third tube. One of the rear tire tubes is connected to the front tire tube with a belt, so when the front tire spins with the rear tire. The cyclist actually rides the bike on the rollers, using weight and handlebar position to balance the bike in the center of the rollers. This requires a fair amount of skill and concentration, so rollers are not recommend for the beginner. On the other hand, they do help develop balance skills and many users find them much more fun than using a conventional trainer.