Using an indoor bikes can provide just as much exercise as your outdoor bike.
Choosing Your Bike
Upright vs Recumbent
The big difference between these two spinning bike, is more like riding an actual bicycle. The main advantage is that you can stand up to give you more power when pedaling against inclines.
Resistance
Good resistance is key to having a better workout. There are three types of resistance you can find in a bike. Direct tension means you are manually adjusting the resistance you feel when you pedal. magnetic. Magnetic currents provide the best and most quiet workout.
Features
Having loads of cool features is always nice, but consider whether or not you're actually going to use them. One feature they ''should'' all come with is a compact model.