Exercise Bikes For A Heart-pounding Workout Exercising is not just about keeping you fit and building muscles, it is also about working up a sweat and losing weight. That's why many exercise machine manufacturers have made a killing with so many gyms popping up all over the country. One exercise machine that is very affordable, compact enough to fit in a moderately sized house, and delivers great fitness results is the exercise bike, otherwise known as the stationary bike.