Of all the myths surrounding the Spinning® program, this one may be the biggest, no pun intended. Whether your motivation is weight loss, cross-training or overall fitness, it’s likely your goal is not to get any bigger—leave that to the guys in the weight room.

You already knowwhat makes you leaner: a healthy diet, regular exercise and strength training. A 40-minute Spinning® class burns an average of 400-500 calories, which is a good place to start.

But does climbing hills on a Spinner® bike make you bigger? If you answered “yes,” you’re definitely not alone. Maybe you’ve started taking classes and notice your clothes are fitting differently. The most likely reason: You’re working for new muscle groups, building new muscle and losing body fat. Remember, muscle is denser than fat, so it weighs more—it also burns more calories than its counterpart, which is good news if you’re hoping to lose weight.

The ah-hem, bottom line? Climbing builds strength, which is why it’s an integral part of the Spinning® program. However, to build the large quadriceps and gluteal muscles you fear, you’d have to use a very difficult gear for repeated and extended periods of time. During Spinning® class, climbs usually don’t last for more than a few minutes—not enough time to result in bigger legs or a bigger butt.

Remember:The Spinning® program recommends a 40-minute class, but it’s always your ride. When in doubt, ask your instructor to help you modify rides to meet your training goals.

And if you don’t believe us: Go find the biggest guy in the weight room and ask him how to get big legs and a bigger butt. It’s likely he’ll include the following: increased protein intake with calorie reduction and an emphasis on training with heavy weights.