“Will indoor cycling make my legs big?” I’ve been asked this question a number of times over the years. A few people told me their personal trainers told them that. Others just made the assumption based on the fact that we are constantly using our legs (not a bad assumption). The question was always asked as if people feared they would walk out of class with bulging quadriceps, calves and glutes.
I’m sure that I may have been asked this question more than some because....well....my legs are quite big. It is rare for me to find a pair of cycling shorts that fit comfortably without cutting of the circulation to my lower legs. For the record, I didn’t get my legs from cycling. Back in the day, my primary sport was baseball. Coming out of high school, I looked to have a promising career as a ball player until I blew out my shoulder. I was a catcher. Catchers find themselves sitting in a squat for most of their lives. To make matters worse, one of my early coaches used to have me (and the 2 other catchers on our team) run around the field in a squat position. I can only image what that must have looked like. My legs were so big during my last year of baseball that I was the only player who did not have his last name on their back. The back of my uniform read “Piano Legs”.
So it is understandable that someone would walk into my class, look down at my legs, and fear they would never be able to wear a skirt again after some indoor cycling rides with me. The fact is that cycling reduced much of the bulky-ness of my legs and toned them. No joke, my legs used to be twice the size as they are now. So why did this happen? First, cycling doesn’t provide high impact on the muscles (unless you crash into something which is unlikely indoors). Impact, such as when the foot strikes the ground when running or jumping, will cause the muscle to rapidly resist force resulting in an eccentric contraction. An eccentric contraction will cause the muscle fibers to lengthen as they attempt to stabilize the joints (resist collapsing or flexing). This impact can be very traumatic on the muscle resulting in micro-tears and muscle growth. Second, indoor cycling usually does not provide consistent muscle overload which would provoke more muscle fiber recruitment. Portions of a class may have some explosive efforts or muscular strength drills, but the majority of the time will be spent at low to moderate workloads.
Cycling is predominantly a high repetition activity. In general, high repetition exercise will serve to tone muscle because it promotes increased blood flow and muscle conditioning without the overload. Using weight training as a comparison, someone lifting weights to build muscle mass will target heavy loads and sets consisting of 6 to 10 repetitions. A person interested in toning their muscles will use lighter weight and sets of 15 to 20+ repetitions. Applying this concept to indoor cycling, we are pedaling thousands of rotations (repetitions) per hour*, which is going to have an overall toning and conditioning affect on the muscles.
So the answer is no, it is highly unlikely that indoor cycling will bulk up your legs. So ride away and advertise your class as the way to a beautiful, toned and fit body (at least the legs anyway).
* An average cadence of 80 RPM for a 60 minute class will result in 4800 pedal rotations for one leg.
Originally posted 2011-06-26 06:00:14.