Cycling or Running: Which One Is Better for You?
Building & toning muscle
To be honest, if your only goal is to build muscle, running won’t help that much. Cycling, instead, could be a great way of increasing muscle mass in the lower half of your body. Of course, your hands and back muscles also benefit from riding the bicycle, but not nearly as much as the bottom half; therefore, if you want to build muscle, it might be wise to combine cycling with weight lifting that focuses on the upper part of your body so you can increase muscle mass symmetrically.
The perk of running, though, is that it engages all muscles equally and simultaneously. This makes it a great way to be toned and even increase bone resistance, which forms due to the impact of hitting the ground continuously.
Shortly said, running is great to tone muscles while cycling helps build them (but not equally).