When you step on the pedal, you also force more nerve cells to fire. When these neurons glow, they increase the production of proteins such as brain-derived neurotrophic factor (BDNF) and a compound called nogin (yes, actually) that promote the formation of new brain cells. The result: you double or double the production of neurons - you actually build your brain, says Christie. In addition, you release neurotransmitters (messengers between your brain cells) so that all new and old cells can communicate with each other to function better and faster. This is quite advantageous for cyclists.