Blood flow is the single most important thing for your brain, and 20% of the blood from every heart beat goes to feed your brain.
The more blood to the brain, the better your brain functions. So, if it makes your heart beat faster, that's good. Three hours a week of aerobic exercise will have your brain working at optimum.
What are good aerobic exercises? Bike riding, jogging, and, of course, sex.
Having sex increases blood flow to your brain,and releases chemicals that increase mental performance and releases endorphins which help reduce pain and increases cognitive function also it gets rid of stress which is always a good thing
Do NOT, however, have sex while riding a bicycle, even while wearing a helmet. This can be dangerous to you and others. There is a vibrating bicycle seat, HAPPY RIDE, which is a bike seat cover with a discreet, high-powered vibrator tucked inside.
I'm not sure this is a good idea simply because having a healthy orgasm while riding might cause you to lose control of the bike. Imagine trying to explain what happened."Well, you see, Officer..."