I'm a cyclist. I've been riding a road bike for about 20 years, now. I do it mostly to stay physically fit, but it also definitely helps with my mental health. I like riding alone out on rural roads. In the same way that many people have insights and find inspiration in the shower, I can easily turn off my prefrontal constraints and let my mind wander in the saddle. It's like a productive meditative state. I've had breakthroughs on the bike with songwriting and with sociological research projects. Mostly, though, it's just a way to (dis)engage in a relatively undemanding, repetitive mental/physical practice that unclutters my mind. (It turns out cranking pedals and maintaining balance is a lot like washing one's hair but lasts far longer.)
A problem, though, that I've encountered from almost the first time I went on a bike ride as an adult is that motorists regularly endanger and disrespect cyclists. While cycling is pretty safe, it can feel harrowing. What is more troubling, though, is the aftermath of those troubling encounters. When my life is threatened, I am understandably angered. Think about the times when you've been driving your car and another motorist does something stupid that could have killed you or others. You likely got mad. This is not "road rage"; it's a justifiable and natural reaction. It's only amplified when I'm on my bike because while car accidents are dangerous, as a cyclist, I have about 10% of the mass of a typical car and am protected by a helmet, not crumple zones, airbags, a seatbelt, etc. Add heightened adrenaline levels from the exercise and stress, and these emotions are exagerated. You'll forgive me for being a bit enraged when someone chooses to risk my wellbeing because they're in a hurry. When I'm behind the wheel of a car and some idiot cuts me off, I can use the horn to alert them to their mistake. There is no such mechanism on my bike so I end up yelling and, sometimes, using my middle finger.
The double-whammy of having my life endangered and then feeling irrationally guilty for the rest of my day from expressing righteous anger erases the mental and emotional benefits of cycling for me. I was stubborn enough in my youth to push past this, but now, I have changed my habits. For the last month or so, I have been riding nine laps around my 1.74-mile neighborhood loop instead of doing my typical 17-mile ride through the local countryside. It's not the same. It's better than feeling bad about getting mad, but it's still sad.