Cycling strengthens your heart, making it more efficient resulting in improved physical performance in both sport, recreation and general living.
Mountain biking is great for your lungs. Cycling in the wilderness around trees forces you to fill your lungs with clean, fresh and non-polluted oxygen which will flow through your bloodstream, clearing toxins and making you fell great.
Mountain biking is a low impact sport. Mountain biking takes care of your joints by being a low impact sport. There is no pounding associated with peddling which is good for preventing injuries both acute and long term.
Mountain biking builds your immune system. Just like when you were a kid, playing in the dirt helps to strengthen your immune system by exposing yourself to different kinds of bugs. A stronger immune system means you won't get sick as often and you will recover quicker from any illnesses you may get.
Mountain biking develops your sense of balance. Having a better sense of balance helps to prevent injuries while also improving your general coordination.
Mountain biking improves your reaction time. Flying down a trail at 40km/h and you come across a nasty rock section surrounded by trees, you need to pick you line FAST, otherwise you may be eating the dirt pretty soon. Other examples may include reacting to varying trail surfaces, that giant root sticking out at the end of the blind corner or reacting to the unpredictable actions of other riders.
Mountain biking makes you smarter. Cycling circulates vital fluid around your body pumping it through your muscles and through your brain. Better circulation to your muscles = better muscles so better circulation to your brain = better brain.
Mountain biking makes you better at mechanics. Repairing or tinkering with your bike improves your awareness of how things work like wheels, bearings, springs etc. The more exposure you've had with the parts on your bike, the handier your repair skills may become
Mountain biking is a social sport. Cycling can also maintain your social health where you can easily link up with some of the friendly mountain bikers of the world.
Mountain biking is fun! Any outdoor physical activity that you enjoy and want to do more of is the best thing to keep happy and healthy.