Sick of spending time in sweaty, crowded gyms? Why not turn to the great outdoors. Not only will using mother nature as your fitness playground look to save you money but studies have proven it is better for your health.Cycling in the UK is easy, fun and accessible to everyone. Here are five good reasons to grab your trainers, mount your bike and head for the hills:1. Rocket your levels of Vitamin D. With many of us trapped in the confines of our office for the majority of the day, don’t put yourself back into a small, confined space such as a gym after work. Sunlight on your skin (we aren’t talking sun worshipping here) sparks vitamin D production, which has been suggested to fight a magnitude of conditions from osteoporosis and cancer to depression and heart attacks. Try to combine this limited sun exposure with a good source of vitamin D supplements to secure a healthy regime.2. Work yourself harder! Instead of sitting on a stationary spin bike why not grab your mountain bike and head for some off-road cycling, which will test you against the elements and push your body to its limits. If you make getting outside a goal, that should mean less time in front of the television and computer and more time walking and doing other things that put the body in motion.3. Improve your concentration Multiple studies have found that children with ADHD focus better after being outdoors. Spending some time in a ‘green’ setting such as parks or gardens reduces symptoms of ADHD when compared to time spent indoors. The findings have been consistent regardless of age, gender, socioeconomic status, region or severity of diagnosis. So if you find you have trouble concentrating why not try some outdoor activity to help you focus.4. Prevent Injuries. Exercising on a natural surface can have tremendous benefit on your musculoskeletal system. In order to continue to improve musculoskeletal health uneven or natural terrain like grass fields, trails, hills, and other obstacles should be tackled. This can significantly decrease the risk of foot, ankle and knee injuries.5. Get that happy feeling. According to Dr. Andrew Lepp at Kent State University, outdoor activities can prevent and reduce stress, increase self-esteem, and offer a sense of challenge and adventure. So if active outside pursuits replace inactive slumps in front of the TV, it might also mean more smiles.