"Breathing fresh air opposed to the recycled kind can create a feeling of euphoria, which comes from the body's release of feel-good endorphins," Gotlin says. "It's not that your muscles respond better to it, but rather your mind does, which in turn makes you want to work harder."
Exercising outside also creates greater feelings of revitalization, energy, and positive thinking than does working out indoors, according to a report published in Environmental Science and Technology. What's more, after an 30-minute walk in the park, 71 percent of people feel less stressed, while 72 percent of people who take their walks indoors actually feel more stressed.
You'll Fight Germs
Gyms aren't always the meccas of health we make them out to be. A whole slew of studies show that gyms are breeding grounds for germs and bacteria. MRSA is the most dangerous super bug you can catch at your fitness facility—it's resistant to most antibiotics and can cause fever, rash, wounds, and chest pain. Other less harmful infections include athlete's foot, boils, herpes simplex, and ringworm, according to the National Athletic Trainers' Association.
You can avoid these hazards by washing your hands often, changing your socks daily, using foot powder, wiping down equipment before and after use and wearing flip flops in the shower. Or you can simply take your training to the streets (even Rocky left the boxing ring every once in a while to run around his 'hood). Indoor air is two to five time more polluted than outdoor air, according to a study from the Environmental Protection Agency. If you've ever walked into a stinky gym, you know exactly what's up.
You'll Think More Clearly
Breaking a sweat outside may make you smarter.
"Humans were hunter-gatherers and farmers for some 300,000 generations; have been industrialized for only six to eight, so we are outdoor animals living largely inside," says Jo Barton, Ph.D., the lead author of a 2011 study that analyzed the mental health of 53 people who were involved in indoor or outdoor activities for six weeks. "Closeness to nature increases our well-being—it has an immunizing effect by protecting us from future stresses and helping us concentrate and think more clearly," she says.
You'll Work Out Whenever You Want
How's this for empowering: The outdoors is always ready to go. No class schedules, no waiting in line for the elliptical machine, and no need to dig out your exercise bands from the closet. You can fit fitness in whenever you have a chance. Even a 20-minute intense workout in the great outdoors will do the trick: A single high-intensity workout is three times more effective at burning fat than endurance training, according to a study published in Metabolism.
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