Treadmill or Outdoors, Which is Best?

A look at the benefits of walking, on the trail and in the gym.

Mike Cox

I love to walk. It’s fun and easy exercise, good for everything from digestion to the ticker. But for years I could never figure out the best way to do it.

More specifically, inside or outside?

There are advantages to each, of course. When it’s cold and raining, or hailing and sleeting, indoors, in a nice warm gym seems like a no-brainer. Aside from the shelter, there’s televisions to watch and fresh water a few paces away and bathrooms and places to rest and maybe even a snack bar, depending on you gym, where you can get everything from protein bars to muscle milk.

I’m a member of one, and there are days where I’m grateful I am. And there are days I wonder if I shouldn’t shave a few bucks off my monthly budget and cancel my membership. I’m fortunate enough to live where the weather is beautiful most of the year. For me it’s easy to take advantage of nature, where I get so much more than just exercise. As fitness experts will tell you, a walk outdoors is about so much more than the steps. It’s inhaling nature and being with the trees and the fresh air and sunshine. Much as I value gyms, you can’t beat what a nice walk in a green environment does for you.

Research backs this up to the wall. There are numerous studies that show walking outside has an enhanced effect on our well-being. It decreases cortisol stress levels, blood pressure, boosts mood, enhances creativity, improves memory and cognitive function, and elevated serotonin. Fresh air can increase oxygen levels in the brain, and exposure to the great outdoors boosts cancer-fighting cells in the immune system.

Natural environments provides a quieter and less stimulating setting, allowing for better attention and focus. And exposure to natural light can help regulate your body's natural sleep-wake cycle or circadian rhythm. “You want to look at different buildings, trees, birds, everything," N’Namdi Nelson, an exercise physiologist at NYU Langone’s Sports Performance Center says. "That’s going to be healthier for you than just looking at a screen all day.”

There are other plusses as well. "There's more variation in your speed and your pace," says Dr. Jeanne Doperak, a primary care sports medicine physician at the University of Pittsburgh Medical Center. The varied natural terrain is more engaging (and challenging) than the monotony of a treadmill. That gives your muscles a more thorough workout. This could be an obstacle rather than a benefit if you have balance issues, and if you do, then maybe an indoor walk is for you, and there’s nothing wrong with that. All exercise is beneficial. But nature, as is so often the case, seems to better human efforts at so many turns. The general agreement among just about all physicians is it's important for people of all ages to spend time outside regularly. And that means even if you aren’t able to take long walks.

Make sure you have some allies at your disposal, though. Sunscreen is a must, and some brands and specifications are more effective than others, studies have found. And as is often the case with many pharmaceutical items, the best of them are not legal in the U.S. The plethora of available options can be overwhelming, which is why I’ve included links to lists above. There is even a type that’s formulated to minimize harm to coral reefs and other marine ecosystems.

Another key piece of equipment is shoes. Needless to say, you must have comfortable, well broken-in shoes or your walk will change from blissful to agony. If you have a pair of shoes that is “about to go,” meaning there are cracks and tears and your little toe is starting to poke out, don’t simply toss them and lace up new ones before your daily walk. Your feet will feel like they’ve gone through a meat grinder. Break the new ones in gradually, taking short walks with them, or just wearing them around the house and yard, for a couple weeks.

What if I have to walk indoors?

Older people and those with balance or other mobility issues may find an outdoor walk to be a challenge.

I walk primarily in an old neighborhood, where the streets are lined with beautiful old trees, primarily Coast Live Oaks. Their massive roots tend to tear up the sidewalks. One could easily trip and fall. Some people, particularly older residents, walk in the narrow, twisting streets. That presents its own hazards.

Indoor treadmills are ideal for those looking for a steady, smooth surface. If that’s you, starting with indoor walking workouts, ideally on a carpeted surface, may be best for lower impact on the feet (foot and leg nerves can take a hit) and a more steady gait.

True you’re missing the outdoors. But you’re still getting in a good workout, and that’s the most important thing. You can always experience the outdoors when the weather is better or you are not walking in challenging conditions. You can shop, have a picnic, take in a beautiful garden, stroll along the beach.

You can also get in your walks at home. Walking pads, which are small enough to fit under a standing desk, are a popular option to get steps in during the day. However, note that many walking pads don’t come with handrails.

Whatever works for you, do it! Walking is one of the best forms of exercise: It doesn’t take the toll on the body jogging can, it gets you out of the house (most of the time, at least, even if it’s to go to the gym), it can be a social activity (take a friend!) and it’s basically free. There aren’t too many other things in life with all those positive benefits.