Unlike, say, swimming pools, running surfaces are virtually everywhere. A trail, a street, a park, a beach—you can tie on your sneakers and just head out of the door for some exercise. Even if you have a favorite running path, it’s worth trying out new courses: Varying the terrain you run on brings new challenges for your body to respond to, fresh scenery to keep you engaged and a great opportunity to bust boredom and stay motivated. It’s also a smart way to prevent injuries; you won’t tax your body in the same way, run after run. There’s no “right” place to run, but it’s important to know the pluses and minuses of a running surface before you take to it, so you can stay safe and get the most out of your workout.
Asphalt and Concrete
Asphalt (roads) and concrete (sidewalks) are the most readily available outdoor running surfaces for many of us. They’re generally smooth and unlikely to trip anyone, except for those who encounter the occasional pothole or crack.
Keep in Mind: These are the hardest surfaces you can run on, and your joints may take a pounding as a result. Concrete is the slightly harder option of the two, which is why some runners may choose the side of the road, even when a sidewalk is available. But roads are typically “crowned” (slanted on each side) to help with water run-off. This grading can contribute to injuries, particularly if you always run on the same side of the street.
Tips for Running on These Surfaces: To protect yourself from the extra impact, make sure to wear supportive, well-fitting running shoes and replace them every 300 to 500 miles (when the cushioning breaks down). If you do run on the sides of roads, avoid those with dramatic slopes; consider heading for streets with less traffic, where you can run on the flatter part of the asphalt.
Grass and Dirt
Compared to running on concrete, hitting a grassy or dirt path decreases the force your body absorbs by 12 percent, which may translate to less risk of knee and foot injuries. The effort it takes to stay steady on trails’ uneven surfaces also helps work lots of tiny balance muscles in your legs that running on flat surfaces doesn’t.
Keep in Mind: Grass and dirt running surfaces may be smooth and well-groomed or riddled with obstacles, so you need to pay extra attention when stepping. While some runners find navigating rocks, tree roots and other trail bumps a fun change of pace, uneven terrain can make it much easier to twist or sprain an ankle, or reinjure yourself if you’re recovering.
Tips for Running on These Surfaces: Since trails may challenge muscles you’re not used to working, start slowly and let your body adapt. Practicing balance exercises, such as jumping up and down on one foot, can help strengthen the muscles you’ll engage on the trail. If you’re worried about getting hurt, stick to manicured paths instead of getting adventurous.
In addition to exciting your senses—the sounds of waves crashing, a gentle ocean breeze—running on sand helps you burn about 20 percent more calories per mile compared to asphalt. The extra resistance prompts your leg muscles to work harder to propel you forward, which also helps you tone.
Keep in Mind: While burning extra calories can be motivating, it also means your body is working pretty hard; your run may tax you more than you planned. If sand is very soft, extra strain may be put on your Achilles’ tendon (located in the back of your lower leg).
Tips for Running on This Surface: Sand running can be a great complement to running on firmer surfaces, and a fun way to shake things up on a beach vacation. Just don’t expect to go as far and as fast as you do on firmer surfaces. To make running on sand easier on your body, go when the tide is low and the sand is wet and packed.
Running on a treadmill may seem like it’s the same as hitting the streets, but the machine offers far more “give,” reducing the force absorbed by your joints by about 12 percent (just like grass and dirt surfaces). And you can’t deny the appeal of a running surface that is never affected by the weather.
Keep in Mind: Some studies suggest that your stride may be changed by your foot hitting a rotating belt instead of pushing off a static surface, which may cause foot pain. Beyond that, some people find treadmills to be “roads to nowhere,” which can make running monotonous. Running in place also burns fewer calories; since you don’t encounter wind resistance like you do when you’re in forward motion, your body uses less energy to move.
Tips for Running on This Surface: Set a 1 percent incline so that you reach the calorie burn you get when running on flat land. Check in with your body as you run: Tune into any discomfort and break (or change up your exercise routine) accordingly. If you plan to run a race and are training on a treadmill, but sure to mix in some asphalt time, too—your muscles and joints need to prepare for race conditions.