Treadmill vs. Outside Running

Which to Use Depends on Your Goals

Is a treadmill as good a workout as running outside?
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The debate over whether running outside or on the treadmill is a better workout isn't new. There is no simple answer because there are pros and cons depending on the type of athlete you are and your training goals.

Treadmills are one of the most popular pieces of cardiovascular exercise equipment both at home and in the gyms. Treadmills make it easy to put in a fast, effective workout in less than ideal weather, and many people find it safer and more appealing to run or walk indoors.

For the thousands of health club runners and walkers, the treadmill is a good friend. And even elite athletes will turn to the treadmill on occasion, although it's more likely they will do the vast majority of their training miles outdoors on tracks, trails or pavement.

Treadmill Running Pros

Here are reasons you may want to run on the treadmill:

  • There are no weather, temperature, or terrain issues.
  • You can stop anytime you need or want.
  • You can workout while watching television, videos, or online content.
  • The smooth, cushioned surface is easier on the joints.
  • You will have fewer concerns about personal safety.
  • You can have easier access to restrooms and water when needed.
  • You don't need a running partner.

Outdoor Running Pros

You may want these advantages of outdoor running:

  • You can run anywhere.
  • It's much more functional in simulating daily activities.
  • It provides sport-specific training for road races.
  • You get to enjoy the scenery, breathe fresh air, notice changing seasons, and enjoy nature.
  • It's generally more challenging and you may expend more calories.
  • It's likely to be more motivating. You must complete a distance goal and can't just stop and get off.
  • You may have a greater feeling of accomplishment running outside.
  • You can take new routes and see something different every day.
  • It's a good way to exercise your dog while getting in your workout.

Differences in Your Running Workout

In general, athletes can get a similar workout on a treadmill as running outside as long as they maintain the same effort level. This is where there can be a big difference in indoor vs. outdoor running. You can usually judge effort level based on your heart rate or your rating of perceived exertion (RPE).

If, however, you run the same pace on the treadmill as outside on the flat pavement, you will expend less energy on the treadmill. This is due to the lack of wind resistance, terrain changes, and the movement of the treadmill belt to help propel you along. In order to compensate for the treadmill's momentum, older studies found that simply raising the treadmill incline to at least one percent will better simulate the energy expenditure of walking or running on flat pavement outdoors.

Who Should Run Outdoors?

If you are training for an outdoor running or walking event, obviously, you will want to train for the race conditions, which means getting outside. It's fine to do some of your training on the treadmill, but try to do at least 60 percent of it outdoors in order to train your body for the real deal. You'll be much more prepared for the demands on your muscles and joints by running on varied terrain if you run outdoors. You'll also become accustomed to running in varied weather conditions and learn what to wear for different temperatures.

Another important consideration is that many treadmills don't have a decline feature to simulate downhill running, which is essential if you are running an event that has uneven, or varied terrain. Similarly, there aren't turns on a treadmill, which is another important adaptation your body needs to make if you plan to run outside.

Who Should Run on a Treadmill?

If your goal is simply to log cardiovascular exercise minutes, a treadmill will allow you do that conveniently. A treadmill is a good solution if you live an area where outdoor running is limited due to weather, lack of nearby safe and pleasant running environments, or lack of a running partner. If you find excuses for not running outdoors due to scheduling or convenience you may be more consistent in getting exercise on a treadmill.