How to Train for a Marathon on the Treadmill

runner on treadmill

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Are you planning to run a marathon or half marathon? Sometimes the weather can make it challenging to do your training runs outdoors. Hot climates make long, hot miles difficult, and cold weather conditions can also interfere with workouts.

For these reasons, some people wonder if they can train on a treadmill instead. But can treadmill training adequately prepare you for the race?

While there are some differences between outdoor and treadmill running, there are many benefits of treadmill running. Running indoors can be an effective (and safe) way to train for races. But it is important to log some miles outdoors on roads to fully prepare for the race.

Benefits of Treadmill Training

In some respects, treadmill training provides better preparation for race-day conditions —especially if you are training in the winter for a spring marathon. Surprised?

Your marathon will most likely be in warmer weather. Running at room temperature will help you get acclimated to race-like conditions.

The treadmill also provides a good opportunity to test out some race day outfits since you most likely won't be wearing your cold-weather running clothes during the marathon.

Treadmill training can be beneficial for marathoners who are training for a spring marathon in the winter. Indoor conditions are not only safer but room temperature running is more likely to prepare you for a warm weather marathon.

But even if you are not dealing with a change of season, doing some workouts on the treadmill can benefit marathoners-in-training. Consider some of these advantages of indoor running.

  • Mental prep: The treadmill helps you prepare for some of the marathon's mental challenges because you have to work through boredom while running on a treadmill.
  • Practice: Treadmills also give you time to practice a good running form (as long as you don't grip the handrails).
  • Real-world stimulus: You can mix up your treadmill workouts to better simulate real-world running conditions. Change the incline and use decline features if your treadmill has them.
  • Set the pace: The treadmill allows you to set specific interval times and interval speeds for pace training.
  • Safety: Running on the treadmill is safer if you need to train late at night or early in the morning when it is still dark.
  • Convenience: Parents with children don't have to arrange childcare if they run on a home treadmill instead of outdoors.

Different Types of Treadmill Training

The various types of treadmills can also offer different benefits to runners.

Automatic Treadmills

Most gyms have automatic treadmills. This style allows you to enter a pace and incline to set on an electronic panel. There is usually a start and stop button to begin or end your workout.

These treadmills are beneficial for workouts that require a specific time, incline, or speed setting. These workouts may include:

  • Speed interval training: Run short intervals faster than race pace, then recover at a slower speed and repeat.
  • Hill interval training: Run at an increased incline for a short time segment, then recover on a flat surface and repeat.
  • Pyramid workouts: Similar to speed or hill intervals but each interval involves incrementally increased effort (either speed or incline) to a set goal. Then the intervals involve incrementally decreased effort until the end of the workout.
  • Tempo runs: Run at a challenging but steady pace for a set amount of time or mileage.

Manual Treadmills

More and more health clubs now provide manual or non-motorized treadmills. These treadmills do not have a traditional keypad or electronic input. Instead, you step onboard the belt and start moving.

Some manual treadmills are limited in terms of pace. But many newer models are not only limited, but they offer additional challenges that can be helpful for runners. For example, some are curved for increased endurance and stamina.

But even without the curve, non-motorized treadmills are preferred by some runners because they provide no electronic assistance. Instead, the belt moves with energy generated by the runner's movement. In many ways, this more accurately simulates actual road conditions.

Treadmill Limitations

Even though indoor running has its advantages, there are also drawbacks to treadmill training. Before you rely too heavily on treadmill workouts for a marathon or half marathon training, these should be taken into account.

First, many gyms limit the time each client can spend on a treadmill. You may not be able to put in more than 30 or 60 minutes per workout, so your mileage will be substantially limited. Early in your training, this isn't a problem. But eventually, you'll need to log more miles. If you have a home treadmill, you may not have the time restrictions.

A long training day is necessary to build endurance, and it will get progressively longer in the weeks leading up to your race. It also toughens your feet, so you will be less likely to get blisters on longer runs.

Another drawback is that many treadmills only have incline and speed settings. Very few have decline settings. That means that your training may help you prepare to go uphill, but not downhill.

Downhill running uses different muscles. Your feet also rub differently in your shoes. If your marathon course has hills, you should prepare your body for these challenges.

Lastly, you won't challenge your balance or form with different surfaces, curves, and maneuvering around obstructions as you do when running outdoors.

Running on a treadmill does not prepare you for the road conditions that you'll be challenged with during your marathon, including pavement variations, wind, curves, and possible downhill running.

Combine Treadmill and Outdoor Training

If you have access to a treadmill and plan to have challenges that will limit your outdoor training, such as weather or schedule limitations, try combining treadmill training with outdoor runs to maximize your race-day potential.

If you are training in severe heat or cold, look at the weather forecast for the upcoming week and plan your outdoor runs for the best possible weather days.

Weather conditions may still be less than ideal, but then again, you have no control over race-day weather either. Try to make your outdoor run your long run, so your body gets used to road running for long distances.

You can even combine the workout by doing some mileage on a treadmill and then suiting up and doing more of it outdoors. Running outside for long runs also means that you won't have to deal with getting bored doing double-digit miles on the treadmill.

If schedule limitations require treadmill training, plan your long run on your calendar and protect that workout from work and home interference. Then fit in treadmill workouts as time allows.

If your gym has time limits on the treadmill, put in the total amount of time allowed and take a break to do other cardio exercises. Add indoor or outdoor running, walking, elliptical, or rowing machine. You can even hit the stairs and do incline training in the stairwell.

If you can return when appropriate to put in another block to time running on the treadmill. If your break didn't maintain your heart rate, be sure to do a warm-up at a leisurely pace before increasing the speed and incline.

Doing long runs outside and some shorter workouts on a treadmill can be a great way to navigate schedule or weather challenges during marathon training.

A Word From Verywell

There are many ways to use a treadmill to make the most of your marathon or half-marathon training. Be mindful of the drawbacks of running indoors, and be sure to challenge yourself with long outdoor runs as much as possible. Then use indoor days to do targeted speed, incline, and tempo runs as needed.

1 Source
Verywell Fit uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
  1. Barnes KR, Hopkins WG, Mcguigan MR, Kilding AE. Effects of Different Uphill Interval-Training Programs on Running Economy and Performance. International Journal of Sports Physiology and Performance. 2013;8(6):639-647. doi:10.1123/ijspp.8.6.639

By Christine Luff, ACE-CPT
Christine Many Luff is a personal trainer, fitness nutrition specialist, and Road Runners Club of America Certified Coach.