Treadmill Workouts for Race Training from the 5K to Marathon

Runners all across the country are training for spring races, but winter weather isn’t exactly conducive to interval workouts and long runs. Ice, snow, and buttery cold temperatures can make outdoor training difficult – and while the treadmill is a safer alternative, it’s not always the most fun.

The monotony of running with no change in scenery or perception of moving can mentally fatigue even the strongest of runners. The origins of the treadmill illuminate this phenomenon: the treadmill was originally used as an instrument of torture and reform for prisoners in 19th century England, due to its monotonous nature. It’s no wonder that we runners opt to battle brutal winter conditions rather than run on the treadmill; however, slick or snowy roads, limited daylight, and extremely cold temperatures make speedwork incredibly challenging to do outdoors in winter.

You can find a variety of treadmill workouts online, but not all treadmill workouts have the specificity of your race in mind. For runners training for spring PRs, these treadmill workouts from the 5K to marathon will make the treadmill fun while optimizing your training for your race.

Can You Train for a Marathon on the Treadmill?

When the weather keeps your runs indoors for weeks, you may start to wonder: can you train for a marathon on the treadmill? While treadmill running has less impact than outdoor running, it is still running. Doing a week or two of all of your runs on the treadmill is certainly better than skipping runs because you feel the treadmill “doesn’t count” (it does).

While long runs on the treadmill can seem daunting, if you need to take your long run indoors, do it! (Or, if it’s just one week and you have enough time in your training, adjust your training schedule.) A few deliberate tweaks can help you get through a long run on the treadmill. A 20 miler on the treadmill is still 20 miles, even if you did not battle the elements.

If you run mostly on the treadmill your entire training cycle, you may need to adjust your expectations on race day. You can still finish a marathon even if you do most of your training on the marathon. However, you may need to anticipate that the hard outdoor surfaces will cause more fatigue, and adjust both your goals and your pacing accordingly. (This article will guide you through more specifics of how to train for a race on the treadmill.)

Treadmill Workouts from the 5K to Marathon

With the exception of hill workouts, set your treadmill incline to what feels most comfortable. This may be 0% or 1%, based on your preference, gait, and type of terrain you usually run on outside. Do not set speed intervals any higher than 1.5%, lest you change your speed intervals into hill repeats.

5K Treadmill Workout: Hill Repeats

The workout:
1 mile warm up
3 x (1 minute uphill hard, 1 minute easy, 1 minute uphill hard, 1 minute easy, 2 minutes uphill hard, 2 minutes easy)
1 mile cool down

Perhaps this is just my perception, but I feel like I am going to fly off the back of the treadmill when running at 5K pace or slightly faster. The treadmill skews your perception of effort, which can make 5K pace feel harder than the same pace would on a track.

According to a 2013 study published in the International Journal of Sports Physiology and Performance, hill repeats of any length resulted in a 2% improvement in 5K time for well-trained runners. Hill repeats at 5K effort (not pace) significantly improve running economy, which translates to how much oxygen you use at a given pace. The higher your running economy, the faster you can run.

For hill repeats on the treadmill, set the incline to 4-6% and set the pace to what feels hard. Do not run these intervals at goal 5K pace – you will burn out before the end of the workout. Aim for either a pace that feels like an 8-9 on a scale of 1 (walking) to 10 (100 m sprint), or use this handy chart to find your approximate equivalent 5K pace for a given incline. For the recovery intervals, set the incline to 0% and run at a very easy effort.

10K Treadmill Workout: Progressive 1K Intervals

The workout:
1-2 mile warm up
2 x 1K at 10 seconds per mile slower than 10K pace (2 minute recovery jog)
2-4 x 1K at 10K pace (2 minute recovery jog)
2 x 1K at 10 seconds per mile faster than 10K pace (2 minute recovery jog)
1 mile cool down

Intervals are one of the best workouts for the treadmill, but long repeats can become monotonous after the fourth or fifth interval. This variation on an effective 10K workout – 6-8 x 1K at 10K pace – starts with intervals 10 seconds per mile slower than 10K pace (~15K pace) and finishes at 10 seconds per mile faster than 10K pace (~5K-8K pace). The change in pace maintains variety throughout the entire workout and breaks the run up into more manageable segments.

If your treadmill has a visual track, 1K equals 2.5 laps around the track. Alternatively, you can either run 0.62 miles or, for an easier number, 0.60 miles. (If you are a lower volume runner or short on time, shorten the repeats to 1/2 mile.)

Half Marathon Treadmill Workout: Race Pace Mile Repeats

The workout:
1-2 mile warm up
5-7 x 1 mile at half marathon pace, with 1.5 minute recovery jog
1 mile cool down

This variation on mile repeats (one of my favorite workouts for the half marathon) focuses heavily on race pace. Short rests break it up, so the workout pass by more quickly. This workout is challenging, so you want to complete it about 3-6 weeks before your marathon.

After a warm-up, run 1 miles at half marathon pace. Depending on your overall weekly mileage and fitness level, you would complete five to seven of these repeats. If that feels too challenging or too time-demanding, aim for 4 repeats.

Marathon Treadmill Workout: Mixed Bag Long Run

The Workout:
2-4 miles easy, varying the incline from 0-3% every few minutes
5-6 x (1 mile at marathon pace, 1 mile easy)
2-4 miles easy, varying the incline from 0-3% every few minutes

Treadmill running seems to distend time, and suddenly a 10 mile long run feels like a 30 mile run. But during marathon training, you can’t skip on those 16, 18, and 20 mile long runs, even when the wind chills are below zero.

The solution to enduring long runs on the treadmill is to divide them into manageable segments and constantly vary incline and pace. This workout can be adjusted for 14-20 miles, depending on your long run for the week. During the easy paced miles, you vary the incline every few minutes to engage your mind and activate different muscles. The middle miles consist of repeats of 1 mile at marathon pace, 1 mile easy – enough variety to beat boredom without turning your long run into a race effort.

Training for a Half Marathon on the Treadmill, Recapped

Whether you are training for a half marathon, marathon, or shorter distance, these workouts are intended to be hard workouts – not everyday runs. You still want to keep a majority of your workouts at an easy, conversational pace – even on the treadmill.

When training for a half marathon or marathon on the treadmill, be mindful to adjust your training paces if the effort feels inappropriate. Warm gyms can often raise heart rate and effort level, so you may find that you need to slow down by a few seconds per mile on workouts. That is okay! The benefits come from the appropriate training intensity, not an exact pace. (Here’s a handy treadmill pace chart!)

One final note on all of these treadmill workouts: set the paces and distances based on what the treadmill says, not your watch! Garmin and other running watches are not accurate on the treadmill (learn why in this article.)

Download a marathon or half marathon training plan to run your best race!