Is Running Twice a Day Beneficial?

6 myths about running twice a day

“Doubles” or “two-a-days,” are running’s answer to graduate degrees in the education world. By themselves, they don’t imply that you’re outstanding in your field, but they do establish that you’re serious and persistent about your goals.

One backdoor way to determine whether doubles are something you should entertain is to slay a few common misconceptions about them.

1) Once you start running twice a day, it’s a forever thing.

Nope. Sometimes doubles are invoked for specific training blocks and they can be put on ice after the goal race is in the books. It might just be that you want to increase your fitness quickly and without the breakdown of longer runs.

2) Starting two-a-days implies working toward a regular, even everyday, commitment to doubles.

While you’ll meet a lot of higher-mileage runners who run doubles five times a week (or do them a set number of times each week), there is no rational basis for not simply adding them in when you feel up to it, be that once every two weeks or every day (the latter, of course, after a proper ramping-up).

3) You shouldn’t make the jump to doubles until you reach a certain mileage level.

This is an inversion of the (perfectly sound) idea that above a certain mileage level, you almost certainly should incorporate doubles. But there’s no logic in it. There are a lot of smart reasons to add a second daily run a few times per week. The most obvious ones are that you can add mileage safely and in a less time-consuming manner. For example, you might not have time for a 10-miler during your day, but you probably have time for two 5-milers. Also, if you run a 16-miler as a single daily run, you’ll likely need more recovery time from that than you would if you ran two 8-milers.

READ MORE: How Far Should You Run in Training?

4) Two-a-days are for only elite runners or people aiming to be elite.

Incorrect. See above. While you’ll see a lot of double workout days in the training logs of top runners, that doesn’t mean that speedy pros have a monopoly on them, any more than quality clubs or expensive putting lessons are the sole purview of professional golfers. Beginners and intermediate runners can benefit from running twice a day as a means to safely add to their weekly mileage, recover better and increase aerobic fitness.

5) Your longest/hardest effort of a double-run day should be in the morning/evening.

Spot the problem yet? The answer here is it doesn’t really matter when you run your harder workout of the day. It certainly makes logical sense to get your harder run out of the way first because it allows your second run of the day to be more of a recovery-based effort. By default, it will be less mentally and physically stressful later in the day if your second run is an easy run. However, there are plenty of situations in which it makes sense to run harder during your second run of the day. You might need a slow run to start your day, depending on what kind of recovery your body needs. If you’re not a morning person, it might be hard for you to run faster efforts in the morning before you really wake up. It also might be that you’re running with a group of runners in the afternoon or evening that will help push you to your goals in the afternoon.

6) You’re more likely to get injured if you adopt double-run days on a regular basis.

There’s no evidence this is the case. Some people, in fact, stay healthier and more fresh distributing a given workload across a greater number of workouts, because running while tired—such as in the final 20 minutes of a 10-miler—often puts people at a greater injury risk than a pair of 5-milers thanks to the form breakdown, glycogen depletion and muscle tissue damage that strike more often in longer bouts of perambulation.

READ MORE: Three Ways to Run More Miles Safely

Kevin Beck

Kevin Beck is a longtime contributor to various endurance-sports publications, including Runner’s World, Competitor and Triathlete. A former 2:24 marathoner, he has coached a range of athletes from high school to professional the professional ranks, and is the co-author of “Young Runners at the Top” and the editor of “Run Strong.”