Running once a day probably feels quite sufficient for most long-distance runners, so the notion of a training plan that involves running twice a day may sound unnecessary and perhaps even a bit foolhardy.
However, running twice a day – or doing Double Sessions – is not just for elite runners, and it can actually be quite beneficial for higher mileage runners if integrated correctly.
While beginners should stick to single runs for at least a couple of years, experienced half marathon runners, marathon runners, and ultra runners may find that adding a second training session a few days a week.
What Are the Benefits of Running Twice a Day?
#1: Helps Increase Your Mileage
If you are trying to increase your weekly mileage, perhaps with marathon training, adding a second run one or two days a week will help you hit high mileage without making your long runs even longer.
While it’s tempting to look for shortcuts to build up your endurance, there really is no substitute for simply putting in the miles, and double sessions allow you to do so without sacrificing a rest day.
#2: Promotes Delayed Fatigue And More Efficient Recovery
Running twice a day forces your body to adapt and use your glycogen reserves more efficiently1Knuiman, P., Hopman, M. T. E., & Mensink, M. (2015). Glycogen availability and skeletal muscle adaptations with endurance and resistance exercise. Nutrition & Metabolism, 12(1). https://doi.org/10.1186/s12986-015-0055-9 because even with good fueling and hydration after your first run of the day, you may be in somewhat of a depleted state for your second run.
If done consistently, this can help your body adapt to using glycogen more sparingly, which will result in delayed fatigue.
A second run will also increase blood flow to the muscles, resulting in faster recovery.
In this way, you can do recovery runs as “active recovery” as your second run on double run days, which may help you feel better the next day despite having run twice in the day.
These types of adaptations can ultimately lead to improved running fitness.
#3: Helps You Learn To Run On Tired Legs
Your legs will be tired on the second run of the day, forcing your body to adapt to running while feeling less than fresh and fully rested.
You may also feel mentally tired, and you will need to develop strategies to keep yourself focused and motivated for your second run.
These adaptations and skills will be useful when racing, particularly during the last few miles when you are physically and mentally exhausted.
#4: May Be Easier To Schedule
Long runs often take up a significant amount of time and may be difficult to squeeze in around other obligations, but shorter runs may be easier to incorporate into your day.
While finding enough time for a two-hour run may seem impossible, getting out for an hour before work and an hour after work may feel more doable.
#5: May Be Easier To Manage Mentally
Even if scheduling a long run isn’t a problem, you may be unenthusiastic or even a bit anxious about tackling longer runs. In this situation, breaking a longer run up into two shorter runs may help make the miles feel less monotonous and stressful.
This trick may, therefore, make it more likely you will do your runs and may also make them more enjoyable.
What Are the Cons Of Running Twice a Day?
#1: May Not Promote Endurance For Newer Runners
For newer runners who are working on improving their aerobic endurance, there really is no substitute for including a gradually longer long run every week.
That is, to increase your endurance, you must run longer distances, and exchanging a long run for two shorter runs will not be as helpful in promoting aerobic improvement.
#2: May Hinder Recovery
While running twice a day may lead to improved recovery times, it may also result in increased fatigue, making it difficult to run the second run, or even the following day’s run, at the desired pace or for the planned distance.
In this situation, double runs may actually result in decreased speed or endurance.
#3: May Lead To Burnout
Runners may find that running twice a day is mentally draining.
For example, instead of enjoying the feeling of accomplishment after finishing a morning run, a runner may be so focused on the second run that some of the mental benefits of running may be lost.
Running twice a day may also feel burdensome, resulting in less satisfaction with running overall and even overtraining.
#4: May Increase the Risk of Injury
Common sense suggests that increasing the frequency or intensity of runs may lead to injury or exacerbate a previous injury.
Therefore, running double sessions could potentially be problematic from this standpoint.
Also, breaking a longer run into two shorter runs may tempt you to run faster for each of those sessions, given they are shorter and will feel more manageable at a faster pace.
This will increase the risk of burnout and possible injury, as you will add unnecessary intensity to your training week.
#5: May Be Difficult To Schedule
Some runners may find two shorter runs are easier to fit into the day than one longer run, but other runners may find that carving out time for two runs, no matter how long they are, nearly impossible.
In this situation, the stress of trying to add a second run may outweigh the benefits.
How To Add Double Sessions Into Your Routine
In general, double sessions are better suited for seasoned runners who have been averaging at least 50 miles per week for several years, but less experienced runners can also try adding a second run once a week if they follow these guidelines.
If trying double sessions sounds intriguing, keep reading to find out how to incorporate them into your running routine.
For experienced runners:
Experienced runners may want to try adding a second run on a day with a harder workout as a “shakeout run” to help recovery in the afternoon or evening. This run can be between 5 and 8K, run at an easy, conversation pace.
You could also use a double session to add mileage after an easy run in the morning, especially if you need to split up your runs due to time and scheduling.
Also, runners training high mileage won’t want to exceed 16-18K in one shot if it isn’t a long run. Here, is a great opportunity to run a double session in the evening to up your volume.
The bottom line for experienced runners is that there are many ways to incorporate double sessions, and as long as done carefully, second runs can be added in a variety of ways based on circumstances, goals, and preferences.
For less experienced runners:
Less experienced runners can still try double sessions, but should generally not do more than one double run per week and should consider just adding a short, easy run — perhaps 20 to 30 minutes at a conversational pace — to an existing training schedule or dividing a mid-week medium-length run into two separate runs.
For these runners, it is important to maintain the weekly long run, as well as any other key workouts such as tempo runs or speed sessions, as these workouts are necessary for improved endurance and speed.
Is it Ok to Run Twice a Day? Other Factors To Consider
Here are some other factors to consider when adding doubles to your workout routine:
Fuel and Sleep
Running twice a day can be taxing on the body, so if you decide to try double sessions, you should be sure you are getting enough calories to fuel these runs and enough sleep to adequately recover from them.
Without sufficient nutrients and rest, double sessions can wind up wearing you down more than they are building you up.
Timing
Although there are no hard and fast rules for the timing of double sessions, most experts agree it is best to wait at least five hours between runs and, optimally, a bit longer, in the seven to nine-hour range.
Shorter times between runs do not allow the body adequate time to recover sufficiently for the second run, and longer time results in diminishing returns on the benefits of double sessions.
Warm-ups, Cool Downs, and Recovery/Rest Days
When adding second runs to your routine, it becomes even more important to include a warm-up before every run and at least a short cool down after every run in order to avoid injuries and minimize muscle soreness.
It is also important to maintain recovery days and truly rest on your “off” days to avoid overtraining.
10% Rule
Runners have long been advised to avoid increasing their weekly mileage by more than ten percent per week, and this rule holds true when adding double sessions.
Therefore, while adding a second run to a day is a good way to increase mileage, that increase should still be gradual in order to avoid injury or other overtraining problems.
Be Flexible and Cut Back If Necessary
While you may want to embrace double sessions, if you are struggling to get through your runs, are having difficulty maintaining previous paces, or are just feeling extra tired or sluggish, be willing to make adjustments.
You may want to either eliminate your second runs altogether or make the second run shorter or at an easier pace. Once you’re feeling better, you can try adding a second run again, but be flexible if you notice diminishing returns on your efforts.
Is Running Twice a Day Good for Weight Loss?
With double sessions, your body goes through two periods of increased resting metabolic rate, which may help with weight loss.
Essentially, if you run twice a day, you will experience two post-run spikes in your resting metabolic rate, which could be helpful if you are trying to shed some pounds.
Running twice a day may also simply help you burn more calories and therefore aid in creating a calorie deficit.
It is important to take in sufficient calories to fuel your double sessions, so maintaining a calorie deficit for weight loss can be somewhat tricky, and consultation with a knowledgeable coach or sports nutritionist may be helpful.
Related: Working Out Twice A Day: Pros, Cons + How To Maximize Results
I run twice a day, every day, very slow, usually about 8-10 miles. I had never thought of what exact benefits it gives, other than I had noticed it works really well for me mentally and physically. One obvious thing you point out, and other articles, is that running twice a day teaches your body to recover faster. I also had never considered the 2 elevated spikes to my resting metabolism. I am fortunate that I have a low stress job and plenty of time to eat, nap and sleep and it’s really key, even when you are running as slow as I am (about 9:30-11 minutes/mile).
I am in the fortunate position that I retired in my late 50’s and have all the time in the world to indulge my passion – running. My current programme is two days on, followed by a rest day, and repeat, repeat, repeat. I typically run 7 miles each running day, split between a morning 3 miler and an afternoon 4 miler – adding up to an average 35 miles per week. The great thing about running doubles is that it’s a great way of getting the miles in when the weather is extreme. At the moment, the weather is hot & humid and a single 7 miler would be far more tiring than the two shorter runs detailed above. One other thing to note on the subject – one day (when my wife was away !), I ran a record (for me) 5 times in the day. Five times 3 miles with three hour gaps. The last 3 miler was tough going but the promise of a wallow in a hot bath made it doable. The next day was a ‘rest day’ and the day after that I got back to my usual groove with no adverse reactions. Though I only did it the once, I would definitely do it again, if the ‘stars were aligned’, so to speak.
sounds like a great routine!!!