Should Runners Train Twice Per Day?
Last update June 22, 2026 by Etienne Durocher
Benefits, Risks, and Who Actually Needs Double Runs
At some point, many runners become curious about double runs.
They hear elite athletes talk about running twice per day. They see professional marathoners logging morning and evening sessions. They notice experienced ultrarunners splitting their mileage into multiple runs and begin wondering whether they should be doing the same.
The question seems logical.
If one run helps build fitness, wouldn't two runs build even more?
The answer is both yes and no.
Like many aspects of endurance training, the value of double runs depends entirely on context. For some runners, running twice per day can be an effective way to increase training volume, improve recovery between sessions, and support long-term development. For others, it creates unnecessary fatigue while adding very little benefit.
The challenge is that many runners ask the wrong question.
Instead of asking whether double runs work, they ask whether they should do them.
Those are two very different questions.
Double runs absolutely work. Elite athletes have used them for decades. Many successful marathon and ultramarathon runners continue using them today. The real question is whether they make sense for your current training level, goals, recovery capacity, and lifestyle.
This concept fits into a broader strategy explained here: Build a Marathon Training Plan for Busy Professionals and Parents
As a coach, I have found that runners are often attracted to advanced training methods before fully maximizing the basics. They become interested in doubling before mastering consistency. They want more volume before developing sustainable recovery habits. They look for the next training upgrade before fully benefiting from the current one.
Understanding when double runs help—and when they do not—is one of the keys to making smart long-term training decisions.
What You Need to Know First
Before discussing the benefits of double runs, it is important to understand what they actually are.
A double run simply means completing two separate running sessions on the same day. For example, a runner may complete an easy forty-five minute run in the morning and a second easy thirty-minute run later in the evening.
Most successful double-run programs do not involve two hard workouts.
In fact, that would usually be a mistake.
The majority of double runs are built around easy aerobic running. The objective is not to make the day harder. The objective is to increase total training volume while reducing the stress associated with one longer session.
Consider two runners trying to complete sixteen kilometres in a day.
One runner completes a single sixteen-kilometre run.
The other completes ten kilometres in the morning and six kilometres in the evening.
The total volume is identical, but the training stress is distributed differently.
This distinction becomes increasingly important as mileage grows.
For many experienced runners, double runs are less about intensity and more about workload management.
The ability to distribute training stress can sometimes make higher mileage more sustainable.
That said, sustainability depends on more than mileage alone. Recovery, sleep, nutrition, work demands, family responsibilities, and overall life stress all influence whether a second run becomes productive or problematic.
This is why there is no universal mileage threshold where every runner should automatically begin doubling.
The decision must always be viewed within the larger context of the athlete.
For a deeper understanding of how training volume fits into an overall marathon plan, Building a Marathon Plan provides the foundation behind these decisions.
The Potential Benefits of Double Runs
One of the biggest advantages of double runs is the ability to increase weekly mileage without dramatically increasing the stress of individual sessions.
As runners progress, long single runs can become increasingly demanding. A runner attempting to move from eighty kilometres per week to one hundred kilometres per week may find that extending every run creates excessive fatigue.
A second easy run can provide another option.
Instead of adding distance to already demanding sessions, the runner distributes some of the volume into shorter runs that are often easier to recover from.
This approach can also benefit runners preparing for ultramarathons. Many ultramarathon athletes use double runs to simulate accumulated fatigue without constantly performing extremely long sessions. The body learns to run while carrying moderate fatigue, which is a useful skill during longer races.
Another benefit is the increased frequency of aerobic stimulus. Every easy run provides an opportunity to reinforce aerobic development. More frequent exposure to easy running can help strengthen the aerobic system without requiring excessive intensity.
This is one reason elite runners often perform a large amount of seemingly easy mileage. The cumulative effect of consistent aerobic work becomes incredibly powerful over time.
There is also a practical consideration.
Some runners simply recover better from two shorter runs than one very long run. Their legs remain fresher, overall stress is lower, and training consistency improves.
The key is understanding that these benefits generally appear after the athlete has already developed a strong foundation of consistent training.
Double runs are usually a progression.
Not a shortcut.
Why Most Runners Don't Need Them Yet
This may sound surprising, but most marathon runners do not currently need double runs.
Not because double runs are ineffective.
Because other opportunities for improvement usually provide a greater return on investment.
Many runners can still improve substantially through better consistency, better recovery, improved nutrition, smarter pacing, and more structured training progression. These fundamentals often create larger performance gains than simply adding a second run.
One coaching observation I have made repeatedly is that runners tend to underestimate the power of doing the basics exceptionally well.
It is much easier to become excited about a new training strategy than it is to consistently sleep eight hours, execute easy runs properly, and follow a training plan month after month.
Yet those fundamentals are often what produce the biggest improvements.
This is one reason I rarely recommend double runs to runners who are still building consistency.
The first objective should be mastering one run per day.
Once that process becomes sustainable, the conversation about doubling becomes much more productive.
This connects closely with: How To Adjust Your Marathon Training Plan When Life Gets Busy
Who Should Consider Double Runs?
While most runners do not need double runs immediately, there are situations where they can become a valuable training tool.
The first group includes experienced marathon runners who have already established strong consistency and are struggling to increase weekly mileage through single runs alone. These athletes often reach a point where extending every run becomes impractical or excessively fatiguing. Splitting volume into two sessions may allow them to continue progressing while maintaining better recovery.
The second group includes ultramarathon runners preparing for longer events. Ultramarathon racing places unique demands on the body, and double runs can provide additional aerobic volume while helping athletes learn to run with accumulated fatigue. Instead of performing extremely long training sessions every weekend, some athletes can achieve similar benefits by distributing training stress more intelligently throughout the week.
A third group includes runners whose schedules actually make double runs more practical than single long sessions. A busy professional may struggle to find a continuous ninety-minute block during the day but have access to forty-five minutes in the morning and another thirty minutes in the evening. In these situations, double runs can be a useful logistical solution.
The common thread among these athletes is that they have already mastered the fundamentals. They are consistent. They recover well. They understand their training load. The second run becomes a tool that supports an already successful process rather than an attempt to compensate for weaknesses elsewhere.
Common Mistakes When Adding a Second Run
One of the biggest mistakes runners make is adding a second run too early.
They see advanced athletes using double runs and assume it must be the next logical step in their own development. Unfortunately, training progression does not always work that way. Just because a method is effective does not mean it is appropriate right now.
A second common mistake is turning both runs into workouts.
Insight
They struggle because their footwear is not aligned with their workload.
Guide Here
Most successful double-run systems rely heavily on easy running. The purpose is to increase volume, not intensity. When runners begin adding hard efforts to both sessions, fatigue often accumulates much faster than adaptation.
Another mistake is ignoring recovery.
Adding a second run increases training stress, even when both runs are easy. Sleep quality, nutrition, hydration, and life stress suddenly become even more important. Runners who fail to account for these factors frequently discover that the additional volume produces diminishing returns.
Finally, some athletes add double runs because they feel guilty about missing training opportunities. Instead of responding to a missed workout by calmly returning to the plan, they attempt to "catch up" by squeezing additional runs into the schedule. This approach often creates more fatigue than fitness.
Successful double runs are planned.
They are rarely emotional decisions.
The Difference Between More Training and Better Training
One of the most valuable lessons endurance athletes eventually learn is that more training and better training are not always the same thing.
This distinction becomes increasingly important as runners gain experience.
During the early stages of development, additional training often produces obvious improvements. More mileage creates more aerobic fitness. More consistency creates better results. The relationship appears straightforward.
Eventually, however, progress becomes more nuanced.
At that point, the quality of training decisions often matters more than the quantity of training itself.
Adding a second run may be beneficial for one athlete because it helps distribute training stress more effectively. The exact same change may be harmful for another athlete because recovery capacity is already stretched to its limit.
This is one reason coaching becomes increasingly individualized as athletes become more experienced. The best training decision is rarely determined by what another runner is doing. It is determined by what allows the individual athlete to continue improving while remaining healthy and motivated.
The goal is not to train as much as possible.
The goal is to train as effectively as possible.
If you're considering increasing your training volume, remember that volume is only valuable when your body can recover from it. Before adding a second run, it may be helpful to read Why Consistency Beats Hero Workouts in Marathon Training. In many cases, improving consistency provides greater benefits than adding more complexity.
Practical Tips for Runners
The first step is to evaluate whether you have already maximized the benefits of your current training structure. If consistency, recovery, nutrition, or sleep remain inconsistent, addressing those areas will usually provide a greater return than adding a second run.
Second, if you decide to experiment with double runs, start conservatively. One double-run day per week is often enough to evaluate how your body responds. There is no need to transform your entire schedule overnight.
Third, keep both runs easy initially. The objective is to introduce additional volume without dramatically increasing fatigue. Let your body adapt before considering more advanced applications.
Finally, monitor recovery honestly. If the second run consistently improves training quality and overall volume, it may be beneficial. If it creates persistent fatigue, declining workout quality, or reduced motivation, it may not be the right tool at this stage of your development.
Next, learn how this affects: Part 4-4: Recovery Techniques Post-Marathon
A Coach's Perspective
One of the reasons I like discussing double runs is that they reveal how runners think about training.
Many athletes assume the next breakthrough must come from doing more. More mileage. More workouts. More complexity. Sometimes that is true, but often the larger opportunity lies elsewhere.
I have coached athletes who improved dramatically without ever using double runs. What changed was not volume but consistency, recovery, pacing discipline, or training structure. Once those fundamentals improved, performance improved as well.
Mac Dewar's progression provides a good example of this principle. His success was not built on constantly searching for advanced training methods. It was built on structure, consistency, and a willingness to trust the process over time. Training progressed when it made sense. Workload increased when the foundation supported it. Each step built logically upon the previous one.
That approach is often less exciting than chasing advanced techniques, but it is remarkably effective.
I have also seen runners add double runs prematurely because they believed more training automatically meant more improvement. In many cases, the result was increased fatigue without meaningful performance gains. The issue was not the second run itself. The issue was that the athlete had not yet maximized the basics.
This is why I encourage runners to view double runs as a tool rather than a milestone.
You do not earn a second run because you have reached a certain level.
You use a second run when it serves a specific purpose.
That distinction may seem subtle, but it often determines whether the strategy becomes productive or problematic.
Final Thoughts
Running twice per day can be a valuable training tool.
For the right athlete, at the right time, and for the right reasons, double runs can increase training volume, improve aerobic development, and support long-term performance.
At the same time, they are not a requirement for marathon success.
Many runners achieve outstanding results without ever performing a single double-run day. What matters most is not whether you run twice per day. What matters is whether your training remains consistent, sustainable, and aligned with your goals.
Before asking whether you should add a second run, consider a different question:
Have you already maximized the fundamentals?
If the answer is no, that is probably where the greatest opportunity lies.
If the answer is yes, then double runs may become a useful tool within a larger training strategy.
As with most aspects of endurance training, success comes not from blindly doing more but from understanding why you are doing it in the first place.
If you'd like to continue exploring how training volume and recovery interact, the next logical step is reading How to Structure Recovery Weeks Without Losing Fitness. Understanding how recovery supports adaptation is essential before increasing workload.
