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If you’ve ever found yourself in the second half of a long run debating whether you should cut it short, you’re not alone. Mounting fatigue has a way of inducing that internal discussion among many runners.
Making the right decision for you can be tricky. On the one hand, you’re already really tired, and you have several miles to go; won’t mindlessly sticking it out put you in a hole and compromise your upcoming training and racing? On the other hand, isn’t one of the main points of long runs to get used to keep on keeping on when the desire to stop strikes?
As with most matters in running, the best answer is “it depends.” Here are five things to consider when a long run isn’t going well.
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Are you having a specific bodily pain?
Discomfort—mild muscular fatigue or tightness, stomach distress, hot spots on your feet—is typical when you’re going long. These unpleasant sensations seldom merit changing your plan for the day.
A specific bodily pain is another matter. Sara Hall, the second fastest marathoner in U.S. history, says she cuts long runs short under only one condition—if she’s worried about an acute pain or tight spot that might become an injury if she runs through it.
A good rule of thumb here is to assess whether your troublesome spot is making you alter your running form. If so, being a disciplined runner in this instance means ending the run. Continuing with compromised form can not only lead to injury in the noticeable area, but also cause problems elsewhere from you compensating for the trouble spot.
If you don’t have a potentially injurious pain, why do you want to shorten this run?
Probably the most common reasons for considering cutting a long run short are that the run is a much greater mental struggle than it should be and that you feel much more tired than usual. All runners have days like these, thanks to the fact that we’re humans, not machines that can predictably perform the same at, say, 8 a.m. every Sunday.
“People only have so much willpower,” Mark Coogan, a member of the 1996 U.S. Olympic marathon team who now coaches the elite group New Balance Boston, tells Runner’s World. “Life circumstances are part of the training process, so you need to account for them.”
If your family or work life has been particularly stressful lately, a long run can be a good way to reboot mentally. But it can also seem like just another obligation, and slogging away to hit an arbitrary mileage goal for the day can further drain you psychologically. If the run you’re doing isn’t a crucial part of your training plan—more on that below—it’s probably not a good idea to spend lots of precious mental capital on it. Cut the run short, and don’t beat yourself up over doing so.
If you feel okay mentally, but physically worn down almost from the start, you’re probably best off cutting the run short, especially if you have an important race in the next week or two. If you don’t have a race you care about in the next week or two, first try slowing your pace. If doing so doesn’t help, and the run isn’t an especially important one, then it’s okay to go shorter than you planned.
After any of these scenarios, do two things. First, focus on maximizing recovery in the immediate aftermath of your run—consume carbs and protein within an hour of finishing, stay on top of rehydrating, and do some gentle stretching or walking later in the day. Take at least one more easy day than usual before your next challenging run.
Second, review your recent training. Have you upped your mileage and/or intensity lately? Was the long run too soon after a race or hard workout? Are you trying to train like you “should” even though your non-running life is currently extraordinarily stressful? Are you following a cookie-cutter training plan that might not mesh with how you recover after long and hard runs?
“My training plans are always written in pencil,” Sara Slattery, who placed fourth in the 10K at the 2008 Olympic Trials and is now the head men’s and women’s cross-country coach at Grand Canyon University in Phoenix, tells Runner’s World. “Each athlete is very different in how they can handle training.”
Elite runners constantly adjust their training, and you’re allowed to as well. You might be someone who does best with three easy days before your toughest sessions, or who thrives on doing long runs on something other than a once-a-week schedule.
What are you training for?
Long runs have a place in all training programs. As legendary coach Bill Squires put it, they put the tiger in the cat.
But prioritizing long runs depends on what you’re training for. If you’re getting ready for a marathon, they’re arguably the most important aspect of your buildup. If your focus this season is a 5K PR, not so much. Slattery and Coogan agree that, if you’re not getting ready for a half marathon or longer, the cut-it-short threshold is lower than if you’re training for a long race. Gutting out a two-hour run when you’re overly tired will likely detract from the harder sessions, like kilometer repeats at 5K pace, that specifically prepare you for shorter distances.
That’s not to say that marathoners should do all long runs as planned regardless of how they feel. “Almost all marathoners already know how to persevere,” Coogan points out.
You don’t need to always prove to yourself you’re not a quitter. In his prime, Coogan trained with some of the best runners in the world of that era, such as former marathon world record-holder Steve Jones. Their typical long runs were 20 to 22 miles. “But if they were tired, they would often just cut off and say, ‘I am only doing 15 today.’ It’s being smart and knowing your body,” Coogan says.
If you’re training for a marathon, what is the goal of this particular long run?
Long runs for marathoners have two main types—putting in time on your feet at an easy to moderate effort, and harder outings that incorporate stretches at around goal marathon pace, or sometimes even a little faster. If you’re struggling on the first kind—a just-get-in-the-work long run—see if backing off the pace helps.
“I will adjust the pace if I’m not feeling like I should sustain the pace I’m at and prioritize hitting the distance,” Hall says. “In my mind, the point of a long run is to go the full distance or time, so I would rather finish the full duration and slow the pace down or cut the next day short if I need more recovery.”
Slattery says that usually seeing long runs through is an important part of marathon prep. “That run often gives athletes confidence,” she says. That’s especially true if covering the 26.2 miles of the marathon, without regard to pace, is the main challenge of the event for you. Knowing that you repeatedly stuck it out in training despite the urge to call it a day is a powerful psychological tool on race day.
If you’re struggling on a long run that calls for segments at marathon race pace, consider changing the run to a standard long run. Marathon pace should feel challenging, but not go-to-the-well hard. (If you track heart rate when you run, you can easily determine if hitting marathon pace on a given day is more of an effort than it should be.)
In these situations, convert the run to a standard long run and get in the distance, emphasize recovery in its aftermath, and try the race-pace work on your next long run.
Is this bad run part of a pattern?
Again, you’re not a robot; everyone has random bad days. But if, say, half of your recent long runs have been struggles, your body is trying send you a message.
“If you are feeling that run down and feeling like you need to cut your runs short more than half the time, you may be overdoing it in training,” Slattery says. “You may need to adjust the distance or pace of your runs so you are recovering better and able to do the training consistently.”
Coogan suggests also looking outside your running.
“Your takeaway is that you are overdoing it somewhere else in your life, and you don’t have the willpower right now,” he says. “You will need to find out what is making you mentally tired and see if you can change your lifestyle somehow.”
Scott is a veteran running, fitness, and health journalist who has held senior editorial positions at Runner’s World and Running Times. Much of his writing translates sport science research and elite best practices into practical guidance for everyday athletes. He is the author or coauthor of several running books, including Running Is My Therapy, Advanced Marathoning, and Meb for Mortals. Scott has also written about running for Slate, The Atlantic, the Washington Post, and other members of the sedentary media. His lifetime running odometer is past 110,000 miles, but he’s as much in love as ever.
