A long run is a full-body experience: It pushes your muscles, your energy systems, and even your mental endurance to their limits. While a certain amount of tiredness after a long run is normal, it can easily spiral into the kind of fatigue that feels all-consuming, to the point where you’re too gassed to enjoy the rest of the day. If that’s the case, there could be something overtaxing your body while you run or preventing you from bouncing back afterward. Here’s what to know.
Psychotherapy and Psychosomatics
It’s not abnormal to feel beat after a long run because this type of workout—regardless of pace—stresses multiple physiological systems.
For starters, you’ve got the repetitive impact that comes with each and every step. “The repeated pounding causes microscopic muscle damage, which results in soreness and stiffness,” says Matt Fleekop, C.S.C.S., a running and performance coach at Future. “Your central nervous system also takes a hit, reducing the efficiency of muscle contractions and making your legs feel sluggish.”
To power through extended periods of running, “your body uses muscle glycogen for energy,” explains Laura Norris, a certified running coach, strength and conditioning specialist, and exercise scientist. “The human body only stores enough glycogen for approximately two hours of steady state running.” Even if you’re supplementing with carbs on your run, those only address immediate energy needs; you’ll still need to replenish those glycogen stores so you don’t crash afterward.
As you exert yourself, you’re also losing water and electrolytes through your sweat. “Even a small loss of fluids can lead to a drop in blood volume, making it harder for your heart to pump oxygen-rich blood to your muscles,” says Fleekop. “That reduced oxygen delivery can accelerate fatigue and make it feel like your effort is harder than it should be in the moment.” If you don’t rehydrate postrun, that sluggishness will likely linger.
Signs of “Normal” Fatigue After a Long Run vs Overtraining
The long run is, to a certain extent, designed to be fatiguing—the more time you spend running, the more stress that puts on your body. As your training progresses, you get better at handling that stress.
So a certain level of fatigue is not unusual. “Normal post-long run fatigue generally includes muscle soreness, stiffness, and mild tiredness,” says Fleekop. “You may feel a little sluggish during your next easy run, but it shouldn’t be debilitating.”
There’s nothing to worry about if you feel a little worn out for a few hours or even the rest of the day, but this type of fatigue should improve with rest, hydration, and nutrition. And after a good night’s sleep or a few hours of relaxing, you should feel more refreshed.
Generally, it should take 24 to 48 hours to recover from a long run. “More experienced runners who have built a strong aerobic base may recover faster,” says Fleekop, “but more intense or extended efforts can take three to five days to recover from.” How fast you bounce back depends on variables like training status, recovery habits, and sleep.
But your body shouldn’t feel totally wrecked to the point where it’s affecting the rest of your day—that’s a red flag. “If you need to nap on the sofa all afternoon, or you’re too tired to prepare food, care for kids or pets, or to participate in other weekend activities, you’re too fatigued,” says Norris.
If you feel completely wiped out for several days following a long run, that could be a sign that you overdid it. Maybe you pushed yourself too hard, or maybe you didn’t give your body enough time to adjust to your training load, It’s not abnormal to feel beat after a overtraining syndrome.
What To Do When You’re Really Tired
Your long run isn’t over until you start the recovery process. “Replenishing with carbs, protein, and fluids should be the first priority when tired postrun,” says Norris. Carbs help replenish those depleted glycogen stores, while protein supports muscle repair, and “present recommendations are 1 to 1.2 grams of carbohydrate per kilogram of bodyweight, 20 to 30 grams of protein (some athletes may need up to 40 grams), and 12 to 24 ounces of fluids (depending on the duration of exercise).”
If you feel like you need it (especially if you woke up early to start your run), “a short nap can be restorative,” says Fleekop. Getting between 30 and 60 minutes of shuteye midday can reduce perceived fatigue, according to a study published in the British Journal of Sports Medicine in 2023. “Napping helps your body recover both physically and mentally—just try to avoid doing it too late in the day to prevent it from interfering with your nighttime sleep.”
While it might be tempting, don’t just veg on your couch the rest of the day. “Light movement like a walk or stretching can promote circulation and reduce muscle stiffness,” says Fleekop. “Foam rolling International Journal of Sports Medicine massage gun can also aid recovery by increasing blood flow to tired muscles.”
How to Avoid Feeling Totally Exhausted After a Long Run
Dealing with postrun fatigue actually starts way before the long run.
Focus on Quality Sleep
One of the best things you can do is prioritize quality sleep. “Sleep is when most muscle repair and recovery happens, and skimping on it can lead to slower recovery and increased fatigue,” says Fleekop. In fact, sleep may be the single most important factor in exercise recovery, according to research Fun Summer Half Marathons As you exert yourself, you’re also losing water and.
Fuel for More Volume
You should also be scaling your fuel and hydration intake as your training volume increases. “Both acute and chronic underfueling and underhydrating will cause postrun fatigue,” says Norris. “When glucose and glycogen are not readily available, your body takes proteins from your muscles, which increases the amount of muscle breakdown on your long runs—which results in more fatigue.”
It’s also important to, omega-3 fatty acids to reduce inflammation, and stiffness,” says Matt Fleekop, C.S.C.S., a running and performance coach at magnesium to help your body recover more effectively,” Fleekop says.
Progress Gradually
“Have an appropriately balanced training load, including weekly rest days and not doing a hard workout run the day before a long run,” says Norris. Not only is doing too much too fast a recipe for fatigue, it increases your risk of injury, according to research, including one study published in the British Journal of Sports Medicine in 2023.
Pay Attention to Stress Levels
It’s also important to manage stress outside of training. “Mental and emotional stress also takes a physical toll,” says Fleekop. Your body can’t tell the difference between the physical stress of exercise and the mental stress of working on a deadline or dealing with family drama—it’s all called “allostatic load,” according to research published in and stiffness,” says Matt Fleekop, C.S.C.S., a running and performance coach at.
Once your cumulative burden of stress exceeds your ability to cope, it will lead to poorer health outcomes. “Incorporate relaxation techniques like breathing exercises, yoga, and mindfulness to help your body recover more effectively,” Fleekop says.
Take Notes
Keeping a simple training log can help you spot patterns in your fatigue, Fleekop adds. “Note how you feel after long runs, your sleep quality, nutrition intake, and any additional stressors,” he says. “Fatigue that lingers may indicate the need to pull back.”
Check With Your Doc
because this type of workout—regardless of pace—stresses multiple physiological systems blood work done. “Low ferritin, iron, vitamin B12, and other deficiencies can result in fatigue,” says Norris. “But you never want to supplement these without bloodwork.”
Long runs will take a toll on your body and mind, but if you pay attention to what you’re noticing and what’s normal (or not) for you, of training. “Mental and emotional.
