We are pleased to announce that as of March 4, 2025, an updated Rich Text Editor has been introduced in the MyFitnessPal Community. To learn more about the changes, please click here. We look forward to sharing this new feature with you!
Exhaustion after exercise

oliviaedwards121
Posts: 3 Member
Hey guys,
Just wondering if anyone could help me out- I’m an 18 year old female and I experience extreme tiredness after exercise. I have a good diet and I get a good amount of sleep. When I do cardio, I feel like I need to sleep straight after. If I go for a run in the morning, I’ll be struggling for a nap all day. If I do a workout at night, I’ll fall straight to sleep an hour earlier than usual and be exhausted - barely functioning (difficult to talk, difficult to keep eyes open, difficult to walk) the next day. The tiredness normally lasts about 24 hours and correlates with the intensity of my workout. Does anybody else experience this? Or know what this could be? Without exercise, I have heaps of energy.
Thanks!!
Just wondering if anyone could help me out- I’m an 18 year old female and I experience extreme tiredness after exercise. I have a good diet and I get a good amount of sleep. When I do cardio, I feel like I need to sleep straight after. If I go for a run in the morning, I’ll be struggling for a nap all day. If I do a workout at night, I’ll fall straight to sleep an hour earlier than usual and be exhausted - barely functioning (difficult to talk, difficult to keep eyes open, difficult to walk) the next day. The tiredness normally lasts about 24 hours and correlates with the intensity of my workout. Does anybody else experience this? Or know what this could be? Without exercise, I have heaps of energy.
Thanks!!
2
Replies
-
It could be that you're eating too few calories to support your exercise.11
-
You could be going too hard too soon. Try shortening the length or intensity of you workouts and build up more gradual ly.6
-
I have a similar problem. I need a nap after an exercise session. I've been like that for ages. I haven't figured out the reason except my body just doesn't have the energy, and there is no real solution. I don't have any real advice other than to experiment with various factors, maybe have a diary and rate your tiredness.0
-
There can be medical conditions. Solution=see doctor, explain symptoms, ask for tests, persist in looking for solution.
In the meanwhile examine caloric balance and intake around exercise as these by themselves could explain some of these symptoms
Is caloric balance close to maintenance, or is a large deficit being attempted?
Has sufficient energy been provided before and after the exercise or is there a large energy gap centered around the exercise?
One of my first MFP friends ended up in hospital after fainting during exercise due to her large energy gap, even though she was obese at the time...5 -
Anemia is another option to consider as well - I struggled with it for years! Or thyroid, or diet/calorie related, etc... several things to consider, some of which can only be confirmed or denied by a medical professional.5
-
Doctor.3
-
oliviaedwards121 wrote: »Hey guys,
Just wondering if anyone could help me out- I’m an 18 year old female and I experience extreme tiredness after exercise. I have a good diet and I get a good amount of sleep. When I do cardio, I feel like I need to sleep straight after. If I go for a run in the morning, I’ll be struggling for a nap all day. If I do a workout at night, I’ll fall straight to sleep an hour earlier than usual and be exhausted - barely functioning (difficult to talk, difficult to keep eyes open, difficult to walk) the next day. The tiredness normally lasts about 24 hours and correlates with the intensity of my workout. Does anybody else experience this? Or know what this could be? Without exercise, I have heaps of energy.
Thanks!!
This is normal. Dial back the intensity, find your sweet spot.2 -
it could be that you are going too hard too soon
it could be that you need more calories to support your new activity
it could be medical.
best bet. talk to your doctor.
i was having similar issues and ended up with a diagnosis with hypersomnia-like narcolepsy. and the exercise was aggravating it5 -
What are your stats?
Height, amount of weight you need to lose, calorie intake? Are you eating more on exercise days?4 -
cmriverside wrote: »What are your stats?
Height, amount of weight you need to lose, calorie intake? Are you eating more on exercise days?
Yes, this, and specifically - what percentage of the calories you earn from exercise are you eating back?
It's common for people to not realize the way MFP works is for exercise calories to be eaten and/or to set a too aggressive weekly weight loss goal.
This is the simplest explanation.
If your fatigue is not related to under-fueling, see your doctor - when my anemia is untreated, I have crippling fatigue.2 -
kshama2001 wrote: »cmriverside wrote: »What are your stats?
Height, amount of weight you need to lose, calorie intake? Are you eating more on exercise days?
Yes, this, and specifically - what percentage of the calories you earn from exercise are you eating back?
It's common for people to not realize the way MFP works is for exercise calories to be eaten and/or to set a too aggressive weekly weight loss goal.
This is the simplest explanation.
If your fatigue is not related to under-fueling, see your doctor - when my anemia is untreated, I have crippling fatigue.
I think I might be underfuelling myself - I’m 54.6 kg and 172cm - I realised that I might need to have a snack before/after a workout. My iron levels are also normally on the low side (literally if they are one point lower I’d be anaemic). At one point I was overestimating my caloric intake by a few hundred each day - then a friend told me I was eating significantly lower than what I expected. I used to workout on an empty stomach but now I’ll have a protein ball or some food before working out to keep me levels up.thanks for your advice
0 -
oliviaedwards121 wrote: »kshama2001 wrote: »cmriverside wrote: »What are your stats?
Height, amount of weight you need to lose, calorie intake? Are you eating more on exercise days?
Yes, this, and specifically - what percentage of the calories you earn from exercise are you eating back?
It's common for people to not realize the way MFP works is for exercise calories to be eaten and/or to set a too aggressive weekly weight loss goal.
This is the simplest explanation.
If your fatigue is not related to under-fueling, see your doctor - when my anemia is untreated, I have crippling fatigue.
I think I might be underfuelling myself - I’m 54.6 kg and 172cm - I realised that I might need to have a snack before/after a workout. My iron levels are also normally on the low side (literally if they are one point lower I’d be anaemic). At one point I was overestimating my caloric intake by a few hundred each day - then a friend told me I was eating significantly lower than what I expected. I used to workout on an empty stomach but now I’ll have a protein ball or some food before working out to keep me levels up.thanks for your advice
That’s why you’re exhausted. You’re underweight and not fueling your activity. Your body is telling you that’s not ok.
Eat more.9 -
Almost 5'8" and 120lb plus almost anemic. I think we know why you're exhausted. Eat more food. Vitamin c helps with iron absorption. I do seem to remember falling asleep after runs when I was first starting out. Fuel up and give yourself time to adjust to a new workout.5
-
I deal with this often - especially if I don’t do something particular for a while and go back to it full force (I work at a gym and we work out HARD). Just this past week, I was zonked out for two days after some serious circuit training. Finally got back to it yesterday and cut my session in half to ease back in. Take it slow. Give yourself breaks. Hydrate. Eat enough. Add minutes on and exercises in day by day.0
-
oliviaedwards121 wrote: »kshama2001 wrote: »cmriverside wrote: »What are your stats?
Height, amount of weight you need to lose, calorie intake? Are you eating more on exercise days?
Yes, this, and specifically - what percentage of the calories you earn from exercise are you eating back?
It's common for people to not realize the way MFP works is for exercise calories to be eaten and/or to set a too aggressive weekly weight loss goal.
This is the simplest explanation.
If your fatigue is not related to under-fueling, see your doctor - when my anemia is untreated, I have crippling fatigue.
I think I might be underfuelling myself - I’m 54.6 kg and 172cm - I realised that I might need to have a snack before/after a workout. My iron levels are also normally on the low side (literally if they are one point lower I’d be anaemic). At one point I was overestimating my caloric intake by a few hundred each day - then a friend told me I was eating significantly lower than what I expected. I used to workout on an empty stomach but now I’ll have a protein ball or some food before working out to keep me levels up.thanks for your advice
My pleasure
It does indeed sound like you are under-fueling. And you probably need more iron.
Also, you didn't answer this: what percentage of the calories you earn from exercise are you eating back?3 -
This used to happen to me and it was because I was under-fueling. I would go for a run and just hit a wall and then I would be exhausted all day. I needed not just more fuel, but specifically more carbs which I had been afraid of (this is when I was doing WW, not MFP). Once I ate more it solved the problem.1
This discussion has been closed.
Categories
- All Categories
- 1.4M Health, Wellness and Goals
- 394.4K Introduce Yourself
- 44K Getting Started
- 260.5K Health and Weight Loss
- 176.1K Food and Nutrition
- 47.5K Recipes
- 232.3K Fitness and Exercise
- 392 Sleep, Mindfulness and Overall Wellness
- 6.5K Goal: Maintaining Weight
- 8.5K Goal: Gaining Weight and Body Building
- 152.7K Motivation and Support
- 7.8K Challenges
- 1.3K Debate Club
- 96.3K Chit-Chat
- 2.5K Fun and Games
- 4K MyFitnessPal Information
- 23 News and Announcements
- 930 Feature Suggestions and Ideas
- 2.3K MyFitnessPal Tech Support Questions