Why Does Swimming Make You Sleepy? 15 Reasons
Feeling drowsy after a swim is very common, for children and adults. Most of the reasons are harmless, and some are signs of a good workout.
The effort
1. Swimming uses the whole body
Arms, legs, back and core all work at once, so even a moderate swim is real exercise.
2. Water resists every movement
Water is much denser than air, so every stroke and kick takes effort.
3. Beginners work harder
When technique is still developing, you use more energy to cover the same distance. Fatigue drops as you become more efficient.
4. Breathing is controlled
You can only breathe at certain points in the stroke, which makes swimming feel more demanding than the same effort on land.
5. New learners use their brains too
Concentrating hard on new skills is mentally tiring, especially for children in lessons.
The environment
6. Your body regulates its temperature
Pool water is cooler than your body. Cooling in the water and warming up again afterwards both take energy.
7. Sun and heat
Most public pools in Singapore are outdoors. Time in the sun and heat adds to tiredness. Use shade and sun protection.
8. You sweat without noticing
Even in water you lose fluid through sweat. Mild dehydration can make you feel tired. Drink water before and after.
9. Low blood sugar
Swimming on an empty stomach, or a long session without a snack, can leave you drained. See why swimming makes you hungry.
The relaxation
10. Steady rhythm
The repetitive strokes and breathing are calming for many people.
11. Slow exhales
Breathing out slowly underwater is similar to relaxation breathing techniques.
12. Stress relief
Many people feel calmer after swimming, which can feel like sleepiness. See swimming and mental health.
13. A warm shower afterwards
A warm shower and getting into dry clothes after cooling down in the pool is very relaxing.
Timing
14. Evening swims
An evening swim followed by dinner naturally leads into rest.
15. Children's routines
Children often nap or sleep well after lessons. Many parents schedule lessons with this in mind. Read does swimming improve sleep?
When to check with a doctor
Feeling pleasantly tired is normal. But see a doctor if you feel unusually exhausted, dizzy, breathless or unwell after swimming, or if tiredness lasts for days. Also, never swim alone if you feel very drowsy, for example after taking medication that causes drowsiness.
Swim more efficiently
Better technique means less wasted effort. See our swimming tips for beginners, or our adult and kids swimming courses.
More in health and wellbeing
- Does swimming improve sleep?What the evidence says for adults and kids
- 5 swim workouts for runnersRecovery, endurance and pool running
- 14 swim workouts for triathletesTechnique, endurance, race pace and open-water skills
- 20 swimming cool-down exercisesIn-pool and dry-land
Further reading
- World Health Organization, Physical activity fact sheet. How much activity adults and children need each week.
- National Environment Agency, Lightning safety poster. Leave the water during thunderstorms and wait 30 minutes after the last thunder.
Want to swim with less effort?
Tell us the learner's age, their swimming experience and anything the instructor should know. We will suggest a suitable course, format and pool. Lessons run at public swimming complexes, private venues and condominium pools across Singapore.