# Buoyancy of human body **URL:** \ **Category:** Factual Questions\ **Created:** [March 16, 2000, 8:53pm UTC](https://boards.straightdope.com/t/buoyancy-of-human-body/8672 "2000-03-16T20:53:00Z")\ **Posts on this page:** 7\ **Page:** 1
**Author:** ![Sycorax](https://avatars.discourse-cdn.com/v4/letter/s/a4c791/32.png) [@Sycorax](https://boards.straightdope.com/u/Sycorax)\ **Post date:** [March 17, 2000, 6:31am UTC](https://boards.straightdope.com/t/buoyancy-of-human-body/8672/1 "2000-03-17T06:31:00Z")
While on vacation, I swam a lot. While diving (from a standing position in the pool), I swim underwater as far as I can, but I can’t stay down. Swimming only the width of the pool, I rose to the surface about a foot before reaching the other side. My SO swam the length of the pool underwater the whole way. He said females have more body fat, males more muscle mass,which is heavier, and therefore women are more buoyant. Makes sense to me. I’m about 15 lbs. overweight too. Any way I can stay under longer? Different swim stroke/kick? (I was doing the breast stroke) or do I just need to lose the fat and build muscle? ---
**Author:** ![Ursa\_Major](https://avatars.discourse-cdn.com/v4/letter/u/a88e57/32.png) [@Ursa\_Major](https://boards.straightdope.com/u/Ursa_Major)\ **Post date:** [March 17, 2000, 6:39am UTC](https://boards.straightdope.com/t/buoyancy-of-human-body/8672/2 "2000-03-17T06:39:00Z")
Don’t carry as much air in your lungs. Take several deep breaths before going underwater and slowly release the air as you are swimming. In other words, don’t hold your breath for the whole trip. ---
**Author:** ![obfusciatrist](https://avatars.discourse-cdn.com/v4/letter/o/4af34b/32.png) [@obfusciatrist](https://boards.straightdope.com/u/obfusciatrist)\ **Post date:** [March 17, 2000, 6:54am UTC](https://boards.straightdope.com/t/buoyancy-of-human-body/8672/3 "2000-03-17T06:54:00Z")
> [@](#): > > Any way I can stay under longer? Different swim stroke/kick? (I was doing the breast stroke) or do I just need to lose the fat and build muscle? When I dive I have this problem too (I’m much more than 15 pounds overweight). My cure is a really heavy weight belt. That’ll allow you to stay down as long as you like (though it won’t look too fashionable when you are just lounging around poolside). Obfus. ---
**Author:** ![Diver](https://avatars.discourse-cdn.com/v4/letter/d/858c86/32.png) [@Diver](https://boards.straightdope.com/u/Diver)\ **Post date:** [March 16, 2000, 8:53pm UTC](https://boards.straightdope.com/t/buoyancy-of-human-body/8672/4 "2000-03-16T20:53:00Z")
Besides the advice already given, note that you tend to swim where you look. If you look up you tend to arch your back slightly and plane up. Try looking at the bottom of the pool while you swim. ---
**Author:** ![siva](https://avatars.discourse-cdn.com/v4/letter/s/7c8e57/32.png) [@siva](https://boards.straightdope.com/u/siva)\ **Post date:** [March 16, 2000, 9:01pm UTC](https://boards.straightdope.com/t/buoyancy-of-human-body/8672/5 "2000-03-16T21:01:00Z")
Buoyancy has alot to do with anatomy. For example caucasians are more buoyant than african americans because of muscle density. Muscle density in african americans is higher than in caucasians therefore there is far less air pockets in the muscle mass–decreasing buoyancy ---
**Author:** ![manhattan](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/manhattan/32/7_2.png) [@manhattan](https://boards.straightdope.com/u/manhattan)\ **Post date:** [March 16, 2000, 10:49pm UTC](https://boards.straightdope.com/t/buoyancy-of-human-body/8672/6 "2000-03-16T22:49:00Z")
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**Author:** ![scr4](https://avatars.discourse-cdn.com/v4/letter/s/59ef9b/32.png) [@scr4](https://boards.straightdope.com/u/scr4)\ **Post date:** [March 17, 2000, 12:40am UTC](https://boards.straightdope.com/t/buoyancy-of-human-body/8672/7 "2000-03-17T00:40:00Z")
I’m male so I can’t say for sure, but I’d imagine it has more to do with how you swim. Human bodies, male or female, are buoyant. To stay underwater, you have to do the reverse of what airplanes and birds do - pick up enough speed, and shape your body so the flow of water pushes you downwards. I can’t just sit in a pool and will myself to sink to the bottom, but if I kick off the edge of the pool with enough speed I can stay underwater as long as I can hold my breath.