# Why can't some people float? Canonical: https://zestasy.com/wiki/why-some-people-sink/ Section: Zestasy Wiki > Movement · Updated: 2026-10-14 · Publisher: Zestasy *Zestasy Wiki: our reference answers. Checked for facts and sources; less curated than the magazine.* Whether you float comes down to how your body's density compares with water's, how much air is in your lungs and where your weight sits compared with where the water pushes up. Every body is different, so some people bob up easily while others float lower with sinking legs, and that is completely normal. A full breath, a relaxed body, the head back and arms spread wide make floating easier for almost everyone. Every swimming pool has one. The person who lies back and drifts like a lilo, and the person next to them who lies back and slowly, gracefully, goes down feet first. If you are the second one, there is nothing wrong with you. Floating is physics, and physics treats bodies differently. ## The physics in plain words Archimedes' principle says that anything in water is pushed upwards by a force equal to the weight of the water it displaces. If your body weighs a little less than the water it pushes aside, you float. If it weighs a little more, you sink slowly. A swimming science bulletin from San Diego State University sets out what shifts the balance: - **Body composition.** Different tissues have different densities. Fat tends to float, while bone and muscle tend to sink slightly, so people with denser builds often float lower. - **Air in the lungs.** Breathing in adds buoyancy without adding weight. A full breath makes floating noticeably easier. - **Fresh or salt water.** Salt water is denser, so people float a little higher in the sea than in a pool or lake. None of these is a judgement. They are just different starting points. ## Why the legs sink Even people who float often find their legs drifting down. The same bulletin explains why: the point where the water pushes you up (roughly around the chest, because of the air in your lungs) is not the same as your body's balance point for weight. The body rotates until the two line up, which for many people means the legs sink and the body settles at an angle. That angle varies a lot from person to person. ## How to float more easily Whatever your build, a few things help: - **Breathe in fully and keep the air in,** taking small breaths at the top of your lungs rather than big exhales. Your chest is your buoyancy aid. - **Put your head back.** Ears in the water, eyes to the sky. Lifting your head to look at your feet makes your legs sink. - **Spread out.** Arms wide, above shoulder height if you can, and legs apart, like a starfish. Arms stretched beyond your head shift the balance towards your feet. - **Push your hips up gently,** as if a thread were lifting your belly button. - **Relax.** Tension makes the body stiff and heavy. Floating is one of the few things in life that improves when you try less hard. - **Accept a little sculling.** Gentle circling movements of the hands are completely normal for people who float low. - **Bend your knees** if your legs keep dropping; letting them hang at an angle can feel more stable than fighting to keep them flat. ## Practising Start in shallow water you can stand in, ideally with a friend or an instructor beside you. Try floating on your back with a noodle or a float under your neck or knees, then gradually take the support away. Practise both back and front floats; our guide to [getting comfortable with your face in the water](https://zestasy.com/wiki/face-in-the-water/) is useful for the front one. ## Why it matters Being able to float, or to stay up with minimal effort, is a calm, useful skill. Water-safety bodies teach floating for exactly this reason: the RLSS UK Water Safety Code advises that if you fall in or get tired, you should stay calm, lie back and float while you call for help. If your body does not float easily on its own, gentle sculling and [treading water](https://zestasy.com/wiki/treading-water/) do the same job. ## FAQ ### Is it bad if I can't float? Not at all. Lots of confident swimmers float low or need a little sculling to stay up. Swimming relies on technique and movement, not on floating effortlessly. ### Why do I float better in the sea? Salt water is denser than fresh water, so it pushes up a little more. Many people find the sea noticeably easier. ### Will I float better if I hold my breath? A full breath does help, because air in your lungs adds buoyancy. You still need to breathe, so take small top-up breaths rather than emptying your lungs completely. ### Can lessons help with floating? Yes. A swimming teacher can see exactly what is pulling you down, usually head position or tension, and give you a cue that works for your body. ## Sources - [San Diego State University, Swimming Science Bulletin 36: Floating](https://coachsci.sdsu.edu/swim/bullets/float36.htm) - [Wikipedia: Archimedes' principle](https://en.wikipedia.org/wiki/Archimedes%27_principle) - [Royal Life Saving Society UK: The Water Safety Code](https://www.rlss.org.uk/wsc) ## Related - [How do you tread water for longer without panicking?](https://zestasy.com/wiki/treading-water/) - [Is it worth learning to swim properly as an adult?](https://zestasy.com/movement/learning-to-swim-properly-as-an-adult/) - [How do you get comfortable putting your face in the water?](https://zestasy.com/wiki/face-in-the-water/) - [Which swimming stroke is easiest to learn?](https://zestasy.com/wiki/easiest-swimming-stroke/) - [How do you breathe properly when swimming front crawl?](https://zestasy.com/wiki/breathing-front-crawl/) - [All Movement answers in the Wiki](https://zestasy.com/wiki/#movement)