Why Do I Sink When I Swim?

'Why do I sink?' - that depressing question you keep asking yourself.  Summed up by the constant battle to keep your legs at the surface when all they want to do is go down.  It's all made worse when another swimmer glides effortlessly past you like a duck on a pond, without a care in the world! 

There is a very good reason why some of us sink and some of us float easily, and it's all down to our relative density.

'Relative Density' - The Real Reason We Sink

Why do I sink? Relative density - the real reason we sink when we swim.Relative density of a male and female in freshwater. Women float better than men!

A stick floats and a rock sinks. The stick floats because its density is less, relative to the density of the water.  The rock sinks because its density is far greater, relative to the density of the water.  

In human terms, our fat is the stick and our muscles are the rock.  Muscles are generally more dense than water and cause us to sink.  Fat is less dense than water, party because it contains oil, which floats on water.  Thus fat floats.  Those of us with a higher fat to muscle ratio will tend to float.  Yes that’s right, fat people float better than muscular people - generally speaking.  

(I’m using fat and muscle as examples to keep things simple.  It must be noted that our bones, organs, blood and all that stuff all contribute to the density of our body.) 

The average male has a density of 0.98g/cm3 and the average female 0.97g/cm3.  In general most human beings will float to a certain degree.  Most will have a small amount of the body staying above the water surface.  Females float better than males.  Both males and females float better in saltwater than in freshwater.  Very few adults can float horizontally in the water, yet most children can hold a star float in the horizontal position.

Other factors that effect floatation are:

  • The volume of air in the lungs
  • An individuals muscle to fat ratio
  • The shape of the individual and therefore the location of their centre of gravity

Why Do I Sink? - Top 5 Tips for Staying Afloat

  1. Breathe - learning how to slowly exhale into the water will build confidence and also help to relax your body.
  2. Glide - a gliding action through the water as you swim is key to relaxing and the momentum of a glide helps to remain at the water surface and prevent sinking.
  3. Submerge - learning how to submerge will help you learn how to float. Yes, holding your breath and slowly submerging underwater will help all areas of swimming.  Learning that your body does not sink like a stone, but actually sinks very slowly, will in turn teach you to relax as you move through the water.
  4. Relax - learn how to relax by practicing summering,  breathing at the right time and standing up mid swim. These three key elements will erase tension as you learn how your body moves and behaves in the water. 
  5. Improve Technique - moving through the water smoothly and with minimum effort is essential for the natural sinker to stay afloat.  Correct swimming technique is a must for moving smoothly through the water.  

Are You Ready To Swim the Extra Mile?

My book 'How To Float' contains all the answers to that common question: Why Do I Sink?   

How To Float as you swim - an ebook with tip tips and exercises

Inside you will find:

  • top tips on how to relax
  • breathing exercises
  • exercises to perfect your gliding
  • tips no how submerging will help

Download your copy now and before you know it, you will be swimming the extra mile at the surface! Click here for more details or simply click ADD TO CART below. 


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