Stay under water longer

Whether you’re snorkelling, swimming under the dock or hunting for that snagged fishing lure, it would be nice to be able to stay under water longer. Before growing gills like Kevin Costner in Waterworld, try these steps for spending more time with the fishes.
• Calm down. Close your eyes and breathe in through your nose and out through your mouth for 30 seconds. This will lower your pulse, which means you’ll need less oxygen and can go longer between breaths.
• Practise. Hold your breath and put just your face under water for short periods of time. Putting your face in the water or splashing cold water on your face helps trigger a breath-holding instinct. Plus, your body won’t be so shocked when you go for the big breath.
• Go for it. Take a deep breath, exhale as much as you can, and then take another very deep breath and go under water.
• Move as little as possible. The more your muscles work the faster you’ll burn through your air and the sooner you’ll need to surface.
• Exhale. When you first feel like exhaling don’t resist, just do it in small amounts.
• Get to the surface. If you need to breathe, come up for air.
WARNING: Do not take several deep breaths or hyperventilate before holding your breath. This depletes carbon dioxide levels in your body, messing with your body’s ability to know when it needs to get air. This can lead to potentially fatal shallow water blackout, where you pass out under water without warning. (It’s always a good idea to swim with a buddy.)