Running requires several physical attributes: strong, endurance-trained muscles, strong joints and tendons, and a high lung capacity. When your lungs don't function well, you may experience breathing problems during exercise such as shortness of breath.
Athletes, especially runners, train their lungs to increase capacity and strength of the breathing muscles. Holding your breath underwater improves lung function, gives you a swimmer's lung capacity, which also helps running ability.
Holding your breath under water can increase your lung strength and capacity.
Increased Lung Capacity
Holding your breath underwater causes you to increase your lung volume. According to Olympic.org synchronized swimmers are able to hold their breath under water for one minute. In a test taken to rank aerobic capacity just before the Olympic Games in London in 2012, it was discovered that synchronized swimmers came second to long-distance runners.
With underwater training, you can increase the amount of oxygen that your lungs can hold. Runners who similarly train may find that they breathe easier during runs and avoid feeling out of breath as much during an extended or high-intensity run.
Read more: How to Improve Lung Capacity for Running
Improved Diaphragm Control
The diaphragm is a muscle nestled immediately below your lungs that helps you inhale and exhale. Training in the water teaches you how to gain improved control over this muscle. When swimmers hold their breath underwater, the diaphragm may spasm, causing them to breathe heavily to regain their breath.
However, with training, you can learn to overcome and gain greater control over the diaphragm muscle. According to the National Heart, Lung and Blood Institute a "lung volume test" can accurately determine how much air your lungs can hold. Improving the strength and control of this muscle helps you to breathe more efficiently and also avoid gasping for breath.
Improving Lung Capacity Through Swimming
In addition to holding your breath underwater, swimming also improves lung function. Swimming.org recommends swimming breath control drills to better improve what they call your "aerobic turnover" — the amount of air you breathe in and out. Since humans normally expel only 75 percent of the air in their lungs, the rest sits at the bottom of your lungs stale.
The idea is to stand in the water and bend your legs until your chin touches the water. Inhale one deep breath and then lower down until your nose and mouth are below water. Excel slowly until you empty your lungs. Stand back up and inhale. Repeat this exercise six times.
This is just one of many underwater swimming techniques to improve your lung capacity as a swimmer. And runners may experience improved lung function by incorporating swimming and breathing drills into their training regimes.
Read more: 12 Essential Tips for New Runners
Always Take Caution
If you decide to hold your breath underwater, be aware of the dangers and risks involved. When not done carefully, you run the risk of drowning or causing tissue damage to the heart, brain and lungs. Depriving vital tissues of oxygen for an extended period may be dangerous.
Starting off slowly helps your body adjust to decreased oxygen intake, especially if you have trouble breathing while swimming. Also, having another person present while you're underwater decreases your overall risk of passing out or drowning in the pool.