Many triathlons involve swimming in open water, such as freshwater lakes or saltwater oceans. Both bring their share of advantages and disadvantages. You should familiarize yourself with the type of water you'll be swimming in, so you can be knowledgeable about any special techniques you might need to use during the swim itself.
Buoyancy
The buoyancy of saltwater, such as in ocean swimming, is greater than the buoyancy of freshwater. Essentially, this means that your body floats easier in saltwater. Because of this, you'll be able to swim faster in a saltwater triathlon leg. You'll also have to kick less to keep your legs up, resulting in your being able to conserve more energy during the race than if you were swimming in a lake or river.
Lack of Grip
The more motion in the water, the less grip you'll have as you're swimming. This is especially true at the beginning of the swimming portion of a triathlon, when you can be caught in a mass of swimmers who are all moving at different speeds in close proximity. In saltwater, the ever-moving ocean and large waves can also increase this problem. When you have less grip, this means that the pressure you feel when you move your arms is unsteady. You may feel like the water is falling away from you as you swim, and that you have to use more effort to move forward. Ross Sanders, chair of Sports Science at the University of Edinburgh, compares this to the feeling you get when you're walking up a sandy hill.
Chaffing
Chaffing is a problem both while you're swimming and after you're done. You can have chaffing problems anywhere that your swimsuit may rub against your skin. The greater the salt content of the water you're swimming in, the greater the chances that you'll have chaffing problems. In addition, the salt residue left on your skin can cause chaffing on your feet during the run and bike part of the triathlon. To avoid these problems, some competitors liberally apply anti-chaffing cream before a swim and add moisture powder to the shoes and socks they'll be wearing during the bike and race portions.
Currents
Both saltwater and freshwater swimming can bring problems with currents. When swimming in the ocean, you'll have to deal with waves splashing against you as you race. Although tempting, you shouldn't try to swim over a wave but under it to avoid being pulled by the wave. In freshwater, hidden currents can still be a problem. Even a river that looks calm might have fast-flowing water beneath it that you have to pull against while you're swimming. Before swimming in an open-water competition, make sure that you're strong enough to swim against the currents found in saltwater and freshwater.
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With features published by media such as Business Week and Fox News, Stephanie Dube Dwilson is an accomplished writer with a law degree and a master's in science and technology journalism. She has written for law firms, public relations and marketing agencies, science and technology websites, and business magazines.