Jim is an accomplished triathlete and endurance cyclist, and has raced in more than 35 USAT-certified races. He is also an avid trail runner and endurance gravel bike rider. Jim is a founder of Complete Tri and frequent writer on triathlon and cycling.
Around July or August of each year, many popular triathlons struggle with the question of whether they should allow wetsuits or not. We outline the recommended temps for using wetsuits in a different article, but in general water temps above 78 degrees are not very conducive to wetsuits. In some cases, using a wetsuit in water that is too warm can actually cause a swimmer to overheat which obviously defeats the entire point of using a wetsuit.
Who is the person who measures this water temp? Usually it is the race director for your particular race. You can also measure the temp with a simple kitchen thermometer, and some higher-end triathlon watches also have the ability to monitor the water temperature.
Lakes that are most prone to high water temps are those in the South as well as smaller lakes that might see greater temperature fluctuations based on the past few days’ average temperatures. Larger bodies of water have a moderating effect on water temps, causing the water to stay cooler longer and only increase by a degree or two per week during hot weather. Smaller lakes, on the other hand, can fluctuate by three to four degrees in just a couple days with the right mix of weather.
Most race directors will try their best to forecast the water temps on race day, and let racers know well ahead of time if wetsuit will not be legal. In some cases, a “no wetsuit” decision will be a surprise to racers on the morning of the triathlon, something that doesn’t faze experienced swimmers but could catch newer swimmers who are relying on their wetsuit off guard. In many shorter races, many triathletes are indifferent to the question of wetsuits because the time saved by not taking a wetsuit off at T1 more than offsets any time lost in the water due to the lack of wetsuit.
So what to do if you find yourself signed up for a race that may not allow wetsuits? First, practice an open water swim without a wetsuit to show yourself that you are a fine open water swimmer with or without a wetsuit. Do this with someone else to add some safety peace of mind if you consider the wetsuit a security blanket. Second, remember that without a wetsuit, you will need to kick a bit more as you would in a pool. Your legs may have a tendency to drop in the water as they would not with a wetsuit. Finally, consider slowing down your pace just a bit, keeping in mind that your body may exert just a bit more effort without the wetsuit. Remember, in open water swimming, it is all about relaxing and finding your groove.
