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Triathlete’s Guide To Going From Pool To Open Water

Race day shouldn't be your first time swimming in open water! As the weather warms, use this guide to transfer your pool skills to open-water swimming practice without missing a beat.

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Triathlons are rarely held in a pool, and there are so many aspects of open-water swimming that cannot be mastered in a chlorinated rectangle. The old adage of “train as you race” somehow gets forgotten when it comes to swimming, and because of it, some triathletes find themselves in open water for the first time of the season (or ever) on race day. Don’t let that be the case for you! As the weather warms up, plan to head out and find some natural water.

Know Before You Go

A little homework and prep goes a long way when dealing with the open water. Before you dive in, do a quick safety check and confirm that you have all of the following:

  • A brightly colored cap or safer-swimmer buoy for visibility
  • A partner or group of other swimmers for safety
  • Permission to be swimming in that location 
  • Visual inspection of any dangers present (high waves/chop, boat traffic, strong currents, riptides, submerged rocks or trees, marine life, etc.) 
  • Proper swimwear: If the water is under 75 degrees F, a wetsuit and neoprene cap are good ideas, as you’ll be in the water longer than if you’re simply racing. iIf it’s under 60 degrees F, that wetsuit becomes a must-have, along with a neoprene cap and booties and/or gloves. Do not try swimming under 50 degrees F under any circumstances. On the opposite side of the spectrum, if the water is above 80 degrees F, a wetsuit can become an overheating liability, so consider going sans wetsuit or wearing a swim skin (if you plan to wear one in your race) or neoprene buoyancy shorts (these are not allowed in racing, but can be handy training). For more, check out this guide: What to Wear for Open-Water Swimming (Even When it’s Cold)
  • Goggles with a clear field of vision—if you have blurry/scratched goggles in the pool, it’s not a big deal; if you have them in the open water, you might be unable to see important sighting landmarks and/or hazards in the water
  • A plan for the workout and the course, and a safety plan for when you get tired or if you get a cramp

Your Pool-to-Open-Water Translation Station

Open-water swim training can be as variable and creative as pool workouts, and each session should have a purpose and focus. Sometimes, that purpose is to swim a long distance to build endurance and confidence. That is the easiest type of workout to translate to open water: Go for a long swim with either a preplanned stopping point, or use your GPS watch to determine when you are done. 

Unfortunately, too much slow swimming produces only more slow swimming. To build strength and speed in the water, use creativity to create intervals and workouts in the open water. Any pool workout can be “translated” to open-water swim training using the following techniques:

  • Convert distance to time: Determine your average 100 yard/meter pace from the pool. Calculate it from any timed swim like a 1K time trial or a fast 400 in practice, and then add 5-10 seconds for a lack of walls. (E.g., Joe swam 6:28 for a 400 in February, so his pool pace is 1:37 and his open water pace is 1:45). A rule of thumb is that this method is recommended for intervals 200 and above.
  • Convert distance to stroke count: How many strokes do you take across the pool. Choose an easy number to multiply and calculate your strokes for a 50, 75, 100, etc. (E.g., Joe takes 21 strokes across the pool but rounds that number to 20. In open water, he will take 40 strokes for a 50, 80 strokes for a 100, etc). Use this for your shorter intervals, under 200.
  • Create a known distance: Drop homemade buoys (see directions below) at set points to create an open water course. Use a GPS watch or on-shore measurements for accuracy. Make a 300 triangle with three buoys, or a 200 out-and-back with two buoys. (This method works best in shallow water, where the buoy’s weight is secure on the bottom.)
  • Adopt landmarks: Design a course with nature and man-made objects already in place. Measure the distance between two piers, boat docks, or distinct trees along shore. Find items that are close to 50, 100, and 200 meters apart. This is recommended for deep water and places with currents and/or tides.
  • Invent rest intervals: The most important part of a rest interval is that you actually rest and recover. Stand on the bottom if the water is shallow enough. Float on your back or tread water in deeper locations. Hold onto your safe-swimmer buoy (see below for details) or a boat dock like you would hang on the wall.

Pool-to-Open-Water Example Set

Here is one typical pool swim practice that has been converted to open water based on Joe’s time and stroke translations from above:

Warm Up:
Pool – 400 swim (OW – 7-minute swim)
Drill Set: 
Pool – 6 x 50 as 25 kick/25 drill @ 1:30 (OW – 6 x :30 kick/20 strokes of any drill w/:15 rest)

Main Set:
(3 reps of): 
Pool – 1 x 300 endurance swim @ 6:00, 3 x 100 strong effort @ 2:00 (OW – 1 x 5:15 endurance swim w/:45 rest, 3 x 80 strokes strong effort w/:15 rest)

Pool – 200 stroke drills (see below for drills that work in the open water)

Form First

Always spend a little time focused on stroke technique at the beginning of practice, even when training in open water. Modify drills that are commonly used in the pool and include some open-water specific drills. Single arm drill in open water can determine if both arms are moving you in a straight line. Take 20 strokes with your right arm only, then 20 with your left arm. Did you drift to the right or left of a distinct landmark? If so, check to see if either arm is crossing the centerline, or if one arm is making stronger strokes than the other.

Similarly, bilateral breathing is helpful to practice in open water so you can comfortably breathe away from the wind and waves. Many pool drills, like the fist drill, catch-up drill, fingertip drag drill, and 6-3-6 drill are easy to do for a predetermined stroke count. Choose 15, 20, or 25 strokes of each drill and rotate through your favorites. 

And finally, don’t forget to sight. One of the most common things we hear from swimmers the first time they head out in open water is how easy it is to get off-course. Use our How to Sight When Swimming in Open Water guide to practice this essential skill

RELATED: Dear Coach: What Are Your Go-To Open-Water Swim Drills?

Get Geared Up

Check out these three items to elevate your open-water training sessions:

Safe Swimmer Buoy

Multiple companies are making these brightly colored, inflatable devices that trail behind you for visibility in the open water. They are also designed to be held onto when the swimmer gets tired or needs a break. Most are also designed like a drybag, which allows you to keep your valuables (ie: car keys) safe while training. We like Zone3’s collection that includes a buoy with backpack straps, one with built-in hydration, and one with easy access to dry items.

On Course Open Water Goggles

These (not cheap) goggles have an accelerometer, electronic compass, and LED lights to keep you on course in the open water with much less sighting. Another (pricey) favorite high-tech open-water combo is the FORM heads-up display goggles paired with a compatible GPS watch.

Course Markers

Set up your own course to train efficiently in the open water. Search “yellow hop ball” on a shopping site, inflate the 15-18 inch ball, tie a rope between the built-in-handle and a weight, then drop it in the water. Voila, a homemade swim buoy that is cheap and easy to transport and setup.

A Wetsuit

If you’re going to be out in the open-water for over 30 minutes, including resting, drills, and more, you’ll likely need a wetsuit based on the water temperatures above. Even if you don’t race in a wetsuit, training in even moderately chilly open water can suck the energy out of you quickly. As an added bonus, the buoyancy in a wetsuit allows you to rest better between sets if there’s nothing to hang onto.

RELATED: What Matters (And What Doesn’t When Buying a Wetsuit

Good Goggles

As we said above, clear, crisp, unscratched goggles are actually a safety priority in the open water. If you can’t see well, you don’t be able to safely navigate—allowing for the potential to get badly off course or at the very least waste time training—or see possible hazards under and above the water. Better yet, get a new pair when you head out in the open water, and find ones with a very wide field of vision.

RELATED: Ask A Gear Guru: Which Type of Goggles Should I Wear Today?

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