How to Prepare for Long Distance Swims

The three key points

Long distances in open water became more and more popular recently. By long distance we mean more than 5 km. The longer the distance, the more it takes to get ready. In this article we assume you want to swim 25 km. We suggest that the preparation for such an event takes at least 28 weeks. The following aspects are addressed:

Training plan
Nutrition
A few tips if you swim in open water

Training plan

Novices

If you are a novice your goal is to finish. This program assumes that you have been swimming at least 6 km per week for several months. The preparation phase of 28 weeks should enable you to cover at least half the distance in a workout, i.e. 12-13 km, without major problems. Long distance workouts beginning with the 13th week on the one hand serve to improve endurance on the other you can check food and beverages for compatibility. The volume of the workouts increases during the program and has its maximum in weeks 23-25 (28-33 km).

If your race does not go over 25 km but e.g. 10 km, you can reduce the long distance workouts between weeks 17-25. Swim about 6 km instead of up to 13 km.

You may want to swim some or most of the workouts in the open water. If possible swim with other swimmers who prepare for long distance events. You can be somewhat flexible about the training plan given below. For instance, place the rest days and workouts at your own gusto during the week. However, do not change the amount of km per week much.

week 1-4: 3 workouts 3 km (total 9 km), 4 rest days. If you swim in the pool, if you like, you can split the total into sets of, say, 20 x 100 m, 5 x 400 m, or 2 x 1000 m. However, the breaks should not exceed 5-10 seconds when swimming short intervals, and 15-20 seconds when you swims long intervals. Otherwise the effect on endurance is minimized. Adjust swimming speed to 75% of maximum heart rate. This corresponds to just below the anaerobic threshold or maximum lactate steady state. The increase in volume should not exceed 10% per week.
week 5-8: 4 workouts 3 km (total 12 km), 3 rest days
week 9-12: 5 workouts 3 km (total 15 km), 2 rest days
week 13-16: 5 workouts 3 km, and 1 workout 5 km (total 20 km), 1 rest day
week 17-20: 5 workouts 3 km, 1 workout 7 km (total about 22 km), 1 rest day
week 21-22: 4 workouts 4 km, 1 rest day, 1 workout 10 km (total about 26 km), 1 rest day
week 23-24: 2 workouts 3 km, 1 workout 8km, 1 rest day, 2 workouts 3 km, 1 rest day, 1 workout 8 km (total 28 km)
week 25: 5 workouts 4 km, 1 rest day, 1 workout 13 km (total 33 km)
week 26: 1 rest day, 4 workouts 4 km, 1 rest day, 1 workout 8 km (total 24 km),
week 27: 5 workouts 3 km (total 20 km), 2 rest days in between as you like
week 28 with race: 3 workout 3 km, 1 rest day, the 2 days before the race just 1 km per day (total 11 km)

Advanced Swimmers

Advanced swimmers who, however, have no experience in long distance swimming can basically use the training plan shown above with the following differences:

Increase volume depending on training level and goals
Participate to 2-3 test races during preparation phase (5 or 10 km if possible)
Vary tempo: Split 4 km workout in 1 x 800 m, 2 x 400 m, 4 x 200 m, 8 x 100 m, 16 x 50 m, and increase tempo with decreasing swimming distance, and or decrease breaks (negative split).

Food and fluid replenishment

If the race lasts for more than one hour you have to drink and sooner or later to eat something.

What type of beverages are fine for you, you have to find out by trial and error. Start experimenting by drinking before and during workouts. We recommend sports drinks with carbohydrates and minerals [Rehydration for swimmers - drinking in swimming].

With respect to food you have to find out what your stomach can stand after 1-2 hours exercise. For a start try ripe bananas and energy bars.

A few tips to remember when you are going to swim in open water

It is not always the fastest swimmers that win open-water races, but the ones who swim the smartest race and have the most experience.
Wear a white or yellow swim cap to make you better visible for boats. Silicon caps insulate better from the cold. Earplugs can help you to better tolerate the cold.
Exercise swimming straight and how to navigate in the open water. Lift your head for navigation every 20-40 strokes as you are turning your body and head to breathe. You want to limit how many times you lift your head because your hips will drop and your neck will hurt. Swimming straight needs practise.
To be able to breathe equally well on both sides is a clear advantage when waves and wind hit you from one side or if someone is next to you.
Slop on some sunscreen and don't forget your lips.
If feasible don't swim alone (buddy system, companion boat, tell the lifeguards what you are doing).
Stay close to the shore.
Exercise in the open water even if the water is choppy.
Wear your goggles under your cap (swimming in crowd). Find a pair that is comfortable long before the race and buy a spare pair right away.
No jewelry when you race (start in crowd, chafing).
Put on vaseline at spots that tend to chafe, i.e. inside your arms, opposite side at your chest, neck, around swimsuit straps.
Learn the course, check the buoys, look for landmarks before the race. This is critical when swells and big surf hide the buoys (check course when on top of the swell).
Get out fast, have a fast start to limit contact with others. Settle into your pace after that.
If you can and if legal, hang on to a faster group or swimmer. However, be cautious, you might get stucked behind a slower swimmer.
Drink plenty of fluids right away in long races and start eating after 30-60 Minutes.
Enjoy your surroundings, embrace nature.

More information

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