Open Water Triathlon Training

If you’re not in the know – a triathlon is an endurance multisport race including swimming, cycling and running. You may have unknowingly witnessed parts of such an event as you drove past scores of cyclists on a Sunday…

Triathlons are categorised by distance. They typically require a 750-metre swim, 20-kilometre bike ride and 5-kilometre run.

Swimming is often the most challenging, especially for new triathletes. Swimming technique can be a real slog to master, and combined with the challenging conditions of open water on race day, triathlon swims can feel pretty overwhelming.  

Triathletes spend hours in the pool practising the perfect stroke technique, but on race day, following buoys, and lines and trying to stay on course is equally important which is why training for an event outdoors as well as in indoor swimming pools is really important.

Swim Workouts for Triathlon Prep

Ideally, you might put in a few swims at your triathlon venue but, realistically, unless it is local, you will need to train at an open water swimming venue near to you – accessible at least once a week.  

If you are not an experienced cold-water swimmer we advise you not to take part in open-water triathlon events during the winter months.  You can learn more about winter swimming here – but it can be quite risky for the inexperienced.

Do you know how your body will react to cold water? How will your breathing and stroke need to be adapted? To feel at your most confident on the start line, it is important to have experienced open water swimming, before your triathlon event.

Find a Swim Training Partner

When swimming in open water, the best practice is to swim with a buddy. Draft in your favourite open-water swimmer and see if they want to do the triathlon together – or at least train together in the months leading up to the event.  

Having a buddy can help you swim straighter, as you’ll have someone to swim parallel to, like a lane rope. It’s also important to practise swimming next to someone to simulate race conditions where you need to maintain space between yourself and other athletes.

Do You Need To Swim Outdoors to Train For a Triathlon?

From the swimming pool to open water – what’s all the fuss about? Open water swimming is different to pool swimming in a number of ways.  Here are some things to be prepared for:

Cold Water

Very cold water can kill so it’s really important to not underestimate the impact it can have on your body. Experience of open water swimming in general as well as knowledge of cold water immersion and cold adaptation is needed to be able to do it safely. All of our winter swimmers have to be experienced open-water swimmers to swim with us after October.


Choppy water and blistering rain can really change how a swim feels – even for experienced athletes.


Just finding your stroke as you swim into a flock of ducks… it’s definitely not something you will have encountered at your local swimming baths.

Divers Cove Top Triathlon Tips

#1 Warm-up on the Shore

Just like any workout, a warmup will help prepare your body for the open water – a must-have if you want to achieve your best time in the swimming event. Stretching, jumping on the spot, or even a run along the shore will get your body warm and ready for the cool water.

#2 Make The Most Of Drafting

What is Drafting?

Drafting is a big part of open water swimming that you won’t experience in an indoor pool. 

It means to swim within another swimmer’s slipstream and allows the trailing swimmer to follow at a pace they couldn’t achieve on their own; or follow a swimmer of similar speed with greatly reduced effort. 

Sometimes it can be a real benefit, especially to preserve your legs for the bike and run elements of your triathlon or Ironman event.

#3 Cool Down Stretches

After your swim, make sure you warm down with some stretches to prevent soreness before moving on to your next event.

The Ideal Training Venue for Triathlons

Here at Divers Cove, Surrey our superb outdoor swimming venue has minimal currents and low weeds – this beautiful 7.3-acre reservoir, formerly used for sand extraction in Godstone is the ideal spot for triathlon training.  

If you are local to the Surrey area, are an experienced outdoor swimmer and are training for a triathlon this winter – come down to the Cove to train.  If you are thinking about signing up for a summer triathlon in 2023 then a summer membership with us may help you to be more prepared than simply training in your local indoor pool.

We are associated with the British Triathlon Federation (whose members are the Home Nation’s Associations of Triathlon England, Triathlon Scotland and Welsh Triathlon) 

Divers Cove will also be this year’s venue for Beyond Swim – a programme supported by Swim England which accredits open-water swimming venues.