Open Water Swimming: Complete Guide to Technique, Safety and Training

In this article

Open water swimming combines endurance, technique and navigation in an environment that is constantly changing.

Unlike pool swimming, there are no lane ropes, walls or black lines to guide you. Wind can create waves, currents can move you away from your intended line, visibility may be limited and the water temperature can change how your body responds.

These differences make open water swimming more demanding, but they are also what make it rewarding. Lakes, rivers and oceans allow swimmers to cover continuous distances, explore natural environments and prepare for triathlon events without turning at the end of every pool length.

Effective open water swimming is not simply about swimming harder. It requires the ability to remain relaxed, breathe in changing conditions, navigate efficiently, assess risk and adapt your technique to the water.

This complete guide explains open water swimming safety, equipment, wetsuits, breathing, sighting, drafting, race starts, cold water, training sessions and common mistakes.

Key takeaways

Open water swimming requires navigation and environmental awareness in addition to normal swimming technique.
Never treat a lake, river or ocean like a controlled swimming pool.
Check the weather, water conditions, local rules, water quality and entry and exit points before swimming.
Swim with other people or at a supervised open water venue rather than swimming alone.
A brightly coloured swim cap and tow float help other water users see you.
Enter cold water gradually and allow your breathing to settle before beginning the main swim.
Sighting regularly helps you swim a shorter and more accurate route.
Breathing comfortably to either side gives you more options when facing waves, sunlight or other swimmers.
A well-fitted swimming wetsuit provides warmth, buoyancy and a more streamlined body position.
Pool training remains valuable, but important open water skills must eventually be practised in a suitable outdoor environment.

What is open water swimming?

Open water swimming means swimming outside a conventional swimming pool. It can take place in:

Lakes
Reservoirs
Rivers
Canals
Coastal waters
Oceans
Designated outdoor swimming venues

The term covers several different activities. One swimmer may enter a lake for a relaxed recreational swim, while another may be training for a 1.9 km Half Ironman swim or competing in a long-distance open water race.

Open water distances also vary considerably. A short training session may involve several controlled loops close to shore, while marathon swimming events can extend far beyond standard triathlon distances.

Triathlon commonly uses open water for the first discipline. Standard race distances include:

750 m in a sprint triathlon
1.5 km in an Olympic-distance triathlon
1.9 km in a Half Ironman or IRONMAN 70.3
3.8 km in a full-distance Ironman

You can compare these formats in our complete guide to triathlon distances from sprint to Ironman .

Open water swimming vs pool swimming

Fitness developed in a swimming pool transfers to open water, but the two environments are not identical.

Pool swimming	Open water swimming
Controlled water temperature	Temperature changes with location, weather and season
Clear lane markings	Navigation requires sighting and external landmarks
Walls provide regular rests and push-offs	Swimming is continuous without turns
Usually calm water	May include waves, chop, current and tides
Known depth and controlled entry	Depth and entry conditions can vary
High underwater visibility	Visibility may be limited or almost absent
Lane ropes separate swimmers	Swimmers may be close together during events
Lifeguards commonly present	Safety supervision depends on the venue

A swimmer who is comfortable covering 2,000 metres in a pool may initially find a shorter outdoor swim more difficult. The reason is not necessarily poor fitness. Cold water, limited visibility and unfamiliar surroundings can increase breathing rate and muscular tension.

Confidence normally improves as the environment becomes more familiar and the swimmer develops a reliable routine.

Open water swimming safety

Safety is the first priority in open water.

Outdoor water can contain risks that are not visible from the shore. These may include changing currents, submerged objects, boat traffic, steep banks, poor water quality and rapidly changing weather.

No single piece of equipment removes these risks. Safe swimming begins with selecting an appropriate location and making conservative decisions.

Use a recognised swimming location

A managed open water venue, organised group or lifeguarded location is generally preferable to entering unfamiliar water independently.

Recognised venues may provide:

Marked swimming routes
Known entry and exit points
Water quality information
Safety staff or lifeguards
Restrictions on boats and other water users
Local knowledge about weather and water conditions

Permission to swim should never be assumed. Reservoirs, harbours, rivers and privately owned lakes may prohibit swimming or require advance registration.

Do not swim alone

Swim with other people and remain aware of where the group is throughout the session.

Ideally, use a supervised venue or swim with an organised club. Someone on land should know where you are swimming, your intended route and when you expect to return.

A tow float improves visibility, but it should not be considered a replacement for appropriate supervision or a certified personal flotation device.

Check conditions before entering

Assess more than the air temperature. Check:

Water temperature
Wind direction and strength
Wave conditions
Tides and currents
Weather forecasts
Water quality alerts
Boat traffic
Local warning signs
Available entry and exit points

Conditions can change during a session. A route that initially feels sheltered may become difficult if wind or tide changes before the return journey.

Plan your exit before entering

Identify both your intended exit and at least one alternative.

A beach that is easy to enter may have rocks, waves or a strong current when you return. River banks can be steep, slippery or difficult to climb.

Keep the early part of an unfamiliar swim close to a safe exit rather than immediately travelling far from shore.

Make yourself visible

Wear a brightly coloured swimming cap rather than a dark cap that blends into the water.

A fluorescent tow float can make you easier to see from shore and by other water users. Visibility is particularly important where boats, paddleboards, kayaks or personal watercraft may be present.

Know when to stay out

Do not enter simply because the session was planned.

Stay out of the water when:

Conditions exceed your experience
Visibility is poor
There is thunder or lightning
Local authorities have issued a water quality warning
You cannot identify a safe exit
You are unwell, unusually fatigued or impaired
The venue is closed or swimming is prohibited

Turning around or cancelling a swim is a successful safety decision, not a failed training session.

Essential open water swimming equipment

The necessary equipment depends on temperature, location, distance and whether the session is recreational, competitive or part of a triathlon.

Equipment	Purpose	Priority
Swimming goggles	Provide visibility and protect the eyes	Essential
Bright swim cap	Improves visibility and provides limited warmth	Essential
Tow float	Improves visibility and may carry small items	Strongly recommended
Swimming wetsuit	Provides warmth, buoyancy and hydrodynamic benefits	Condition dependent
Neoprene cap	Provides additional head insulation	Useful in colder water
Neoprene gloves or socks	Provide additional protection for hands and feet	Condition dependent
Anti-chafing lubricant	Reduces friction around the neck and suit openings	Useful with a wetsuit
Swimming watch	Records time, distance, route and stroke data	Optional
Warm clothing	Supports rewarming immediately after the swim	Essential in cool conditions
Waterproof changing robe	Provides shelter while changing	Optional

Choosing open water swimming goggles

The best goggles provide a secure seal, clear visibility and a comfortable fit that remains reliable for the entire swim.

Lens choice should match the conditions:

Clear lenses: useful in low light, cloud or early-morning conditions
Tinted lenses: useful in moderate sunlight
Mirrored lenses: useful in bright conditions and strong glare
Polarised lenses: designed to reduce reflected glare from the water
Photochromic lenses: adjust to changing light conditions
Wide-field lenses: may improve peripheral awareness and make sighting easier

Goggles should be tested in training before an important event. A model that leaks or fogs repeatedly in open water is unlikely to improve on race day.

Many triathletes carry a second pair on race morning in case the primary goggles break or the weather changes.

Do you need a wetsuit for open water swimming?

A wetsuit is not required for every open water swim, but it can provide substantial benefits in cooler conditions.

A swimming wetsuit can:

Reduce heat loss
Increase buoyancy
Raise the legs and improve body position
Reduce hydrodynamic drag
Provide additional confidence in deep water
Offer limited protection from minor contact and stings

Use a wetsuit designed for swimming rather than a thick surfing suit. Swimming wetsuits generally offer greater shoulder flexibility and distribute buoyancy to support a streamlined position.

How should a swimming wetsuit fit?

The suit should feel close and secure without preventing normal breathing or restricting the shoulders.

Excess material around the lower back, chest or underarms can fill with water and increase drag. A suit that is too small may shorten the stroke and make relaxed breathing difficult.

Pull the suit gradually upward from the legs before inserting the arms. Enough material must reach the hips and torso before the shoulders are positioned.

Apply a suitable anti-chafing product around the neck and other friction points. Avoid products that may damage the wetsuit material.

Wetsuit rules in triathlon

Training decisions and race regulations are different. A wetsuit that feels appropriate during a personal swim may not be permitted in a particular event.

Current World Triathlon age-group rules generally make wetsuits mandatory at water temperatures of 15.9°C or below. For athletes through the 55–59 category, they are forbidden at 22°C and above for swims up to 1,500 metres and at 24.6°C and above for longer swims. The rules differ for older age groups.

Under the 2026 IRONMAN competition rules, age-group athletes may generally wear wetsuits in water temperatures up to and including 24.5°C. They are generally mandatory below 16°C.

These thresholds can be affected by event format, athlete category, air temperature and local race rules. Always use the current competition rules and the athlete guide for your specific event rather than relying on a general summary.

How to enter open water safely

Avoid diving or jumping into unfamiliar water.

Enter gradually using a known access point. This gives you time to assess the surface, depth, temperature and footing.

A controlled entry can follow this sequence:

Check the entry and exit from land.
Walk into the water gradually where conditions allow.
Allow water to reach the legs and torso.
Splash water onto the face and neck.
Place the face in the water and exhale slowly.
Begin with easy strokes close to the exit.
Wait for breathing to settle before increasing effort.

The first sensation of cold can create an involuntary gasp and rapid breathing. Starting an intense swim immediately can make that response harder to control.

Remain close to safety while evaluating how your body responds on the day.

Open water swimming technique

Efficient open water technique begins with the same foundations as efficient pool swimming:

A stable and streamlined body position
A controlled breathing pattern
An effective catch and pull
Relaxed recovery above the water
A sustainable kick
Minimal unnecessary movement

The difference is that open water technique must remain adaptable.

Your preferred pool stroke may need to change when facing waves, current, close contact or limited visibility.

Maintain a relaxed stroke

Tension increases energy expenditure and often makes breathing more difficult.

Keep the hands, jaw, neck and shoulders relaxed. Focus on completing each exhalation underwater rather than holding your breath between inhalations.

An open water race may begin quickly, but the majority of the swim should still feel controlled enough to maintain technique.

Adjust your stroke rate to the conditions

A long, slow stroke may work well in calm water. In waves or chop, a slightly higher stroke rate can help maintain momentum when the water interrupts the normal rhythm.

The objective is not to spin the arms as quickly as possible. It is to reduce long pauses where waves can stop forward movement.

Use a compact kick

Distance swimmers and triathletes commonly use a relatively economical kick. Its primary purposes are to support balance, maintain body position and connect the movement of the upper and lower body.

An excessively large kick can consume energy quickly, particularly when wearing a buoyant wetsuit.

However, additional kicking may be useful when:

Accelerating at the start
Moving around another swimmer
Approaching a turn buoy
Preparing to exit the water
Increasing blood flow to the legs before transition

Breathing in open water

Open water breathing must account for wind, waves, sunlight, nearby swimmers and changes in direction.

The fundamental technique remains the same: exhale while the face is underwater and inhale during the natural rotation of the body.

Holding your breath creates a rushed exchange when the mouth reaches the surface. This can contribute to a feeling of breathlessness even when the physical effort is moderate.

Should you breathe bilaterally?

You do not have to breathe every three strokes throughout an open water swim.

Many swimmers race effectively while breathing every two strokes to their preferred side. However, the ability to breathe comfortably to either side is extremely useful.

It allows you to:

Turn away from waves
Avoid direct sunlight
Watch nearby swimmers
Adapt when the course changes direction
Reduce dependence on one side

Practise both sides in training, even when your race breathing pattern remains primarily unilateral.

How to breathe in waves

When waves arrive consistently from one direction, breathe to the sheltered side where possible.

Rotate with the body rather than lifting the entire head. A slightly higher recovery and quicker inhalation may be necessary in rough water.

If a wave interrupts the breath, avoid immediately gasping. Return the face to the water, exhale and take the next available breath.

How to sight in open water

Sighting means briefly looking forward to confirm your direction.

It replaces the black line found at the bottom of a swimming pool and is one of the most important open water skills.

Poor navigation can cause a swimmer to cover considerably more than the official course distance. A fast swimming pace provides limited benefit when the route is unnecessarily long.

Basic sighting technique

Choose a large, visible object in the direction of travel.
Press down slightly with the leading arm.
Lift only the eyes and goggles above the surface.
Identify the landmark quickly.
Rotate to the side for a normal breath if required.
Return the head smoothly and continue swimming.

Avoid lifting the entire head and chest. This causes the hips and legs to sink, increasing resistance.

How often should you sight?

There is no universal sighting interval.

A practical starting range is approximately every six to twelve strokes. Adjust according to:

Wave conditions
Current
Visibility
Course shape
The size of the landmark
Your ability to swim straight

Sight more frequently near turns, during poor visibility or when crossing a current. Sight less frequently when following a clear line in calm conditions.

Use large landmarks

A race buoy may disappear behind waves or other swimmers.

Before starting, identify a larger object positioned behind or beyond the buoy, such as:

A building
A hill
A tree line
A crane
A distinctive part of the horizon

The larger object remains easier to see, while the buoy can be used for precise navigation as you get closer.

How to swim straight in open water

Most swimmers naturally drift to one side.

Common causes include:

A stronger pull on one side
Crossing the centre line during hand entry
Uneven body rotation
Breathing exclusively to one side
Poor sighting
Wind, waves or current

Improving stroke symmetry can reduce the problem, but no swimmer should rely entirely on feel. Regular sighting remains necessary.

During training, compare the direction you naturally travel when breathing to different sides. This can reveal whether the drift is environmental or related to your technique.

Drafting in open water swimming

Drafting means swimming close enough to another swimmer to benefit from the water movement they create.

It can reduce the energy required to maintain a given speed, making it valuable during triathlon and open water races.

Two common positions are:

Directly behind: swim near the other swimmer’s feet without repeatedly touching them
Beside the hips: position your head near the swimmer’s hip and use the lateral movement of the water

Drafting should remain controlled and considerate. Repeatedly hitting another swimmer’s feet is distracting and may cause them to move away or accelerate.

Do not follow blindly. The swimmer ahead may be navigating poorly. Continue sighting independently to confirm that the group is following an efficient line.

Open water turns and buoys

Turns can become congested because many swimmers attempt to take the shortest possible line around the same point.

Approaching slightly wider may be faster when it allows you to maintain rhythm and avoid contact.

A controlled turn can involve:

Sighting more frequently as the buoy approaches.
Identifying the next section of the course before reaching the turn.
Moving gradually toward your chosen line.
Using shorter strokes when space becomes limited.
Accelerating smoothly after completing the turn.

Some swimmers use a rollover turn in which they rotate partially onto the back while moving around the buoy. This can be effective but should be practised before using it in a crowded event.

Open water race starts

Open water and triathlon events use several start formats.

Start type	Description
Rolling start	Athletes enter gradually according to expected swim time
Wave start	Groups begin at separate scheduled times
Mass start	A large field begins simultaneously
Beach start	Athletes begin on land and run into the water
Deep-water start	Athletes tread water behind a start line

Choosing your starting position

Position yourself according to your realistic ability rather than your ideal swim time.

Faster swimmers should generally begin near the front. Less confident swimmers may prefer the side or rear of the group, where there is more space.

Starting too far forward can create unnecessary contact as faster athletes move past. Starting too far back may require swimming around people who are slower.

Control the first few minutes

Adrenaline and close contact make it easy to begin at an unsustainable pace.

Focus on:

Completing each exhalation
Keeping the stroke compact
Finding clear water
Avoiding unnecessary battles for position
Settling into a sustainable rhythm

A small amount of time lost at the start is preferable to spending the remainder of the swim trying to recover from panic or excessive effort.

Managing contact with other swimmers

Contact is common in mass-participation events and is not always intentional.

Hands may touch feet, arms may cross and swimmers may briefly move into the same space near a buoy.

When contact occurs:

Remain calm
Protect your breathing space
Move slightly to the side
Avoid responding aggressively
Resume your rhythm before increasing effort

Practising controlled group swimming can make race contact feel less surprising. This should take place in an appropriate environment with other swimmers who understand the session.

What to do if you panic in open water

Panic can affect both new and experienced swimmers.

Cold water, close contact, restricted breathing, poor visibility or an unexpectedly difficult start can create a rapid stress response.

Common signs include:

Uncontrolled breathing
A feeling that the wetsuit is too tight
Difficulty placing the face in the water
Loss of normal stroke rhythm
A strong urge to sprint or escape immediately

If panic begins:

Stop trying to maintain race pace.
Move away from other swimmers where possible.
Roll onto your back or adopt a supported floating position.
Concentrate on slowing the exhalation.
Orient yourself toward safety.
Signal clearly for assistance when needed.
Leave the water rather than forcing the session to continue.

Breaststroke can provide additional visibility, but it is not always enough when breathing remains uncontrolled.

There is no requirement to continue a training session or race when you do not feel safe.

Cold water swimming

Cold water changes breathing, circulation, coordination and heat loss.

Water can feel dramatically colder than air at the same temperature because it transfers heat away from the body more effectively.

Individual responses vary with:

Water temperature
Exposure duration
Body size and composition
Experience and acclimatisation
Wetsuit coverage
Wind and air temperature after exiting
Fatigue and health

A temperature that feels manageable to an experienced cold-water swimmer may be inappropriate for someone without similar exposure.

Enter gradually

Do not jump into cold and unfamiliar water.

Enter under control, remain close to the exit and allow the initial breathing response to settle before beginning to swim.

Keep cold-water sessions conservative

Do not base session length only on how comfortable you feel during the first few minutes.

Cooling can continue throughout the swim, and reduced coordination may make it harder to exit or change clothing.

End the session before you become significantly cold, confused, weak or unable to use your hands normally.

Prepare for the exit

Have warm, dry clothing ready before entering the water.

A simple post-swim setup may include:

A towel or changing robe
Dry base layers
A warm upper layer
A hat
Dry socks and shoes
A warm non-alcoholic drink

Remove wet clothing and rewarm gradually in a sheltered environment.

Swimming in waves, currents and tides

Moving water requires different decisions from a calm lake.

Waves and chop

Shorten the stroke slightly, maintain momentum and breathe away from incoming waves when possible.

Sight at the top of a wave rather than from the lowest point between waves. The elevated position can provide a clearer view of the course.

Currents

A current can move you sideways even when you are swimming directly toward your target.

Navigation may require aiming to one side of the destination so the current carries you toward the correct point.

Local knowledge is extremely important. Do not enter moving water without understanding the direction, strength and potential hazards.

Tides

Tidal conditions can change substantially during a swim.

Check local tide information and understand how the selected location behaves at different stages of the tide. Seek guidance from lifeguards, venue operators or experienced local swimmers.

Rip currents

Do not attempt to overpower a rip by swimming directly against it.

Remain calm, signal for assistance and follow local water-safety guidance. Depending on the situation, moving parallel to the shoreline may allow you to leave the current before returning toward land.

Open water swimming training

Effective training combines pool fitness with environment-specific practice.

The pool provides a controlled setting for improving technique and completing structured intervals. Open water develops navigation, confidence, continuous swimming and adaptation to real conditions.

Pool skills for open water swimming

Useful pool sessions can include:

Continuous swimming without long rests
Regular sighting practice
Breathing to both sides
Swimming behind another athlete
Swimming side by side
Short accelerations followed by controlled pace
Removing strong wall push-offs
Swimming several strokes with the eyes briefly closed
Practising a higher stroke rate

Eye-closing drills should only be performed in a controlled lane with sufficient space and supervision. Their purpose is to reveal whether you naturally drift, not to recreate the risks of open water.

Open water technique session

A technique-focused outdoor session could include:

Set	Purpose
5–10 minutes easy	Acclimatisation and relaxed breathing
6 × short sighting intervals	Practise lifting the eyes without dropping the legs
4 × controlled buoy turns	Develop navigation and acceleration
4 × drafting intervals	Practise following feet and swimming beside the hips
10–20 minutes steady	Continuous swimming and route control
Easy return to exit	Controlled completion and reorientation

Open water endurance session

An endurance session should remain within a safe marked area and match your current ability.

An example structure is:

10 minutes relaxed acclimatisation
3 × 8–15 minutes at sustainable endurance effort
One to two minutes of easy swimming between blocks
Short sections practising race effort
Easy swimming toward the exit

Time-based intervals are often easier to manage outdoors than attempting to measure precise distances.

Open water race-specific session

Triathletes can practise:

A controlled race start
Short accelerations to find space
Drafting
Sighting while maintaining pace
Several buoy turns
Increasing the kick before exiting
Removing the wetsuit immediately after the swim

Race simulations should not become uncontrolled mass-start practice. Use a small group, clear instructions and an appropriate supervised environment.

How far should you swim in open water?

Distance should be based on swimming ability, conditions, supervision and the purpose of the session.

A swimmer does not need to complete the full race distance during every open-water session.

Shorter sessions may be more productive when focusing on:

Sighting
Breathing
Starts
Drafting
Turns
Cold-water adaptation

Longer continuous swims can develop confidence and endurance, but they should be introduced gradually.

Pace calculations should account for navigation and conditions. Your outdoor pace may be faster in a buoyant wetsuit and calm water, or slower when facing waves, current and poor visibility.

Open water swimming for triathlon

Triathlon swimming differs from a standalone pool time trial.

The objective is not simply to reach the exit as quickly as possible. You must complete the swim with enough control to cycle and run effectively afterward.

A successful triathlon swim is:

Accurately navigated
Paced sustainably
Completed without unnecessary stress
Efficient enough to preserve energy
Followed by an organised transition

Pacing the swim

The first minutes may be faster because of positioning and adrenaline. Settle into a sustainable rhythm as soon as practical.

Avoid repeatedly accelerating unless needed to find clear water, stay with a suitable group or move around a buoy.

Your pace should reflect the total event. A 750 m sprint swim can be completed at a higher relative intensity than the 3.8 km swim at the beginning of an Ironman.

Preparing for a Half Ironman swim

A Half Ironman begins with a 1.9 km open water swim.

Athletes should be able to cover more than the race distance during normal training, but confidence in the environment is just as important as pool endurance.

Our guide to the Half Ironman swim, bike and run distances explains the complete 70.3 event.

Preparing for an Ironman swim

A 3.8 km Ironman swim requires sustainable technique and consistent navigation.

Small technical problems become more expensive over a longer distance. An inefficient line, restricted shoulders or poorly fitted goggles may cause significant difficulty over more than an hour of swimming.

Compare typical discipline splits in our analysis of the average Ironman time .

Exiting the water

Begin kicking slightly more during the final part of the swim to prepare the legs for standing and running.

Do not stand as soon as your hands touch the bottom. Continue swimming until the water is shallow enough to move efficiently.

When standing:

Expect temporary dizziness
Use support when available
Move under control
Lift the goggles only when it is safe
Begin opening the wetsuit while moving toward transition

Open water race-day checklist

Before leaving home

Check the weather and event updates
Pack two pairs of goggles
Pack the wetsuit and anti-chafing product
Bring warm clothing for before and after the swim
Review the course map
Confirm the start format
Check the official wetsuit decision procedure

At the venue

Locate the swim entry and exit
Identify each turn buoy
Choose large landmarks behind the buoys
Observe wind, waves and current
Listen to the safety briefing
Confirm your starting group

During the swim

Begin under control
Exhale continuously underwater
Sight according to the conditions
Use drafting without relying on another swimmer’s navigation
Stay aware of other athletes
Signal for help when necessary

Common open water swimming mistakes

Swimming alone

A calm and familiar location can still change unexpectedly. A tow float or watch cannot replace supervision and appropriate company.

Starting too fast

An aggressive start raises breathing rate and tension before a rhythm has been established.

Failing to acclimatise

Beginning hard immediately after entering cold water can make breathing more difficult to control.

Not practising sighting

Looking forward only during an event often causes the legs to sink and the stroke rhythm to break.

Following other swimmers blindly

A group can swim confidently in the wrong direction. Continue checking the course independently.

Using an unsuitable wetsuit

A poor fit can restrict the shoulders, cause chafing or fill with excess water.

Choosing the wrong goggles

Dark lenses may provide poor visibility on a cloudy morning, while clear lenses may be uncomfortable in direct sunlight.

Ignoring the return journey

Wind and current may assist the outward swim but make the return substantially harder.

Focusing only on distance

Covering more metres does not automatically improve navigation, group swimming or race-start skills.

Forcing a session in unsuitable conditions

Training consistency is not improved by taking unnecessary risks. Replace the session with a pool swim when the outdoor environment is inappropriate.

Frequently asked questions about open water swimming

Is open water swimming harder than pool swimming?

It can feel harder because of cold water, waves, limited visibility, navigation and the absence of walls. A wetsuit may improve buoyancy and speed, but the environment adds skills that are not required in a pool.

Is open water swimming safe?

It can be practised safely when conditions, supervision, location and individual ability are appropriate. It is not risk-free, and outdoor water should never be treated as a controlled pool.

Should you swim alone in open water?

No. Use a supervised venue, organised group or suitable swimming partner. Someone on land should also know your route and expected return time.

Do you need a wetsuit?

Not in every situation. The decision depends on temperature, duration, personal experience and local or competition rules. A wetsuit can provide warmth, buoyancy and improved body position.

Can you swim breaststroke in open water?

Yes. Breaststroke may help with orientation and recovery. However, a wide breaststroke kick can contact nearby swimmers in a crowded event, so remain aware of the space around you.

Which stroke is best for open water swimming?

Front crawl is generally the fastest and most efficient stroke for longer distances. Breaststroke and backstroke can still be useful for recovery, orientation and changing position.

How often should you sight?

Approximately every six to twelve strokes is a practical starting point. Sight more frequently when approaching turns or swimming in waves, current or poor visibility.

Why do I swim in a zigzag?

Common causes include an uneven pull, crossing the centre line, breathing to one side and insufficient sighting. Environmental factors such as current and wind may also move you sideways.

Why do I feel breathless in open water?

Cold water, anxiety, excessive starting speed and incomplete underwater exhalation can all contribute. Reduce effort, focus on a long exhalation and remain close to safety.

What is a tow float?

A tow float is a brightly coloured inflatable device attached around the waist. It improves visibility and some models include storage. It is not a replacement for a certified flotation device or proper supervision.

Can you rest during an open water swim?

Yes. You can float on your back, tread water or use an appropriate supported position. During an organised event, follow the specific rules regarding assistance and flotation devices.

How far should your first open water swim be?

Begin with a short, controlled session close to a safe exit. The purpose should be acclimatisation and confidence rather than achieving a particular distance.

Can pool swimmers immediately race in open water?

Strong pool fitness helps, but swimmers should first practise sighting, continuous swimming, group proximity, outdoor breathing and the relevant water conditions.

Are open water swim times slower than pool times?

They often are because navigation, waves and currents add difficulty. However, a well-fitted wetsuit, drafting and the absence of turns can sometimes make an outdoor pace surprisingly fast.

How do you avoid foggy goggles?

Use an appropriate anti-fog product, avoid touching the inside of the lenses and ensure the goggles fit correctly. Test the complete setup before race day.

What should you eat before open water swimming?

The appropriate meal depends on session duration and intensity. Avoid beginning a demanding swim immediately after a large meal, and arrive normally hydrated. Longer sessions and events require an individual nutrition plan.

Can open water swimming improve triathlon performance?

Yes. It develops navigation, confidence, environmental awareness, drafting and race-start skills that cannot be recreated completely in a pool.

What is a good open water swimming pace?

A good pace is one that remains sustainable while allowing accurate navigation and controlled breathing. Pace should be evaluated relative to distance, conditions, equipment and experience.

You can also compare broader finishing benchmarks in our guide to good triathlon times by distance and experience .

Final thoughts

Open water swimming requires more than pool fitness.

Strong outdoor swimmers combine efficient technique with navigation, environmental awareness and conservative decision-making. They understand when to sight, how to adapt breathing, how to use a wetsuit and when conditions make swimming inappropriate.

Begin each session by evaluating the location rather than assuming it is safe. Swim with others, remain visible and use a route that matches your ability and the conditions.

Technique improves through repetition. Sighting becomes smoother, contact feels less disruptive and deep water becomes more familiar. The objective is not to remove every challenge from open water, but to develop the skills needed to respond calmly and effectively.

Whether you are swimming recreationally, preparing for your first triathlon or training for an Ironman, consistency and good judgement are more valuable than forcing one long or difficult session.