How Much Faster Is Swimming with a Wetsuit? (Triathlon Guide)

Research published in the Journal of Science and Medicine in Sport found that wetsuits improve swim performance by 5–10% on average. For a typical age-group triathlete swimming 1,500 m in 30 minutes, that's a time saving of 1.5–3 minutes.

The speed gains vary by ability:

Slower swimmers (2:30+/100m pace): Up to 10-12% faster. Wetsuits correct the biggest inefficiency — sinking legs and hips — which is more pronounced in less experienced swimmers.

Average swimmers (1:45-2:15/100m): 5-8% faster. Still significant buoyancy benefits with less room for body position improvement.

Fast swimmers (under 1:30/100m): 3-5% faster. These athletes already have good body position, so the wetsuit mainly reduces drag through surface smoothness.

Over an Ironman swim (3.8 km), the time saving can be 4–8 minutes for the average age-group athlete. That's enormous — equivalent to months of swim training.

The speed gain comes from two main factors:

1. Buoyancy: Neoprene is buoyant — it lifts your body in the water. The biggest benefit is raising your hips and legs, creating a more horizontal (hydrodynamic) body position. Poor body position is the single biggest speed limiter for most swimmers, and a wetsuit partially corrects it.

2. Reduced surface drag: Neoprene is smoother than skin. The suit creates a sleek, uniform surface that water flows over more easily. Premium wetsuits use special coatings (SCS — super composite skin) that further reduce drag.

A third, minor factor is warmth. Cold water causes blood vessels to constrict and muscles to tighten, reducing range of motion and power. A wetsuit maintains core temperature, keeping muscles functioning optimally.

Importantly, wetsuits do not help with propulsion — you still need to pull yourself through the water with proper technique. They reduce resistance and improve position, which makes your existing stroke more effective.

Triathlon wetsuits are designed differently from surfing or diving wetsuits. They prioritize arm flexibility for the swim stroke while maximizing buoyancy in the legs and core.

Wetsuit types:

• Full suit: Covers arms and legs. Maximum buoyancy and speed. Required when water is below 24.5°C (76°F) in most races.
• Sleeveless: No arm coverage. Easier to remove in transition. Slightly less speed benefit but more shoulder freedom. Allowed in warmer water.
• Two-piece: Separate top and bottom. Very easy transitions but less hydrodynamic. Rare in competitive racing.

Budget guide:

• Entry-level ($100-200): Basic neoprene, decent buoyancy, adequate for first races
• Mid-range ($200-400): Better flexibility panels, improved neoprene quality, good balance of price and performance
• Premium ($400-800+): Yamamoto neoprene, SCS coating, maximum flexibility and buoyancy, fastest suits available

For beginners, a mid-range wetsuit offers the best value. The speed difference between mid-range and premium suits is minimal compared to the difference between no wetsuit and any wetsuit.

A poorly fitting wetsuit negates most speed benefits and can actually make you slower:

Too loose: Water flushes through the suit, creating drag and reducing buoyancy. The suit balloons and catches water. This is the most common fitting mistake.

Too tight: Restricts breathing and shoulder movement. You'll fatigue faster and your stroke will shorten. Chest tightness amplifies swim anxiety.

The right fit: Snug everywhere with no air gaps or loose material. You should be able to raise your arms overhead with some resistance but without sharp restriction. The neck should be snug but not choking.

Sizing tips:

• Wetsuit sizes are based on height and weight, not clothing size
• Try the suit on dry (it's harder to put on than to swim in)
• You should feel slight compression across the chest and back
• Ensure the crotch sits high — if it's pulling down, the suit is too short
• Check for excess material behind the knees and at the lower back

Always test your wetsuit in the pool before race day. Swim for at least 20 minutes to assess comfort and range of motion.

A fast wetsuit removal can save 30–90 seconds in transition. Practice this:

Step 1: While running from the swim to T1, unzip the suit and pull it down to your waist. Start this immediately after exiting the water.

Step 2: At your transition spot, step on the suit with one foot and pull the other leg out. Repeat with the other side.

Step 3: Leave the suit on the ground (or toss it in your transition bag).

Pro tips:

• Apply Body Glide or cooking spray to your ankles and wrists before the race. The suit slides off much faster.
• Practice removal at least 5 times before race day
• Don't fight the suit — if it sticks, stay calm and wiggle rather than yanking
• Consider wearing speed cuffs — thin ankle and wrist covers that the suit slides over easily

Elite athletes remove their wetsuits in under 10 seconds. With practice, 20–30 seconds is achievable for age-groupers.

Race organizations have rules about wetsuit use based on water temperature:

Ironman: Wetsuits allowed below 24.5°C (76.1°F). Age-group athletes who wear wetsuits in water 24.5–28.8°C (76.1–83.8°F) can race but are ineligible for awards and Kona qualification. Above 28.8°C, no wetsuits.

World Triathlon: Wetsuits allowed below 22°C (71.6°F) for sprint/Olympic. Different rules for longer distances.

In warm-water races, you'll swim without a wetsuit. This is where swim technique becomes even more important — you can't rely on buoyancy to compensate for poor body position.

If you know your target race is warm-water, practice swimming without your wetsuit regularly. The difference in body position and speed can be surprising if you've only trained with a wetsuit.