Wetsuit vs. Skin Swimming: The Complete Open-Water Attire Strategy Guide for Triathletes

In the swim leg of a triathlon, the wetsuit is a piece of equipment that can significantly impact performance. It can make you faster, warmer, and safer—but only if you know when to wear it, how to choose it, and how to use it. This article will take an in-depth look at the differences between wearing a wetsuit and swimming skin, helping you make the most informed decision.

The Core Advantages of a Wetsuit

1. Buoyancy Boost

The wetsuit’s biggest secret weapon isn’t warmth—it’s buoyancy. Neoprene has a lower density than water, allowing your body to sit higher and more horizontally in the water.

• Increased lower-body buoyancy: The biggest source of drag for most swimmers is sinking legs; a wetsuit can lift your legs 3-5 cm higher
• Reduced overall water resistance: The more horizontal your body, the less frontal drag you face
• Speed improvement: Studies show that wearing a wetsuit can improve swimming speed by an average of 5-10%

Speed Difference from Buoyancy

Athlete Level	Skin Swimming 100m Pace	Wetsuit 100m Pace	Difference
Elite Athlete	1:10	1:06-1:08	2-4 seconds
Advanced Athlete	1:30	1:22-1:26	4-8 seconds
Intermediate Athlete	1:50	1:38-1:44	6-12 seconds
Beginner Athlete	2:10	1:52-2:00	10-18 seconds

It’s worth noting that the less perfect your swimming technique, the greater the speed improvement you’ll gain from a wetsuit, because the wetsuit can “correct” many posture issues.

2. Thermal Insulation

Neoprene traps a thin film of water between your skin and the suit, which is heated by your body to form an insulating layer.

• 2mm thickness: Suitable for water temperatures of 20-24°C
• 3mm thickness: Suitable for water temperatures of 16-22°C
• 5mm thickness: Suitable for water temperatures of 12-18°C

3. Protection

• Prevents jellyfish stings
• Reduces the risk of being scratched by other athletes’ fingernails
• Provides additional UV protection

Disadvantages of a Wetsuit

1. Restricted Shoulder Movement

Even with the highest-end wetsuits, neoprene imposes a certain degree of restriction on the shoulders. During longer swims, this restriction can lead to:

• Reduced stroke length
• Faster shoulder fatigue
• Altered swimming posture (forcing technique adjustments)

2. Thermoregulation Issues

Wearing a wetsuit in warmer water can lead to:

• Elevated core body temperature
• Excessive sweating (you won’t notice it in the water, but you’ll feel the dehydration symptoms once on shore)
• Elevated heart rate
• Negative impact on the subsequent bike and run legs

3. Transition Time Cost

Removing a wetsuit takes time and practice:

• Skilled athletes: 15-30 seconds
• Average athletes: 30-60 seconds
• Untrained athletes: 1-3 minutes (or even longer)

Race Rules and Water Temperature Standards

World Triathlon Rules

Water Temperature	Regulation
Below 16°C	Wetsuit mandatory
16-21.9°C	Wetsuit permitted (age-group rankings count)
22-24.5°C	Wetsuit permitted (not eligible for age-group rankings)
Above 24.5°C	Wetsuit prohibited
Above 32°C	Swim leg cancelled

IRONMAN Rules

Water Temperature	Regulation
Below 15.9°C	Wetsuit mandatory
16-24.5°C	Wetsuit permitted (rankings count)
24.6-28.8°C	Wetsuit permitted (not eligible for age-group rankings)
Above 28.8°C	Wetsuit prohibited

The Reality of Races in Taiwan

Water temperatures around Taiwan’s coasts typically range between 22-30°C, so:

• Winter (Dec-Mar): Northern waters around 18-22°C, wetsuit permitted
• Spring/Autumn (Apr-May, Oct-Nov): Around 23-27°C, depends on the rules
• Summer (Jun-Sep): Around 27-30°C, most races prohibit wetsuits

How to Choose a Wetsuit

Triathlon-Specific vs. General Diving/Surfing Wetsuits

You absolutely must choose a triathlon-specific wetsuit. The differences are as follows:

Feature	Triathlon-Specific	General Water Sports
Shoulder Design	Ultra-thin (0.5-1mm) or flexible material	Standard thickness (2-3mm)
Torso Buoyancy	Optimized for swimming posture	Designed for upright posture
Legs	Cut to knee or calf for quick removal	Full length to ankles
Surface Treatment	Low-friction coating	Standard rubber surface
Price Range	NT$5,000-20,000	NT$2,000-15,000

The Importance of Fit

A wetsuit must fit like a second skin:

• Too loose: Water flows inside the suit, losing insulation and increasing drag
• Too tight: Restricts breathing, compresses the shoulders, and prevents a full stroke
• Ideal state: You can perform a full stroke while wearing it, with no obvious gaps or wrinkles

Fitting Checklist

1. No significant pressure at the neck, wrist, or ankle seals
2. When reaching both arms forward, the back should not feel overly tight
3. Perform a swimming stroke motion; the shoulders should not meet obvious resistance
4. When squatting down, the knee area should feel comfortable
5. After wearing it for 5 minutes, breathing should feel natural and unrestricted

Wetsuit Donning and Doffing Techniques

Donning Tips

1. Use plastic bags: Slip your feet into plastic bags before entering the legs to significantly reduce friction
2. Pull up in stages: Don’t pull it all the way up at once; adjust gradually from the ankles upward
3. Smooth out wrinkles: Ensure there’s no excess fabric bunched behind the knees or in the crotch
4. Apply lubricant: Use petroleum jelly or a dedicated anti-chafe balm on the neck and armpits
5. Zip up last: Confirm your body is fully positioned before zipping up the back

Quick-Doff Technique (T1 Transition)

1. Start unzipping while running in from the swim
2. Peel the upper body out of the suit, pulling it down to the waist
3. Once at your transition spot, step on the bottom of the suit
4. Pull each leg out one at a time
5. The entire process should be completed within 20-30 seconds

Important note: Quick removal in transition must be practiced at least 10-20 times beforehand. Race day is absolutely not the time for your first attempt.

Situations Where Skin Swimming Is Advantageous

In the following situations, not wearing a wetsuit may be the better choice:

Water Temperature Above 24°C

In warm water, wearing a wetsuit does more harm than good:

• Elevated core temperature can affect your entire race
• Fluid lost through sweat is hard to replenish in the later disciplines
• The speed gain is offset by the negative effects of overheating

Strong Swimmers

If your swimming technique is already excellent (100m pace under 1:15), the posture-correcting benefits of a wetsuit are minimal, while the negative impact of shoulder restriction may be more pronounced.

Ultra-Distance Events

In swims longer than 3.8 km, the cumulative strain a wetsuit places on the shoulders can lead to severe fatigue in the latter half.

Alternative Equipment Options

Speed Suit / Swim Skin

• Provides no buoyancy or insulation
• But reduces water resistance (compression material is slicker than skin)
• A good choice for races where wetsuits are prohibited
• No need to remove in transition

Sleeveless Wetsuit

• Retains torso buoyancy and insulation
• No shoulder restriction whatsoever
• Faster to remove
• Suitable for races with water temperatures between 20-23°C

Conclusion

A wetsuit is a powerful weapon for triathletes, but it is not a cure-all. The right choice depends on water temperature, your swimming ability, race rules, and personal preference. Practice swimming both with and without a wetsuit during training so you can handle any situation with confidence. Remember, the best gear is the one you know best and feel most comfortable in—so whatever your choice, make sure to practice thoroughly before race day.

Related Reading

• The Complete Guide to Wetsuits: Selection, Putting On/Taking Off, and Adjusting Your Swim Feel
• The Ultimate Triathlon Wetsuit Buying Guide: Key Factors from Material to Fit
• 2026 Triathlon Wetsuit Buying Guide: Matching Buoyancy, Flexibility, and Taiwan’s Water Temperature
• Wetsuit Buying Guide: Thickness, Buoyancy, and Range of Motion in Triathlon Wetsuits