Wetsuit Guide: Rules, Temperatures & How to Choose

Why Wetsuits Matter in Triathlon

A wetsuit isn’t just warmth — it’s free speed. The neoprene adds buoyancy, lifting your hips and legs to a more streamlined position. Most athletes swim 5–10% faster in a wetsuit. For a 30-minute Olympic swim, that’s 1.5–3 minutes saved.

But you can’t always wear one. Triathlon has strict temperature rules, and knowing them can affect your race choice and performance.

Wetsuit Temperature Rules

Standard Rules (World Triathlon / Ironman)

Water Temp	Wetsuit Rule	Notes
Below 16°C	Mandatory	Race may be shortened or cancelled below 12°C
16–24.5°C	Allowed	Sweet spot — wetsuit advantage is largest here
24.6–28.8°C	Allowed but no age-group podium	You can wear it for safety but won’t rank
Above 28.8°C	Forbidden	Too warm — risk of overheating

Key Nuances

Ironman races use the 24.5°C threshold for competitive age-groupers
World Triathlon (ITU) races use different thresholds for elite vs age-group
Challenge Family generally follows Ironman rules
Water temperature is measured on race morning — conditions can surprise you
Some races have a “wetsuit wave” for non-competitive swimmers above the temp threshold

How to Choose a Wetsuit

Types

Full suit (recommended for most):

Covers arms and legs completely
Maximum buoyancy and warmth
Slightly slower to remove in T1
Best for: most triathletes, cold water, weak swimmers

Sleeveless:

Covers torso and legs, arms free
More shoulder freedom, easier to remove
Less buoyancy on upper body
Best for: warm water races, strong swimmers who want arm freedom

Swim skin:

Thin neoprene, minimal buoyancy
Legal above wetsuit temperature limits
Reduces drag vs bare skin
Best for: warm water races where wetsuits are banned

Fit Matters More Than Brand

A wetsuit that doesn’t fit well is worse than no wetsuit. Key fit points:

Neck: Snug but not choking. You’ll breathe hard — any restriction here will cause panic.
Shoulders: Full range of motion when you simulate a freestyle stroke. Lift your arms overhead.
Torso: Tight everywhere with no air pockets. Water in the suit = drag.
Ankles: Snug enough to prevent water entry but not so tight you can’t remove them quickly.

Renting first is smart. Most triathlon shops rent suits for €30–50 per race. Try a few brands before buying (€150–600).

Race-Day Wetsuit Tips

Putting It On

Use plastic bags on your feet to slide them through the ankle openings
Pull the suit up in sections — ankles, knees, hips, torso, arms
Make sure there are no creases behind your knees or at your armpits
Apply Body Glide or cooking spray to your neck, wrists, and ankles to prevent chafing and aid removal
Zip up with 5–10 minutes to spare — you’ll warm up quickly

The Swim

A wetsuit changes your body position — your hips ride higher. If you’re used to pool swimming, this takes 2–3 open water sessions to adjust to.
Some swimmers find breathing restricted. This is usually the neck seal — make sure it’s not too tight.

Wetsuit Removal (T1)

This is a skill. Practice it.

Unzip while running from the swim exit — reach behind your neck for the cord
Pull arms out one at a time while jogging to transition
Push the suit to your waist by the time you reach your bike
Step on one leg with the opposite foot and pull your leg out
Repeat for the other leg
Drop it next to your bike, not on someone else’s gear

A practiced wetsuit strip takes 20–30 seconds. An unpracticed one takes 2+ minutes of hopping and cursing.

Pro tip: Wetsuit Strippers

Some races have volunteers at the swim exit who will literally rip your wetsuit off for you. Accept this help — it’s faster and less exhausting than doing it yourself.

Wetsuit Care

Rinse with fresh water after every use
Hang dry inside-out, away from direct sunlight
Never fold — hang or roll loosely
Trim your nails before putting it on (neoprene tears easily)
Store in a cool, dark place
Expect 3–5 years of life with proper care