Thermal Wear for Freediving and Spearfishing

Freediving and spearfishing put different demands on gear than scuba does, and most standard wetsuits were never designed with those demands in mind. You are holding your breath, moving your diaphragm as much as possible, duck-diving repeatedly, and often drifting in the water for long stretches waiting for fish or waiting to descend again. Thermal wear built for warmth without bulk suits that kind of diving very well, and it is worth understanding why before you kit up for your next session.

Why a standard wetsuit can fight you underwater

A thick wetsuit is built to trap and warm water, and it does that job. But thickness and stiffness are exactly what a freediver or spearfisher does not want. A tight, thick suit restricts the chest and diaphragm right when you need to breathe up fully before a dive and equalise cleanly on the way down. It also adds drag on every duck dive and every kick, which costs you energy you would rather spend on bottom time. Open-cell wetsuits solve some of this for dedicated freedivers, but they are delicate, expensive, and still bulky out of the water.

What freedivers and spearfishers actually need

Strip it back to the basics and the list is short:

• Warmth for time spent still in the water. Drifting, waiting, watching - this is where breath-hold divers lose heat, often more than the active swimming does.
• Freedom of movement. Full range through the chest, shoulders and hips for equalising, finning and duck-diving.
• Low drag. Anything that fights the water on the way down costs energy and bottom time.
• Comfort on the surface between dives. Sitting on a boat or drifting on the surface with a snorkel in, waiting for the next descent, is where wind-chill catches people out.
• Fast drying. Long sessions often mean multiple swims across a day, sometimes over several days on a trip.

Where Sharkskin fits into that picture

Sharkskin's thermal ranges - Chillproof and T2 Titanium - are thin, flexible layers rather than thick neoprene, so they do not fight your breathing or your movement the way a heavier wetsuit can. Worn on its own in warmer water, it gives useful warmth without adding the bulk that slows you down on a duck dive. In cooler conditions, it works as a layer under a lower-thickness wetsuit, so you get extra warmth for longer sessions without going up to a suit that restricts you.

It also does something a wetsuit does not: it blocks wind-chill on the surface. For spearfishing especially, where you might be floating and scanning for long stretches between drops, staying warm on the surface matters just as much as staying warm at depth.

A note on gear that doesn't fight you

Ask most experienced freedivers and spearfishers what they actually want from their gear and it usually comes down to this: something that disappears once you are in the water, so you can focus on your breath-hold and the dive itself rather than fighting your own kit. Thin, flexible thermal wear is built around that idea, where a stiff, thick wetsuit is built around a different one - maximum insulation, with mobility as an afterthought.

If you want to understand where thermal wear and a standard wetsuit each make sense, our Sharkskin vs neoprene wetsuit comparison covers the trade-offs in detail. And if you are trying to decide between Sharkskin's two ranges for your conditions, see our guide to Chillproof vs T2 Titanium.

So what should you wear?

If your sessions involve a lot of duck-diving, drifting, and time spent still in the water, a thin flexible thermal layer is very likely going to serve you better than a thick wetsuit, on its own in warmer water or layered underneath one when it is cooler. Less bulk, more mobility, and you stay warmer on the surface too.

It is also worth thinking about the whole day, not just the time underwater. Spearfishing trips in particular tend to mean long stretches on a boat or shoreline between drops, getting in and out repeatedly as you follow fish or change spots. Gear that dries fast and does not hold onto the cold once you are out of the water makes those in-between stretches far more comfortable, and that adds up over a full day on the water.

Our full Sharkskin range is here if you want to see what fits your conditions - get in touch if you want a hand picking the right layer for freediving or spearfishing.