A swimmer emailed us last week asking how a specific wetsuit from another brand compares to ours, spec for spec. We're skipping that request. Not because the comparison makes us nervous, but because it answers the wrong question. The real question isn't which suit wins on a hangtag. It's whether a given suit will work for your body, your race distance, and how many hours you spend in open water each month.
That question has answers rooted in neoprene chemistry, buoyancy placement, and fit mechanics. Below is the framework we'd want any swimmer carrying into a wetsuit purchase, whether they end up in a Blue70 suit or something else entirely.
Buoyancy isn't a single number
Every wetsuit ad promises better buoyancy. Fine. But buoyancy without a location attached to it doesn't tell you much. Leg tissue in most swimmers carries more dense muscle and less air-trapping structure than the torso. Left alone, legs sink. Correcting that drop, not maximizing flotation in general, is the actual job of a wetsuit.
A suit can pile thick neoprene across the chest and still leave the hips and thighs thin. You'll feel floatier standing in the shallows. You won't feel any different once your legs start trailing underwater at stroke 400.
This is why Blue70's LIFT panel system places buoyant neoprene at the hips and thighs and keeps the shoulders and lats thin and flexible. The point isn't a bigger number on a spec sheet. It's fixing the actual imbalance between a chest that already floats and legs that don't.
So when you try on any wetsuit, check where the thick panels sit. A 5mm slab in the wrong spot does less for your body position than 3mm in the right one.
Flexibility has a cost
Neoprene comes in cell grades, and cell count matters more than most product copy lets on. Blue70 builds its suits from Yamamoto 38, 39, and 40-cell neoprene. Higher numbers mean more nitrogen gas cells packed into the rubber, and more nitrogen cells mean more flex per millimeter of material.
Two suits can list an identical 1.5mm shoulder panel and swim nothing alike, because cell grade decides how much resistance your shoulder feels on every single recovery. Lower-grade neoprene at the same thickness tires your shoulders out faster over a 1.2-mile swim leg. It doesn't compress and spring back as efficiently through a full stroke cycle.
A sprint triathlete racing 750 meters rarely notices any of this. Someone swimming 60-plus minutes in a suit notices it in the last third, right when shoulder fatigue starts wrecking rotation and catch.
Here's the catch. More flexible neoprene wears out faster. Blue70 says this openly about its own flagship, the Helix: thin, highly flexible panels built for total race-day performance will break down quicker under frequent training use than a suit like the Reaction, built with tougher neoprene for swimmers logging multiple open-water sessions a week. It's a design choice stated plainly on the brand's own product pages, not a flaw buried in fine print, and it should shape what you buy based on how often you actually swim in it.
Train in open water once or twice a month? Shoulder freedom on race morning outweighs long-term durability. Swim three times a week from May through September? Take the tougher neoprene. Nobody wants a suit delaminating in August.
Why a wetsuit should feel tight on land
The most common wetsuit complaint has nothing to do with buoyancy or flex. It's fit, specifically water flushing in and out at the neck, wrists, or ankles.
A wetsuit doesn't keep you dry. It lets in a thin layer of water, your body warms that layer, and the warmed water works as insulation as long as it stays put. Every gap where fresh water flushes through defeats the whole mechanism. You end up reheating new cold water constantly instead of holding onto the layer you already warmed.
That's why a wetsuit needs to feel snug on dry land, snug enough to be a little uncomfortable standing still. Swimmers who size up for comfort in the shop are usually the ones reporting cold flushing through once they hit the lake. A loose suit is working exactly as a loose suit works: it lets water pass.
Try this instead of the mirror test. Put the suit on, then raise both arms overhead and rotate through a full freestyle recovery motion. If it fights you at the shoulder standing still, it will fight you at stroke 800 too. If it's tight at rest but moves freely through that rotation, that's the fit you want. Comfort belongs in the water, not on the beach.
This is also the logic behind Blue70's Test Swim policy. A wetsuit's real fit only shows itself once you're moving through open water under actual thermal and mechanical load. Land fit and swim fit are related. They aren't identical.
Women's fit is a pattern problem, not a sizing problem
Plenty of women swimmers have tried working around poor fit by buying a smaller men's suit and hoping the proportions land close enough. They usually don't, because the mismatch isn't about overall size. It's about where the material sits relative to bust, torso length, and hip width.
Femme Fit sizing tackles this at the pattern level, not just the size chart. It includes a refined cut through the bust and torso, a lowered neckline shaped around the real difference in women's neck and shoulder geometry to cut down on chafing, and a longer zipper opening for faster, easier entry.
That zipper detail matters more on race morning than it sounds. A short zipper opening forces the suit higher over the hips during donning, which costs seconds in transition and puts strain on the zipper track. A longer opening solves both problems at once.
If a suit has disappointed you despite matching your measurements on the size chart, the pattern is likely the real issue. A suit built from the ground up on a women's pattern swims differently than a men's cut scaled down to a smaller size, even at an identical listed size.
Water temperature sets the category before anything else matters
None of the above helps if you're in the wrong category of suit for the water. Below roughly 56 to 58°F, a purpose-built thermal suit adds real warmth that a standard full suit can't match, mostly through fuller interior lining rather than thicker neoprene alone. Above roughly 70 to 72°F, a full suit over a long swim traps more heat than most swimmers want, which is where sleeveless designs and swimskins earn their place.
Wetsuit-legal temperature cutoffs vary by sanctioning body and shift from season to season. Check your race's current rules directly instead of trusting a number passed around at the pool deck.
Four questions worth asking before you buy
Skip the spec sheet next time and run any wetsuit through these instead:
- Where does the buoyant material sit, and does it match where your body actually needs lift?
- What neoprene grade is used, and does that flexibility match your race distance and how often you train?
- Does it fit snugly enough on land to stop flushing while still letting your shoulders rotate freely?
- If you're a woman, was the pattern built around your body, or borrowed from a men's block?
Those four questions tell you more than any buoyancy claim printed on a tag. A wetsuit's job is to fix your body position and cut drag. Nothing more complicated than that. Understanding the mechanics behind it is what lets you choose well instead of guessing.
Want to put a suit through this test yourself before committing? Blue70's Test Swim policy lets you swim in a wetsuit in open water and still return or exchange it, as long as it comes back clean, dry, and with tags attached.
Happy swimming.
