Rashguard — kompletny przewodnik. Tkaniny, szwy, sublimacja i jak zamówić własny model

Rashguard anatomy — what it is made of

A rashguard is a compression top worn in combat sports — primarily Brazilian jiu-jitsu (BJJ), MMA, and submission wrestling. Its role is functional: protecting the skin from mat abrasions (hence the name — "rash" as in skin irritation), reducing friction during gripping exchanges, and providing muscle compression during exertion.

Unlike an ordinary sports top, a rashguard is engineered for very specific stresses: constant four-way stretch, contact with the mat, contact with a training partner's skin and gi, washing after every session, and forceful pulling on the sleeves during submission attempts.

Fabrics — polyester interlock vs nylon/spandex

Fabric choice is the single most important decision when designing a rashguard. Two fabrics dominate the market:

Polyester interlock — 88% PES / 12% elastane, 180–200 g/m²

This is the market standard — used in the vast majority of BJJ rashguards. Polyester delivers excellent colour retention (sublimation dyes bond deep into the fibre), fast drying, and strong resistance to shape distortion after repeated washing. The elastane (Lycra) component provides four-way stretch, essential for freedom of movement in grappling.

A fabric weight of 180–200 g/m² is the sweet spot: light and breathable, yet stable enough not to become see-through when stretched or to lose its shape. Below 160 g/m² the fabric is too thin and will show through under tension.

Nylon/spandex — 80% PA / 20% elastane

The premium segment. Nylon is softer to the touch than polyester, with a silky hand feel and greater abrasion resistance — important in no-gi, where the mat makes direct contact with bare skin. The drawbacks are a higher cost and limited compatibility with sublimation printing: nylon requires specialist sublimation inks and precise transfer temperatures, which increases the margin for error and the cost of production.

Flatlock seams — why they matter

Flatlock is a sewing technique in which two layers of fabric are joined by overlapping their edges and stitching them together with a specialist multi-needle machine. The result is a flat, flexible seam that creates no raised ridge on the inside of the garment.

A conventional overlock seam (the type used in t-shirts) produces a thicker ridge on the inside — detectable under a fingertip, and irritating under prolonged skin contact. In grappling, where your training partner grabs your shoulder, back, underarm, and torso for a five-minute round, even a small raised seam becomes a friction point. After an hour of training, that means skin abrasions.

A rashguard sewn with flatlock seams throughout — at the shoulders, underarms, sides, cuffs, and collar — eliminates this problem entirely. Flatlock is also more elastic than overlock, so it does not restrict movement in extreme positions.

Sublimation printing as the standard for rashguards

Sublimation printing is the only decoration method that makes sense for rashguards — for several reasons simultaneously.

No ink layer on the surface. DTF, screen printing, and heat transfer all deposit a layer of ink or film on top of the fabric. In a rashguard, where an athlete is in direct contact with bare skin and a partner's gi for 60 minutes, any surface print layer becomes a potential friction point. After several dozen training sessions, DTF prints and transfers begin to crack and peel at seams and edges. Sublimation dye is chemically bonded into the fibre — it cannot separate from the fabric.

Unlimited graphic freedom with no colour surcharges. Club rashguards often feature complex artwork — logos, geometric patterns, athlete-specific graphics. Sublimation allows the entire rashguard to be covered in any graphic without colour restrictions and without additional charges.

Per-unit personalisation. For competition athletes you need rashguards with individual numbers or names. With sublimation, every unit can carry a different print at no extra cost — something that is simply not achievable with screen printing.

The one limitation: sublimation works only on light-coloured polyester fabrics. If your club wants rashguards on black or dark navy fabric with a coloured logo, DTF with a white underbase or embroidery will be required instead.

Short sleeve vs long sleeve vs grappling leggings

For club orders, we recommend starting with a full set: long-sleeve rashguard + grappling leggings. This combination covers all competition scenarios and presents a unified look at events regardless of federation rules.

How to order rashguards for your club — step by step

Sizing for a BJJ/MMA club

Rashguards ordered for an entire club need to cover a wide range of body types — from lighter athletes at 60 kg through to heavyweights at 100 kg and above. A typical size distribution for a club of 30 people:

• XS: 1–2 units (women, juniors)
• S: 4–5 units
• M: 8–10 units (most common size)
• L: 7–8 units
• XL: 4–5 units
• XXL: 2–3 units
• 3XL: 1 unit (optional)

We recommend ordering 2–3 spare units in the most popular sizes (M, L) — to cover new members or replace damaged pieces. With the minimum order quantity of 50 units, you have full flexibility in how you distribute across sizes.

The most common mistakes when ordering rashguards

Cotton instead of polyester. Already covered above — a cotton rashguard is not a rashguard. Check the fabric composition before signing the order.

Overlock instead of flatlock. A cheaper seam that will become a problem within a few weeks of training. Flatlock costs more, but the difference is roughly 5–10 PLN per unit — a marginal cost that translates directly into wearability.

Logo placement in contact zones. Embroidery or DTF on the shoulder or rear upper arm — areas that are directly grabbed and abraded in no-gi — will deteriorate quickly. Sublimation does not have this problem. If you do use embroidery (e.g. on the chest), ensure it sits low enough that it will not rub against a partner's neck during a clinch.

Insufficient compression. A rashguard that is too loose loses its compressive function and traps air between the body and the fabric — creating a "ballooning" effect during takedowns. The cut should be fitted: in close contact with the body, but not restricting movement.

No personalisation on the club order. If you plan to send athletes to competitions, include individual numbers or names from the outset — at the first order. Adding personalisation retrospectively is more expensive and slower than incorporating it into the original production run.