August 25, 2026
JERSEY
Elite Athletics · Kit ArchiveNo. 12 · Kit Series
Inside Pro Elite · Kit Anatomy
Anatomy of the

HALF-ZIP
JERSEYS

Jacket-level warmth with a thermostat: the stretch knit athletes actually live in. What the half-zip jersey is, where it sits on the clo ladder, and how to choose one.

Team-issued · The mid layer · Not retail

A half-zip jersey is the mid layer of an issued athletics kit: a stretch polyester knit with a high collar and a sternum-length zip, worn for cold-weather training and around the stadium. On the ASHRAE garment scale it measures 0.34 clo — two hundredths below a thin jacket.

The zip is the point: a quarter open over a warm-up, closed to the chin in a cold call room. It is the only garment in the kit with a thermostat, and the most wearable piece a team ever issues.

This is Kit Anatomy, our series on each garment in the Pro Elite archive. Jump to the half-zips in stock, or read on for the clo ladder.

Half-Zip Jerseys · Key FactsVerified · updated August 2026
What it is
The mid layer: stretch knit, high collar, sternum-length zip — never raced
The warmth
0.34 clo — a thin jacket is 0.36; the half-zip is 0.02 behind
The unit
1 clo = 0.155 m²·K/W — comfort for a resting person at 21°C
The zip
Sternum-length: vents open, seals closed — the kit's only thermostat
Fabric
Polyester + elastane — 14 of 16 in this archive declare the blend
The reach
This rail spans 2014 to 2026 — jerseys outlive their kits
Race-issued vs retail
One cycle per kit, team quantities, no restock
In the archive
16 jerseys catalogued
Fig. 12 · The clo ladderASHRAE 55 · garment insulation
0.10.20.30.40.50.08T-SHIRT0.17SHORT-SLEEVEKNIT0.34HALF-ZIP/SWEATSHIRT0.36JACKET(THIN)0.44JACKET(THICK)0.02 clo apartThe half-zip does jacket-level work — and the zip is the thermostat a jacket does not have.1 clo = 0.155 m²·K/W — the insulation that keeps a resting person comfortable at 21°C
Insulation values for individual garments from ASHRAE Standard 55; 1 clo = 0.155 m²·K/W. Source: ASHRAE 55 garment table (Clothing insulation).
View the data
GarmentInsulation (clo)Kit role
T-shirt0.08Training and travel
Short-sleeve knit shirt0.17Polo / heavier tee
Long-sleeve sweatshirt (half-zip class)0.34The mid layer
Jacket, thin0.36Outer shell, mild weather
Jacket, thick0.44Outer shell, cold weather
01

What the half-zip is

The half-zip jersey is the middle of the issued wardrobe: warmer than a tee, lighter than a jacket, closer-cut than either. It is what athletes train in through the cold months and wear around the stadium when a jacket is too much — the layer between the layer and the skin.

Thermal engineering has a unit for what it does. Garment insulation is measured in clo — one clo keeps a resting person comfortable at 21°C — and on that scale the half-zip class sits at 0.34, two hundredths below a thin jacket's 0.36. The ladder above puts the whole issued wardrobe on one axis: the jersey does jacket-level work.

Nike Pro Elite Team 2014 Women Half Zip JerseyFrom this series · in the archiveNike Pro Elite Team 2014 Women Half Zip JerseyA 2014 team half-zip — the oldest cut in this rail, from the cycle that built the mould.90,00 €View piece →

What the jacket cannot do is the zip. A quarter of the way open over a warm-up, closed to the chin in a cold call room, half down on the bus — the half-zip is the only garment in the kit with a thermostat.

02

The mid layer, explained

Layering guides put every cold-weather outfit together the same way: a wicking base against the skin, an insulating mid layer over it, a shell on top when weather demands. The half-zip is the kit's answer to the middle slot — and in athletics it usually IS the outer layer, because sessions are short and shells only come out in rain.

The cut follows the job. A high collar that closes to the chin, a zip that stops at the sternum — low enough to vent, high enough that the garment pulls on over the head and stays anchored while running. Sleeves run long, often with thumb-loops in training cuts, and the body is trim so a shell fits over it without bunching.

Fourteen of the sixteen jerseys in this archive declare elastane alongside polyester — the half-zip is a stretch knit, not a woven. It moves like a base layer and insulates like a mid, which is the whole trick.

03

How a jersey is built

The construction brief is stable across suppliers and decades — a 2014 Nike team half-zip and a 2026 one differ in fabric finish, not in idea.

  • The knitPolyester with elastane — 14 of 16 pieces in this archive declare the blend. Stretch is structural: the jersey moves with the stride.
  • The zipSternum-length — the vent. Open for effort, closed for cold, and the collar stands either way.
  • The collarHigh and close, the wind seal for the neck a tee cannot offer.
  • The insulation0.34 clo on the ASHRAE garment scale — two hundredths below a thin jacket, with none of the bulk.
  • The cuffsLong sleeves, close cuffs, thumb-loops on training cuts — the wrist is where a mid layer leaks.
  • The badgeFederation or team mark on the chest, matching the race kit of its cycle — this is issued kit, not fan wear.
Nike DSM-Firmenich Team Pro Elite 2026 Training Half Zip JerseyFrom this series · in the archiveNike DSM-Firmenich Team Pro Elite 2026 Training Half Zip JerseyThe newest cycle in the rail — a 2026 pro-team training half-zip, same idea, current knit.180,00 €View piece →

The long-sleeve training shirt is the half-zip's little sibling — same knit, no collar, no zip — and teams issue both because the two-hundredths of clo between them is sometimes exactly the difference a session needs.

04

How to choose yours

Choosing a half-zip is choosing the workhorse — the piece that gets worn, not displayed.

  • Trim, not tightThe jersey should sit close enough to go under a shell — if it fits like a hoodie, it is a size up from its job.
  • Check the zip garageA good half-zip parks the zip pull in a fabric garage at the chin — the detail that separates issued kit from cheap copies.
  • Match the cycleThe jersey carries its kit's year and colours — pair it with the race pieces of the same season.
  • Old rails run deepLike jackets, jerseys survive their kits — this rail reaches back to 2014, further than most singlet rails can.
  • Stretch is the tellA team half-zip has elastane in the tag; an all-poly one is usually a supporter piece, not an issue.
  • Wear itThe half-zip is the most wearable garment in any issued set — street-ready in a way briefs and singlets never were.
Nike DSM-Firmenich Team Pro Elite 2026 Training Long Sleeves ShirtFrom this series · in the archiveNike DSM-Firmenich Team Pro Elite 2026 Training Long Sleeves ShirtThe little sibling — a long-sleeve training shirt, same knit without the collar and zip.180,00 €View piece →

If the singlet is the trophy and the jacket is the witness, the half-zip is the tool: the garment a professional actually wore most hours of their season.

Two all-Navy cross country athletes walking a race course in team half-zip mid layers
The mid layer at work — all-Navy cross country athletes walk the Armed Forces championship course in team half-zips, Maryland, February 2009. Photo: MC2 Jhi L. Scott, U.S. Navy, public domain / Wikimedia Commons.
Race-Issued · Archive Originals

Half-Zip Jerseys in the Archive

Federation and pro-team half-zips from 2014 to the current cycle — the mid layer of the issued kit, made for a single season and matched to the race pieces in this archive. In-stock first; sold-out pieces stay listed because the runs rarely return.

Frequently Asked Questions

What is a half-zip jersey in athletics?

The mid layer of an issued team kit: a stretch polyester knit with a high collar and a sternum-length zip, worn for cold-weather training and around the stadium. Warmer than a tee, lighter and closer-cut than a jacket, with the team badge of its kit cycle.

How warm is a half-zip compared to a jacket?

Nearly identical. On the ASHRAE 55 garment scale the long-sleeve sweatshirt class measures 0.34 clo against 0.36 for a thin jacket — two hundredths apart. The difference is the zip: the half-zip vents, a jacket only opens.

Why do half-zips stop the zip at the chest?

So the garment pulls on over the head and stays anchored while running, with enough opening to vent heat and a collar that still closes to the chin. Full zips flap; half-zips hold.

What are team half-zips made of?

Polyester knits with elastane — 14 of the 16 jerseys in this archive declare the blend. The stretch is structural: the jersey has to move with the stride rather than sit over it.

How should a half-zip jersey fit?

Trim: close enough to layer under a shell, loose enough for a tee beneath. If it fits like a hoodie it is oversized for its job. Issued cuts run true to street sizing.

Sources and References

Tags: