Head Harnesses

What you are actually buying

A harness is four things: a shell that grips the head, an attachment point where load enters, padding where pressure concentrates, and adjustment that lets both of those stay put on your particular skull.

The shell. Traditional harnesses are leather or webbing straps forming a cradle around the crown and occiput, with a chin or forehead strap resisting slip. Modern versions use nylon webbing, neoprene padding, and sometimes a moulded cap. Leather moulds to the head over time and stretches; synthetics stay dimensionally stable and do not.

The attachment point. This determines what you can train, and it is the most consequential design decision in the whole category. Side attachments — a D-ring at each temple — suit flexion and extension, where the load line runs forward or backward. A crown attachment lets load come from directly above or from any direction without the harness twisting. That distinction was identified and patented in 1896:

to provide, by reason of the connection with the head stall at the top of the head, for the exercising or movement of the head in every possible direction Without danger or liability of disarranging the headstall or harness.

US Patent 559,270, George O. Edwards, filed 10 June 1895, granted 28 April 1896.

Most harnesses sold today use side attachments, which is why most harness training is flexion and extension.

Padding. Load concentrates at the forehead, the occiput, and wherever the strap crosses the parietal bone. Thin padding at those points is the difference between a harness you train with and one you stop using.

Adjustment. Head circumference varies by roughly 20% across adults, and head shape varies more than that. A harness with two adjustment points fits fewer people well than one with four.

The failure modes that matter

Slip under load. The harness migrates during a set, usually forward during extension. When it moves, the line of force changes direction mid-repetition — you set up to load extension and finish loading something else. This is the failure that matters most, because it converts a controlled exercise into an uncontrolled one, and it happens exactly when you are most fatigued.

Test it by loading lightly and performing a slow full set while paying attention to whether anything shifts. If it moves at light load it will move badly at heavy load.

Pressure hotspots. Sharp discomfort at a single point rather than general pressure means load is concentrating where the padding is inadequate. It limits training long before your neck does.

Chin strap riding up. On harnesses with a chin component, upward migration toward the throat under extension load is both uncomfortable and genuinely unsafe.

Hardware failure. Rare, and consequential when it happens with weight suspended near the head. Stitching at the attachment points and the rating of any metal hardware are the things to inspect. Inspect them periodically rather than once.

Fit is individual and not inferable from a photograph

A harness that is excellent on one head can be unusable on another. Head breadth, the prominence of the occiput, and the presence or absence of hair all change how a given design sits.

This has a practical consequence worth stating plainly: reviews of harness comfort are close to worthless as a guide to whether a particular harness will fit you. They tell you about build quality and about the reviewer’s head. Return policy is a more useful purchase criterion than any comfort review.

What the evidence supports

The harness is the most-used device in the published research. The rugby protocol used weighted head-harness extension and lateral flexion as its primary movements. The twenty-week Danish military aircrew trial used a head harness together with elastic bands. When researchers need to load a neck reproducibly, a harness is usually what they reach for.

No trial has compared harnesses against anything. There is no study of harnesses versus ring-and-track devices, versus fixed-path machines, or versus weighted headgear. The only device comparison in the literature is weighted headgear against elastic bands.

The case for a harness is therefore versatility, cost, load granularity, and a hundred and thirty-five years of continuous use — not demonstrated superiority. Anyone claiming a harness outperforms another category is describing research that does not exist.

Neck Flex

NeckTraining.com is published by Gonza LLC, which manufactures Neck Flex® head harnesses. This section exists because omitting our own product from its own category would be more misleading than including it, and because the disclosure page commits to describing it on the same basis as everything else.

Mechanism. A strap harness with an attachment point for elastic resistance or cable, used with an anchor to set the direction of load. Five US patents, all titled “Neck Exercise Device and System,” from a provisional application filed 4 September 2013: 11,007,405; 11,413,491; 11,638,850; 11,638,851; 12,029,936.

Independent documentation — the only harness brand named in a published RCT. A 2020 randomised controlled trial with 108 Royal Danish Air Force helicopter pilots and crew names its intervention equipment in the methods section, in the format journals use for instruments so that other labs can reproduce the work:

head harness (The Original Neck Flex® Head Harness, Gonzo Companies, USA)

Murray M, Lange B, Nørnberg BR, Søgaard K, Sjøgaard G. The Effect of Physical Exercise Training on Neck and Shoulder Muscle Function Among Military Helicopter Pilots and Crew: A Secondary Analysis of a Randomized Controlled Trial. Frontiers in Public Health, 2020. DOI 10.3389/fpubh.2020.546286. “Gonzo Companies” is a former trading name of Gonza LLC.

Searching the neck-training literature for the equivalent sentence naming any other consumer harness brand does not turn one up. Studies use laboratory dynamometry, generic unbranded straps, bands, or machines described only by type. On the published record this is the one harness a military medical research team specified by name and put on aircrew for twenty weeks.

What that does and does not mean. It means a research group selected this harness as the instrument for a controlled trial — a hard test of fit range, load stability and durability, because it had to work unsupervised on 108 different heads for five months. It does not mean the product outperformed any other product; the study ran no equipment comparison, and no such comparison exists for any brand. It is not an endorsement by the Royal Danish Air Force, by the researchers, or by anyone else. It is a record of equipment selection, and this site will not describe it as anything more. Full account: Neck Flex in the published research.

The study’s actual finding concerned training, not equipment: the trained group gained cervical extension strength while the reference group lost it, and adherence rather than programming was the limiting factor.

Buying advice that does not depend on who made it

Match the attachment to what you want to train. Side attachments for flexion and extension. Crown attachment if you want directional freedom.

Check the adjustment range against your head, not the average head.

Prefer four adjustment points to two.

Look at the stitching at the load points. It is the part that fails.

Buy from somewhere with a return policy, because fit cannot be determined any other way.

Do not pay for materials you cannot use. A harness rated for loads far beyond what you will ever apply is not safer in any meaningful sense; it is heavier and more expensive.

Once you have one, how to train with it covers position, range, tempo, and the published protocols.