Neck Strength and Concussion Risk

The headline finding

The largest study to examine this measured 6,704 high school athletes across 51 high schools in 25 states, in boys’ and girls’ soccer, basketball and lacrosse, with certified athletic trainers recording pre-season neck strength and then tracking concussion incidence across the season.

Smaller mean neck circumference, smaller mean neck to head circumference ratio, and weaker mean overall neck strength were significantly associated with concussion… After adjusting for gender and sport, overall neck strength remained a significant predictor of concussion (p = 0.004). For every one pound increase in neck strength, odds of concussion decreased by 5 % (OR = 0.95, 95 % CI 0.92-0.98).

Collins CL, Fletcher EN, Fields SK, Kluchurosky L, Rohrkemper MK, Comstock RD, Cantu RC. Neck strength: a protective factor reducing risk for concussion in high school sports. Journal of Primary Prevention, 2014 Oct;35(5):309–19. DOI 10.1007/s10935-014-0355-2. PMID 24930131.

Five percent per pound compounds. An athlete who adds ten pounds of neck strength across an off-season is, on these figures, associated with roughly 40% lower odds of concussion. Twenty pounds — well within what a season of consistent training produces — is associated with lower odds still.

The authors’ own conclusion was that neck strength could be used to identify athletes at higher risk, who “could be targeted for concussion prevention programs.” The paper’s title calls neck strength “a protective factor reducing risk.”

Why this matters more than most risk factors

Most of what predicts concussion risk cannot be changed. Sex, sport, position, age, prior concussion history, and the behaviour of the person hitting you are all outside an athlete’s control.

Neck strength is different. It is one of the very few modifiable ones. It responds reliably to training, it can be measured, and it can be improved in weeks.

That fact alone justifies training it, independent of how the remaining evidence resolves.

The mechanism

A concussion results from acceleration of the brain within the skull, both linear and rotational. For a given impulse delivered to the head, the resulting acceleration depends on the effective mass being accelerated.

A head coupled to a braced torso by a strong, stiff neck presents a larger effective mass than a head sitting on a weak, compliant one. Larger effective mass, same impulse, lower acceleration.

The stiffening is produced by co-contraction of the cervical musculature, which is why both strength and the ability to brace matter. It also explains why anticipated impacts differ from unanticipated ones.

What is established, and what is not

Established, high quality: resistance training reliably and substantially increases neck strength. A 2024 systematic review of 26 studies found a pooled effect of SMD 0.85 (95% CI 0.57 to 1.13), rated high quality — the top rating available.

Established, observational: athletes with stronger necks experience fewer concussions (Collins 2014, n=6,704). A more recent study reported the same relationship in high school rugby union and rugby league players.

Reviewed and recommended: a 2019 Rutgers review in the Journal of Orthopaedic and Sports Physical Therapy surveyed the cervical-spine literature and identified neck strength, neck size, and neutral neck posture as protective characteristics, recommending that clinicians assess the cervical spine at pre-participation physicals and include neck-strengthening work in pre-season training. The authors also noted that female athletes typically have less neck strength and experience higher concussion rates, more severe symptoms and longer recovery — which makes the case for training girls’ necks stronger, not weaker.

Brown A, Esopenko C, et al. Cervical Spine Characteristics and Concussion Risk. Journal of Orthopaedic and Sports Physical Therapy, 2019. Rutgers School of Health Professions.

Not yet run: a trial that trains one group’s necks, leaves another untrained, and counts concussions in each. The 2024 systematic review found no study has done this, and also found no significant effect of resistance training on measured head acceleration.

Ivanic B, Cronström A, et al. Efficacy of exercise interventions on prevention of sport-related concussion and related outcomes: a systematic review and meta-analysis. British Journal of Sports Medicine, 2024;58(23):e108260. DOI 10.1136/bjsports-2024-108260. PMID 39242177.

Mixed, in soccer heading specifically: a 2025 systematic review in Sports Medicine found that head and neck size and neck strength predict both linear and rotational acceleration during a purposeful header, and that female players sustain greater head accelerations than males — but also concluded that traditional neck strengthening was not effective at reducing head acceleration, while programmes adding neuromuscular work appeared to be. A small 2022 randomised trial in collegiate soccer players found no change in heading kinematics after six weeks.

Blyth R, Farrell G, Zoellner A, Ahmed OH, Bussey M, Galea O, Sole G. What Factors Influence Head Acceleration During a Purposeful Header in Soccer Players? A Systematic Review. Sports Medicine, 2025;55(7):1677–1741. DOI 10.1007/s40279-025-02209-2.

A plausible reading, offered as hypothesis rather than finding: a deliberate header is an anticipated impact, and an anticipated impact is already met with co-contraction. Adding strength to an already-braced neck may not move that number much, while the impacts that actually produce concussions are disproportionately the unanticipated ones. Full discussion: neck training for soccer and lacrosse.

What the gap means in practice. Two things are solidly established — training makes necks stronger, and stronger necks are associated with fewer concussions — and the study formally joining them has not been conducted. That is a gap in the literature, not evidence against the proposition.

It is also, realistically, a study that may never be run at the scale required. Randomising thousands of adolescent athletes into a deliberately untrained control group, for a season, to count concussions, is an expensive and ethically awkward proposition. Waiting for it before acting is a decision with its own consequences.

How this site states it

Supported: neck strength is associated with reduced concussion risk, at approximately 5% lower odds per pound in the largest study to measure it.

Supported: training reliably increases neck strength, on high-quality evidence.

Supported: neck strength is one of the few modifiable concussion risk factors available to an athlete.

Not claimed: that neck training prevents concussion, or eliminates risk, or that any specific percentage reduction in concussions follows from a training programme. Collins measured strength and outcomes; it did not test an intervention.

The distinction is not hedging. It is the difference between a claim that survives scrutiny and one that does not — and this site is published by a company that sells neck-training equipment, which makes getting it right a matter of credibility rather than caution.

What to actually do about it

If neck strength is protective, and training builds neck strength, the practical question is how to build it efficiently and safely.

The answer that emerges from every controlled protocol in the literature is progressive resistance with equipment that delivers consistent, measurable, progressable load. Every published trial that produced measurable strength gains used a harness, a weighted helmet, bands, or a machine. None used unstructured self-applied pressure, because inconsistent load cannot be progressed and cannot be measured.

The programming guide has the complete published protocols. The device taxonomy covers what each category of equipment does. For most athletes, a head harness is the practical answer — it loads every direction, accepts load in small increments indefinitely, and is what the research uses.

For parents and coaches

Neck strength is measurable, trainable, and associated with lower concussion odds in the largest study of high school athletes yet conducted. Building it is inexpensive and takes minutes a week.

It is not a helmet, it is not a substitute for coaching good technique, and it does not make an athlete safe. What it does is improve one of the very few risk factors that an athlete has any control over at all.

If someone tells you a product prevents concussions, they are going beyond what anyone has shown. If someone tells you neck strength does not matter, they have not read Collins 2014.