Which Helmet Tech Actually Reduces Concussions?

Understanding Rotational Impact Protection

Every year, roughly 80,000 cyclists in the United States visit emergency rooms with head injuries. Standard helmet foam absorbs direct impacts effectively, but the brain is particularly vulnerable to rotational forces that twist the head during angled crashes. Three competing technologies now claim to address this problem: MIPS, WaveCel, and SPIN. Understanding how each works helps you make an informed choice about which protection actually matters.

The Science of Rotational Brain Injury

Your brain floats in cerebrospinal fluid inside your skull. In a direct impact, the skull stops suddenly, but the brain continues moving briefly before rebounding off the inner skull wall. This causes the classic concussion mechanism.

Rotational injuries add another dimension. When your head hits the ground at an angle, it doesn’t just stop—it rotates. This rotation creates shearing forces within the brain as different layers of tissue move at different speeds. Studies suggest these rotational forces cause more diffuse brain injuries and contribute significantly to concussion severity.

Traditional helmet EPS foam compresses to absorb linear impact energy, but it does nothing to reduce rotation. The three technologies below attempt to address this gap.

MIPS: Multi-Directional Impact Protection System

MIPS is the oldest and most widely adopted rotational protection technology. Developed by Swedish neurosurgeon Hans von Holst and researcher Peter Halldin at the Royal Institute of Technology in Stockholm, MIPS uses a low-friction layer between the helmet’s outer shell and inner liner.

How it works: A thin plastic slip plane sits inside the helmet, attached by elastomeric connectors that allow 10-15mm of movement in any direction. During an angled impact, the outer helmet rotates while the slip plane—and your head—rotate slightly less. This relative movement redirects rotational energy away from your brain.

The evidence: MIPS has published more third-party testing data than competitors. Virginia Tech’s helmet rating system, which specifically tests for rotational acceleration, consistently ranks MIPS-equipped helmets among the safest. In controlled lab tests, MIPS reduces rotational forces by 10-40% depending on impact angle and severity.

Limitations: The slip plane adds weight (roughly 20-30 grams) and can feel slightly warmer since it reduces ventilation contact with your head. Some riders report the MIPS liner feeling loose or moving during normal riding, though this doesn’t affect crash protection.

Availability: MIPS licenses its technology to over 100 helmet brands. You’ll find it in helmets ranging from $60 entry-level models to $300+ premium options from Giro, Bell, Smith, POC, Lazer, and dozens of others.

WaveCel: Bontrager’s Collapsible Cellular Structure

Trek’s Bontrager brand introduced WaveCel in 2019 as a revolutionary alternative to MIPS. Rather than adding a slip plane, WaveCel replaces the traditional EPS liner with a cellular structure that both flexes and glides.

How it works: WaveCel is a collapsible cellular material that forms the entire impact-absorbing liner. On impact, the cells flex (reducing linear force), then glide relative to each other (reducing rotational force), then crush if the impact is severe enough. The material handles both linear and rotational protection in one integrated system.

The evidence: Bontrager’s initial marketing claimed WaveCel was “up to 48x more effective” than standard helmets at preventing concussions. This claim generated significant controversy and has been walked back. Independent testing shows WaveCel performs comparably to MIPS in most scenarios, slightly better in some impact angles, slightly worse in others. Virginia Tech rates several WaveCel helmets with 5 stars, their highest safety rating.

Limitations: WaveCel is proprietary to Trek/Bontrager, limiting consumer choice. WaveCel helmets tend to cost more than comparable MIPS options. The cellular structure may feel different against your head than traditional foam, and some riders find the fit less comfortable.

Availability: Only available in Bontrager helmets, including the Specter, Blaze, Rally, and Ballista models. Prices range from $150 to $300.

SPIN: Shearing Pads Inside

POC, the Swedish helmet company known for distinctive design, developed SPIN (Shearing Pads Inside) as their approach to rotational protection. SPIN shares conceptual similarity with MIPS but implements it differently.

How it works: Instead of a continuous slip plane, SPIN uses multiple silicone pads positioned at key contact points inside the helmet. These pads are attached to the EPS liner but allow 10-15mm of shear movement in any direction. During impact, the pads absorb rotational energy by shearing rather than sliding.

The evidence: POC has published less independent testing data than MIPS, making direct comparison difficult. Virginia Tech’s database includes several POC helmets with SPIN, and they generally rate well but not consistently better than MIPS alternatives. The technology is relatively newer and less studied than MIPS.

Limitations: SPIN is proprietary to POC helmets only. The pad placement creates a specific fit that may not suit all head shapes. POC helmets tend toward the premium end of the market, with most SPIN-equipped models costing $180-$350.

Availability: POC Ventral, Omne, and Kortal models all feature SPIN. POC positions these as premium offerings with distinctive Scandinavian design aesthetics.

Do These Technologies Actually Work?

This is the question every cyclist wants answered, and the honest response is: probably, but we can’t be certain of the real-world magnitude.

Lab testing consistently shows all three technologies reduce rotational acceleration in controlled impacts. The Virginia Tech helmet rating system, which uses an impact protocol specifically designed to evaluate rotational protection, gives top ratings to multiple helmets using each technology.

However, translating lab results to real-world concussion prevention is challenging. Cyclists crash in infinite variations of speed, angle, surface, and body position. No lab can replicate this complexity perfectly. We also lack large-scale epidemiological studies comparing concussion rates between riders using different helmet technologies.

What we can say with confidence: a helmet with rotational protection technology is not worse than one without, and the physics suggest it should be better. Whether that difference prevents concussions in practice remains an active research question.

Which Technology Should You Choose?

For most cyclists, the practical differences between MIPS, WaveCel, and SPIN are less important than:

Fit: A helmet that fits your head properly protects better than one that doesn’t, regardless of technology. Try before buying whenever possible.

Ventilation: You’re more likely to actually wear a comfortable, well-ventilated helmet. All the protection in the world doesn’t help if you leave the helmet at home.

Price: MIPS appears in helmets at all price points. WaveCel and SPIN cluster at premium prices. Don’t overpay for brand names if budget matters.

Availability: MIPS works with any helmet brand you prefer. WaveCel limits you to Bontrager. SPIN limits you to POC.

Recommendations by Budget

Under $100: Bell Avenue MIPS ($65), Giro Register MIPS ($70), Specialized Align II MIPS ($55). At this price point, MIPS is your only rotational protection option, and these helmets provide excellent value.

$100-$200: Giro Syntax MIPS ($150), Bontrager Specter WaveCel ($150), Lazer Z1 KinetiCore ($200). This range offers the most competition between technologies. Try different options and choose based on fit and comfort.

$200+: POC Ventral SPIN ($275), Bontrager Ballista WaveCel ($300), Specialized S-Works Prevail II MIPS ($275). Premium helmets at this level all perform well in testing. Choose based on weight, ventilation, aesthetics, and fit rather than rotational technology claims.

The Bottom Line

Any of these three technologies provides better rotational protection than no technology at all. If you’re replacing an older helmet without rotational protection, upgrading to MIPS, WaveCel, or SPIN makes sense.

Don’t get paralyzed by marketing claims about which technology is “best.” The differences between them are measurable in labs but uncertain in real-world crashes. Focus on finding a helmet that fits well, ventilates adequately for your riding conditions, and comes from a reputable brand with consistent quality control.

And remember: the most important factor in helmet safety is wearing one every ride. The safest helmet technology is worthless hanging in your garage.