There are two analogies used by the team at MIPS to help explain what’s at stake, and why preventing rotational forces from transferring to the brain is important.

“The human brain is very similar to water when it comes to shear properties,” says Halldin.

Like water, the brain cannot be compressed. If you expose a bowl of water or a human head to a linear force, Halldin says you will see very low deformation figures for the central part of the bowl of water and the brain. However, if you introduce a rotational force you will see higher strain values on the centre.

Marcus Seyffarth, head of product development at MIPS, uses the analogy of stretching a rubber band to explain the effect these strain values can have.

The more you stretch an elastic band the less likely it is to return to its original shape, and the same can be said for rotational forces in the brain.

“If you get a little bit of rotational motion in the brain, nothing will happen. If you get a little bit more, you might be a little bit concussed, but you’ll be ok. But if you get a little more than that you might get a severe traumatic brain injury.”

This severe traumatic brain injury can manifest in different ways. The axons, or the nerve fibres, in your brain can shear causing diffuse axonal injury (DAI), or the veins can tear leading to a subdural haematoma, where blood collects between your brain and skull. This can lead to various symptoms from feeling sick to paralysis on one side of the body.

Who created MIPS?

MIPS’ origins extend back to 1995 when Halldin, a PhD student at the time, was researching the biomechanics of head and neck injuries.

“I understood that the brain could slide inside of the skull in the cerebrospinal fluid. So I asked my supervisor Hans von Holst, the brain surgeon, if this safety system could be applied in a helmet and he said ‘that’s a great idea’. So we started to work on this idea and found that it probably had a good potential to increase safety in helmets.”

The pair started to research the types of impacts experienced by bicycle and motorcycle helmets as well as the current test standards.

Through this, they realised the standards tested only for linear impacts rather than rotational forces, and came up with the idea for MIPS in 1996. The first scientific publication regarding MIPS was published at the beginning of the 2000s.

Halldin and von Holst then founded MIPS AB in 2001, and in 2007 launched the first MIPS helmet, which was actually an equestrian helmet.

The company released the first third-party helmet with MIPS a few years later. They realised there was greater potential to get MIPS into helmets if they worked with other helmet manufacturers, as opposed to producing their own. This is a business model much like Gore-Tex or Polartec, which sell their fabrics to different clothing companies.

“We were a small company,” says Halldin. “It takes quite a lot of effort to get your product in different helmet segments.

“At that time in 2010, we felt we had a better possibility to save more lives if we became an ‘ingredient’ brand. As a result, we’ve been able to integrate into many, many more helmets than we would’ve done if we were just a helmet brand ourselves.”

Now, MIPS works with helmet manufacturers to include MIPS technology in their helmets from the very beginning of the design process, and the company also works with brands to advise on other aspects of helmet design.

Does MIPS really work?

The question of whether MIPS really works is a complicated one with different research bodies and MIPS itself making various claims around the effectiveness of the safety system.

MIPS’ own testing

A lot of MIPS’ time is dedicated to testing its technology in its own laboratory. In fact, testing has been core to MIPS’ activities right from its inception. When I spoke to MIPS it was just about to pass 48,600 completed tests.

MIPS’ own testing shows that a helmet fitted with MIPS leads to a significant strain reduction compared to the same helmet without MIPS.

MIPS measures the strain caused by an impact by using dummy heads that have the same kinematics as a human head and are fitted with six accelerometers.

The dummy heads are used in a variety of tests, including dropping the heads from a height of 6.2 metres per second onto angled surfaces.

The tests are recorded with high-speed cameras to ensure consistency across tests, so unexpected outcomes can be analysed.

The data recorded by the accelerometers is then fed into the company’s FE (finite element) model of the head and brain, which can model what would happen in a crash.

“For each impact, we save 1,875 data points per accelerometer,” says Seyffarth. “So there’s a lot of data we put into the FE model, and we do a step-by-step millisecond simulation if this had been an actual human having that impact.”

MIPS

Seyffarth says any helmet available on the market with the MIPS yellow dot has been tested by the company and passed the standards it requires for release.

“Whenever we are releasing or approving a helmet for production, we have an internal protocol where we require at least a 10 per cent reduction in strain in every impact location, every helmet and every size.

“But that’s the minimum. We see everything from 10.1 per cent to 75 per cent reduction in strain. I would say the most common is somewhere in the area of 25 to 30 per cent reduction in strain.”

You might argue that a 10 per cent reduction doesn’t seem like a lot. But if you imagine the scale of brain injury as starting with a steep section and then proceeding to level off, you can begin to see how that 10 per cent is critical and, as Seyffarth says, can be the difference between riding tomorrow or not.

MIPS is keen to stress it can only really verify the system is safer in the lab conditions.

“Every helmet is different, every accident is different and every person is different,” Seyffarth explains. “So when we test helmets, we test them in an isolated way to make sure our system works.

“We look at the actual number when we approve a helmet, but the absolute numbers might differ between different helmets and helmet brands.

“Whenever we approve helmets, we only use data from the same day. We would really like to have helmets made from the same batch, in the same exact humidity, and all that, so we get rid of as many factors as possible.”

Seyffarth says comparing helmets isn’t like comparing “apples to apples”, and this is why MIPS will never claim one helmet to be 30 per cent safer than another, for example.

External MIPS testing

But what do other people say about MIPS safety?

Virginia Tech tech has tested over 130 cycling helmets across all disciplines since 2019 and MIPS-equipped helmets have consistently dominated the top rankings, with the top ten helmets in the road, mountain bike and urban helmet categories all featuring the tech.

Folksam, a Swedish insurance group, came to similar conclusions about MIPS with its 2020 helmet test. In total, eight helmets were given Folksam’s “recommended” label, and five of these were fitted with MIPS. It said that the eight helmets performed 18 to 76 per cent better than the average helmet.

Others, however, disagree on the effectiveness of MIPS.

The Bicycle Helmet Safety Institute says its testing “has shown that MIPS does reduce rotational acceleration. But when the head is constrained – as by a neck – MIPS does not perform well. That does not happen in the field, where heads are attached to the body. We still think your helmet, with a normal scalp under it, will move anyway.”

The institute has published a response from Halldin on the same page where he says: “We do have more than 17,000 tests done in Sweden showing that all helmets with MIPS are significantly better than helmets without MIPS. We do have scientific evidence that a helmet with a low friction layer will make a difference in a test including a tangential force.”

Do I really need MIPS and is it worth it?

Extra safety is no bad idea in our eyes, and MIPS builds a convincing case for why taking measures to protect yourself against rotational impacts is wise.

While MIPS technology often tends to add extra cost to a helmet, it isn’t a huge increase in price and there are a number of helmets with MIPS for under £100.

MIPS alternatives

Jack Luke / Immediate Media

There are a number of alternatives to MIPS that also protect against rotational impacts, with brands opting for in-house solutions to rotational impacts, such as Kask’s WG11 rotational impact test and POC’s Spin technology (although POC is transitioning to MIPS across all of its helmets).

Many helmets with these alternative systems rank just as well as other MIPS helmets in testing, and sometimes better.

One alternative system is Bontrager’s WaveCel technology, which has been said to reduce rotational forces by 74 per cent and be 48 times more effective in preventing concussion compared to helmets without it.

WaveCel’s inventors, Dr Steve Madey and Dr Michael Bottlang, authored a study claiming WaveCel is safer than MIPS.

“WaveCel,” says Sam Foos at Bontrager, “is a collapsible cellular material that is designed to be more effective than traditional foam helmets in protecting your head from injuries caused by certain cycling accidents. It works by going through a three-step change in material structure to help absorb the rotational force of impact before it reaches your head.”

Foos also says that WaveCel-equipped Bontrager helmets have been given “top honours” by Virginia Tech.

But Bontrager doesn’t just use WaveCel, with the brand opting for MIPS in some of its helmets too. When asked why, Foos said Bontrager “offers a range of products that align with riders’ needs and combine the best balances of performance, comfort, price, and style.”

There are factors beyond safety that influence which technology is used, then.

Outdated safety standards?

One of the most common responses to the question of why a helmet does not have safety features that protect the wearer from rotational impacts is that the helmet already exceeds the required safety standards.

However, the standards for helmet testing and safety currently set out by the European Committee for Standardization (CEN) do not include rotational force parameters. This means a helmet does not have to be tested for its protection against oblique angle impacts to be approved.

Halldin is part of a working group to change the safety standards to include testing of rotational impacts across all bicycle helmets.

“We are proposing – as a complement to the current standard – an angled impact where we drop the free-falling head form at a 5-degree impact angle to the surface.”

Others, such as Lazer, have come out to say they support rotational injury standards and, beyond cycling, FIM (Fédération Internationale Motorcyclisme), the motorbike racing equivalent of the UCI, also wants to make it part of its testing.

Halldin says the ball is already rolling and we will likely see updated standards in a few years.

In theory, this could mean that some helmets do not pass the safety standards and will need to be redesigned. But Halldin says: “you could probably pass the test without a system like MIPS, as it will be a lower standard. But I think it’s important that the safety standard includes rotation anyway.”

Best helmets with MIPS

Best road bike helmets with MIPS

• Bell Avenue MIPS: £65 / AU$120
• Specialized S-Works Evade with Angi: £230
• Bontrager Circuit MIPS: £100 / $160 / AU$200 / €150
• Giro Helios Spherical: £230 / $250 / €250
• Scott Centric Plus: £150 / $200 / AU$300 / €200

Best mountain bike helmets with MIPS

• Lazer Chiru MIPS: £60 / $65
• Smith Mainline: £275 / $300 / €300
• Smith Session MIPS: £140 / £160 / €160
• Troy Lee Designs A3: £200 / $220
• Troy Lee Designs D4: £500

Best MIPS road bike helmets

Many of the best road bike helmets use MIPS technology, and this is our pick of five of the best, as rated and reviewed by the BikeRadar team.

Bell Avenue MIPS

5.0 out of 5 star rating

Dave Caudery / Immediate Media

• £65 / AU$120 as tested
• Low price and user friendly
• Not that light

At £65 / AU$120, the Bell Avenue MIPS is one of the most affordable helmets with MIPS safety technology.

This lid is user-friendly, too, with easy adjustment on the dial retention system and the glides on the straps make getting the fit around the ears simple.

It’s not the lightest, but the weight penalty is justifiable considering the safety you get for the price.

• Read our full Bell Avenue MIPS helmet review