He knows how the brain warps on impact
When alpine stars crash and hockey players collide at full speed, most viewers gasp at the drama. Svein Kleiven sees something more. As a professor of neuronics at KTH Royal Institute of Technology, he has spent nearly three decades studying how the brain is injured, and how the right protection can prevent lasting damage.
With the Winter Olympics underway, millions are glued to their screens. Behind the medals and celebration, however, lies another reality: high speeds, violent impacts and the ever-present risk of injury.
During the opening days of the Games, audiences held their breath when alpine skiing star Lindsey Vonn crashed heavily just 13 seconds into a downhill run.
Kleiven was watching the same broadcast as everyone else – but through a different lens.
“Downhill skiing at speeds of up to 140 kilometres per hour is brutal,” he says. “It was painful to see Vonn’s fall. And as a researcher, I’m struck by how little development we’ve seen in areas such as ski bindings or protection against knee injuries.”
The overlooked field of prevention
Injury prevention in sport remains underdeveloped, Kleiven argues.
“Modern cars are equipped with advanced sensors and sophisticated protection systems. Sports helmets and other protective gear, by comparison, have changed surprisingly little.”
Kleiven’s research group is internationally recognised for its advanced computational head models, detailed simulations that recreate what happens inside the brain, down to the cellular and molecular level, during different types of impacts. Using these models, researchers can compare how the brain responds with and without protective equipment.
One key insight stands out.
“The brain is particularly sensitive to rotation,” he explains. “Rotational motion causes the greatest stretching of brain tissue and therefore the most severe injuries. And in reality, impacts are rarely perfectly straight. Most involve some degree of rotation.”
From KTH research to helmets worldwide
Addressing rotational forces has been one of the major breakthroughs in helmet design. MIPS technology, now integrated into most modern helmets, was founded 25 years ago by KTH researchers Peter Halldin, Svein Kleiven and Hans von Holst.
The system consists of a low-friction layer inside the helmet that allows it to slide slightly relative to the head during an angled impact. This small movement reduces the rotational forces transmitted to the brain.
Together with Halldin, Kleiven has also collaborated with Swedish alpine legend Pernilla Wiberg and served on the International Ski Federation’s equipment committee. The researchers reconstructed several serious crashes in Kitzbühel to better understand injury mechanisms.
“There have been some extremely violent falls there,” he says. “In certain downhill jumps, skiers can reach heights of five to six metres, roughly the equivalent of jumping from a third-floor balcony, before landing on snow.”
Fifteen years ago, however, it was difficult to convince manufacturers to adopt new safety solutions.
“At the time, helmet producers were conservative, probably for cost reasons. A standard helmet is mainly expanded polystyrene – essentially 95 per cent air and a small amount of plastic, and manufacturing costs are low. Today, attitudes have shifted. Many alpine helmets now incorporate rotational protection.”
Other safety innovations have emerged as well. Some back protectors now include airbag systems, and downhill suits are reinforced with Kevlar to guard against the razor-sharp edges of skis.
“But we still lack sufficient biomechanical research to fully understand injury mechanisms,” Kleiven says. “Without that knowledge, it’s difficult to properly evaluate how effective new protective equipment really is.”
The next step in helmet design
Kleiven is currently developing a new type of rotational protection system for helmets, known as KUL, which uses movable ball bearings to create low friction during impact.
“Our tests indicate that this prototype could reduce concussions by up to 90 per cent,” he says. “That would be particularly relevant in sports such as ice hockey and American football, where concussions are common and can contribute to long-term brain degeneration.”
Progress, however, is slow.
“Preventive research doesn’t attract much funding,” he notes. “But doctoral students are moving the work forward step by step.”
A researcher and a fan
For Kleiven, the Winter Olympics are both a reminder of why his research matters and a source of genuine enjoyment.
“During the Olympics, I’m a complete TV nerd,” he says. With Norwegian roots, he occasionally faces a dilemma when choosing whom to support. Hockey, downhill skiing and cross-country skiing are his favourite events.
“If Sweden and Norway were to meet in hockey, I’d probably have to support Norway. But that will never happen,” he laughs.
Text: Anna Gullers