WaveCel is a compressible cellular material on the inside of Bontrager WaveCel helmets. It was developed by Dr. Steve Madey, orthopedic surgeon, and Dr. Michael Bottlang, biomechanical engineer. They have been working together for over 25 years and have pioneered the field of fracture treatment, thoracic and pelvic trauma and head injury prevention. The Bontrager WaveCel helmets are the result of a four-year collaboration between Dr. Madey and Dr. Bottlang and the Trek and Bontrager Research & Design teams.

Trek and Bontrager report on the new helmet technology: "Conventional foam helmets protect in the event of an impact from above, without lateral movement. WaveCel, on the other hand, takes into account the way most bicycle accidents actually happen - ungracefully, with rotational movements and an oblique impact. WaveCel can absorb the impact energy in multiple ways. On impact, the layers of WaveCel material move independently and can deform until the cell walls are completely compressed, then shift laterally to actively absorb the direct impact energy and rotational energy and dissipate it away from the head."

trekbikes.com