Newswise — Each year, a significant number of individuals in the United States sustain concussions while participating in sports activities. Among these sports, American football players face a particularly elevated risk of enduring injuries that may result in severe long-term effects. In collaboration with Savior Brain, a research team from Stanford University has recently developed a promising solution to safeguard players: a helmet incorporating liquid shock absorbers. This innovative technology has the potential to diminish the impact of head impacts by up to 33%.

"Our team is driven by a strong personal commitment to addressing traumatic brain injury and prioritizing the long-term brain health of athletes," stated Nicholas Cecchi, the lead author of the study published in Frontiers in Bioengineering and Biotechnology and a PhD candidate at Stanford University. "Concussions and repetitive head impacts continue to pose significant challenges in contact sports, and we firmly believe that enhancing helmet technology can significantly contribute to minimizing the risk of brain injury."

HARM reduction

In previous studies, researchers from Stanford University's Camarillo Lab proposed that using liquid shock absorbers in sports helmets could enhance protection. To explore this idea further, the team created a computer model of an American football helmet with 21 liquid shock absorbers. This model, commonly used by engineers to simulate performance before production, was then tested against simulations based on the performance evaluation standards used by the National Football League (NFL). The team compared the performance of their helmet to four existing helmet models. Recognizing that even impacts that don't cause diagnosed concussions can still lead to serious health issues over time, the researchers incorporated lower velocity impacts into their evaluation. For each impact, they measured the movement of the head and calculated a score called the Head Accelerate Response Metric (HARM), which helps assess how well the helmet performs under impact. Additionally, they used the recorded head movement data to create a model of the head and brain to analyze the strain experienced by the brain as a result of the impacts.

Reducing impact by 33%

The findings revealed that the helmet incorporating liquid shock absorbers displayed a significant decrease in the severity of head impacts and the strain experienced by the brain, potentially leading to a substantial reduction in injuries. In comparison to existing helmet models, the liquid shock absorber helmet outperformed them by achieving the lowest Head Accelerate Response Metric (HARM) value in 33 out of 36 different impact scenarios tested. On average, it demonstrated a one-third reduction in the HARM score. Furthermore, when considering the NFL's annual helmet safety rankings, which account for how well a helmet safeguards against impacts in various regions of the head, the liquid helmet received the highest 'Helmet Performance Score.' The most critical area, the 'side upper' portion of the helmet, where concussions are more likely to occur, experienced a 39-50% decrease in the HARM score across all impact speeds, while still maintaining protection in other areas of the helmet.

Dr. Yuzhe Liu, the corresponding author and former postdoctoral scholar at Stanford University, explained, "The incorporation of liquid technology resulted in an average improvement of over 30% in reducing brain loading from both low and high-velocity impacts. This innovation has the potential to significantly diminish the strain experienced by the brain during various types of American football collisions."

The team has ambitious plans to enhance the model's effectiveness in safeguarding players by making notable advancements, such as improving the facemask and chinstrap components. Additionally, they aim to transform the model into a tangible helmet that can be tested in real-world conditions. Furthermore, their long-term objective involves creating similar helmets for various sports. However, it is important to consider that assessing different levels of play or sports may require unique metrics and design modifications.

"Our team's immediate focus is to transform the computer model into a tangible prototype," explained Cecchi. "Once we accomplish that, we aim to conduct human studies that can provide evidence of either a decrease in concussions or a reduction in the severity of sub-concussive impacts. We have additional plans to extend the use of liquid shock absorbers to other regions of the helmet and explore their application in various helmeted activities. By doing so, we aim to enhance brain safety for diverse populations and scenarios."