Research released this week presents stark evidence of the long-term neurological toll exacted by American football, with findings indicating that chronic traumatic encephalopathy affected at least one in four former NFL players who passed away between 2016 and 2021. The study, conducted by researchers at Mass General Brigham, Boston University, and the Concussion & CTE Foundation, examined brain tissue from 235 deceased former players out of 878 deaths during the five-year period, uncovering a troubling pattern of degenerative brain disease among the sport's retirees.
The researchers documented that 215 of the 235 donated brains exhibited evidence of CTE, a progressive neurological disorder characterised by the accumulation of abnormal tau protein in the brain. Unlike injuries that can be identified through imaging during life, CTE can only be definitively diagnosed through post-mortem examination of brain tissue, making retrospective studies of donated brains a crucial window into understanding the disease's prevalence among former athletes. The sheer proportion of affected individuals—roughly 91 percent of the brain donors examined—underscores the severity of the concern and suggests that the true population burden may be significant.
Daniel Daneshvar, who chairs the department of physical medicine and rehabilitation at Mass General Brigham and serves as an associate professor at Harvard Medical School, highlighted a critical epidemiological finding: NFL players experience approximately four times the rate of death from neurodegenerative disease compared to the general population. This elevated mortality rate points to a direct relationship between the accumulated trauma experienced during football careers and the subsequent development of conditions that shorten life expectancy and diminish quality of life in retirement. The discovery extends beyond CTE alone, with researchers noting that dementia was prevalent among brain donors, suggesting a broader pattern of cognitive deterioration affecting former players.
A particularly significant revelation from the research concerns the timing and location of head impacts throughout athletes' careers. Daneshvar emphasised that the cumulative damage resulting in CTE does not originate primarily from professional-level play but rather accumulates across decades of exposure beginning in youth and high school football. The bulk of traumatic head impacts, according to the research, occur during practice sessions rather than actual games, and this pattern persists across all competitive levels. This finding has profound implications for how the sport is structured and managed at grassroots levels, where safeguards are often less rigorous than at professional stages.
The NFL has implemented certain protective measures in response to mounting evidence of brain injury risks. The league's 2011 Collective Bargaining Agreement introduced restrictions on full-contact practice sessions during the competitive season, attempting to limit the frequency of high-impact collisions that players experience. Additionally, the Ivy League implemented a ban on full-contact tackling during practices, recognising that competitive exposure during training poses particular risks. These interventions, however, remain largely confined to elite levels of play, leaving younger athletes and collegiate competitors with substantially fewer protections against repetitive head trauma.
The Supreme Court's 2016 approval of the NFL's settlement with thousands of retired players concerning concussion-related injuries marked a pivotal legal moment, acknowledging the league's responsibility toward former competitors who suffered neurological harm during their careers. Yet despite this legal resolution and growing awareness among medical professionals, systemic changes have been slow to permeate downward through the organisational structure of American football. High school and youth programmes, where Daneshvar's research suggests the foundation for later CTE development is established, continue operating with minimal intervention from higher-level governance bodies.
Daneshvar presented compelling evidence that transformative change need not require eliminating the sport but rather modifying how practice is conducted. Research indicates that nearly seventy percent of all head impacts experienced by players occur during training sessions rather than competition. By implementing practice standards similar to those adopted at the NFL level—reducing full-contact drills to less than once weekly—institutions at collegiate, high school, and youth levels could substantially decrease cumulative head impact exposure throughout an athlete's playing lifetime. The intervention would require no changes whatsoever to game-level competition, yet could meaningfully reduce long-term neurological risk.
The NFL spokesperson responded to the study by reaffirming the league's commitment to player safety, noting ongoing efforts to reduce concussions and head impacts through various strategies. The organisation highlighted its expansion of mental and physical health resources available to former players and current community members, encouraging athletes experiencing cognitive concerns to utilise these support systems. Yet researchers argue that resource availability, while important, cannot substitute for structural prevention at the foundational levels where young athletes first encounter the sport and begin accumulating the impacts that decades later manifest as neurodegenerative disease.
For Malaysian and Southeast Asian sports administrators and medical professionals, this research carries implications extending beyond American football. As rugby, Australian rules football, and other contact sports grow in popularity throughout the region, understanding the long-term neurological consequences of repetitive head trauma becomes increasingly relevant. The study suggests that protective measures—particularly reducing practice-based contact at youth and amateur levels—should be implemented proactively rather than reactively, as evidence of harm typically emerges only years or decades after exposure.
Daneshvar and colleagues have specifically urged current and former athletes experiencing cognitive symptoms—memory loss, confusion, mood disturbances—to seek evaluation from specialists in neurodegenerative disease, emphasising that early identification and management may improve outcomes. The research underscores that the problem of sports-related brain injury is fundamentally a public health issue requiring coordinated response across medical, sporting, and policy institutions rather than individual responsibility alone. The cumulative nature of head impact damage means that interventions must target the entire athlete lifecycle, from youth participation through professional careers, with particular emphasis on the high-impact periods where most damage accumulates.
