Former NFL Running Back Chris Johnson Diagnosed With ALS at 40

Chris Johnson, the former Tennessee Titans running back who set an NFL single-season rushing record in 2009, has been diagnosed with amyotrophic lateral sclerosis (ALS). Johnson, 40, revealed his diagnosis during an appearance on ABC's Good Morning America alongside Michael Strahan, becoming one of the most prominent athletes in recent memory to publicly disclose the disease at such a relatively young age.

Johnson said he first noticed weakness in his right hand last year, when his grip felt off. His condition deteriorated rapidly, and physicians confirmed the ALS diagnosis after thorough testing. He now communicates using an eye-tracking speech-generating device. "ALS has changed what my body can do, but it hasn't changed who I am," Johnson said in the interview. "If sharing my story helps even one person get diagnosed sooner, inspires more research, or gives another family hope, it is worth it."

Johnson played 10 NFL seasons, six of them with the Titans. At his peak, he was among the most electrifying players in the league. In 2009, he rushed for 2,006 yards and set the all-time single-season record with 2,509 yards from scrimmage, earning NFL Offensive Player of the Year honors and first-team All-Pro recognition. Over his career he accumulated 9,651 rushing yards and 55 rushing touchdowns. He was inducted into the Tennessee Sports Hall of Fame in 2024.

His diagnosis comes at an age well below the typical onset of ALS, which most commonly affects people between 55 and 75 years. The speed of his disease progression, he said, has been faster than anticipated. "ALS has continued to progress much faster than I imagined," Johnson said. "I want people to understand just how quickly ALS can attack your body."

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ALS is a progressive neurodegenerative disease that selectively destroys upper and lower motor neurons in the brain and spinal cord, leading to loss of voluntary muscle control, paralysis, and eventually death. Most patients survive 2 to 5 years following diagnosis, though a small percentage live a decade or longer. No disease-modifying therapy currently halts or reverses ALS; approved treatments including riluzole and edaravone offer modest survival or functional benefits at best.

Johnson's case renews attention to an increasingly well-documented association between professional football and ALS risk. A 2021 study published in JAMA Network Open examined 19,423 NFL players who played at least one regular season game between 1960 and 2019, representing the largest investigation of ALS risk in professional football to date.¹ Over a mean follow-up of more than 30 years, 38 players were diagnosed with ALS. The rate of ALS diagnosis was 3.6 times higher among NFL players than age- and race-matched men in the general population, and the risk of death from ALS was nearly four times higher.¹ Notably, risk increased with career length: players who developed ALS averaged 7.0 seasons in the NFL, compared with 4.5 seasons for matched players without ALS.¹ Researchers speculated that repetitive head impacts, which have been linked to TDP-43 proteinopathy, a pathological hallmark shared by both ALS and CTE, are likely a contributing factor, though causal mechanisms have not been established.

Johnson said he was motivated to speak publicly after seeing a physician discuss ALS and potential experimental treatments on television. He expressed cautious optimism about the direction of research. "Right now there isn't a cure, but we are seeing more research, more clinical trials, and more promising ideas than ever before," he said. "Seeing how hard these doctors and researchers are working gives me hope. As long as they are fighting for people with ALS, I am going to keep fighting, too."

Johnson is not the first Titan to face the disease. Former linebacker Tim Shaw, who played for the franchise from 2010 to 2012, was diagnosed with ALS in 2014 and has been living with the disease for more than a decade.

REFERENCES
1. Mez J, Alosco ML, Daneshvar DH, et al. Incidence of and mortality from amyotrophic lateral sclerosis in National Football League athletes. JAMA Netw Open. 2021;4(12):e2138801. doi:10.1001/jamanetworkopen.2021.38801. https://doi.org/10.1001/jamanetworkopen.2021.38801