Indianapolis Colts v Tennesse Titans

Chris Johnson (No. 28) of the Tennessee Titans is seen during an NFL game against the Indianapolis Colts at LP Field on Oct. 11, 2009, in Nashville. The Colts defeated the Titans 31-9. 

 Photo: Getty Images/Andy Lyons

Former Tennessee Titans running back Chris Johnson disclosed Monday on national television he has been diagnosed with ALS.

Appearing on ABC's "Good Morning America,” Johnson, 40, told GMA co-anchor Michael Strahan (also a former NFL star) that he was diagnosed with the disease in 2025.