Chris Johnson, a former running back with the Tennessee Titans, New York Jets and Arizona Cardinals who once rushed for more than 2,000 yards in a single season, revealed in a television interview Monday that he has been diagnos ed with ALS.The 40-year-old Johnson, who last played in 2017, said on ABC's "Good Morning America" that he had been diagnosed with the disease last year.RELATED STORY | FDA approves Biogen's drug for rare form of ALS"We hoped it was something else, but after thorough testing, they finally came down with a diagnosis of ALS," said Johnson, who used a speech-generating device to speak during the interview.ALS, often called Lou Gehrig's disease, is a nervous system disease that affects nerve cells that control muscles throughout the body. The disease leads to muscle weakness and other symptoms that get progressively worse.FROM THE ARCHIVES | High-tech software is giving a voice to those with ALSJohnson said he was sharing his diagnosis because if it helps "even one person" get diagnosed sooner or gives another family hope "then it's worth it.""I still think the same. I still dream. I still love my family," he said. ...read more read less