Former NFL player Derek Kennard works out at a gym near Phoenix, Arizona, in 2017. The effects of head trauma have gotten much of the attention, but huge weight gains have also damaged NFL retirees. Kennard has struggled with sleep apnea and weight gain since retiring from the NFL.
(Caitlin O’Hara/The New York Times, file)
Former NFL player Vaughn Parker, who has had ups and downs with his weight after retiring from the NFL, works out in Carlsbad, California, in 2016.
(Brian L. Frank/The New York Times, file)