It means that he’s not working out with the team, or rehabbing his broken leg with Jets trainers.
According to Rich Cimini of the New York Daily News, Jets coach Rex Ryan doesn’t like it. Per Cimini, Ryan said that Washington is “making a mistake” by rehabbing away from the team’s trainers.
Actually, Washington made the mistake when he didn’t sign the long-term offer that was available before he broke his leg. The mistake is now simply playing itself out, with Washington wanting the contract he didn’t get last year and the Jets not inclined to give it to him and Washington doing the only thing he can to display his displeasure — exercising his right to not show up, even if it’s in his best interests to show up and rehab his leg with the team.