The blood disorder related to sickle cell disease can cause complications if an individual is under physical stress in extremely hot weather or in environments with low oxygen, such as the high altitude in Denver. Sickle cell trait is a genetic abnormality which can affect red blood cells.
"With my sickle cell, I have no idea if I’ll play there," Coleman told ESPN.com. "I really don’t know how I’ll feel or how it will be like. I’ve never been to Denver."
Former NFL player and current ESPN analyst Ryan Clark, who also has the sickle cell trait, had an episode with the Pittsburgh Steelers (2007) where he became gravely ill and lost his spleen and gall bladder after playing in Denver. Clark was then held out of two subsequent games in Denver, including a playoff matchup.
"It does make me scared a little bit, a little nervous, because I’m risking my life," Coleman said, referring to Clark’s experience. "We’ll have to see. I’ll have to talk to coach [Dan Quinn]. I guess coach will see how I feel when we get there. And I just have to communicate with him, if I am out there [playing], if I’m dead [tired] or can’t breathe. We just have to play it smart."
Coleman was pulled from the end of an August practice as result of extreme heat.
"I was just dehydrated," Coleman said. "I’ll probably get a lot of fluids in me and an IV while I’m in Denver. I will be hydrated so that helps a lot. That will be a step that I take."
Coleman plans to do more research on the matter before the trip. The Falcons could simply limit his reps in the game.
"I know myself, and I know how it will affect me, but I’ll do a little more research of how it is in Denver because, like I said, I’ve never been there," Coleman said. "I’ve never been nowhere with high altitudes."
There is no doubt Coleman would be disappointed if this causes him to miss the game.
"It would bother me quite a bit," he said. "I’d be real upset because my team is going to be out there, and I want to compete and battle for my team. Watching them play, you just want to be out there and ball with them. I’d be really disappointed if I can’t play, but I’d understand because things could happen."
Coleman has been a major factor in the Falcons’ 3-1 start while sharing carries with starter Devonta Freeman. Through four games, Coleman has 129 rushing yards and four rushing touchdowns on 40 carries. He also has 13 receptions for 181 yards.
The Falcons currently have just two running backs on the active roster in Freeman and Coleman. Terron Ward is on the practice squad but could be elevated if Coleman is unable to play. That would also mean a corresponding roster move.
The Falcons already have to tweak the roster with cornerback Jalen Collins, who is expected back after he was suspended the first four games for violating the league’s policy on performance-enhancing substances.