(AP) -- The hours are brutal, and so are the expectations of millions who sit in judgment of what you do on Sunday afternoon.
Being a coach in the NFL isn't necessarily an automatic ticket to the emergency room. But the hospitalization of two coaches on one midseason weekend- one after collapsing on primetime television - is a scary reminder that the unrelenting pressure of trying to win football games week after week can be a dangerous thing.
"Football sure is stressful and coaching is a stressful occupation - just like a lot of people's jobs are stressful," said Dan Reeves, who underwent heart surgery while coaching the Atlanta Falcons in 1998. "But it's such a time-consuming job that you don't really take care of yourself the way you should, and it's easy to have those things happen."
Like Denver's John Fox, Reeves knew he had heart issues during the season. Like Fox, he wanted to put them off as his team made a run to the playoffs.
And like Fox he ended up in the hospital while his team played without him.
"Good thing I finally said something to a doctor," Reeves said, "or I could have had a heart attack."
Fox underwent aortic valve replacement surgery Monday, two days after feeling dizzy while playing golf near his offseason home in North Carolina. Predictably, the team issued a statement quoting the coach as saying he was disappointed to have to leave the team and looked forward to returning to the sidelines as soon as possible.
Not so predictable is the future of Gary Kubiak, who collapsed while walking off the field at halftime Sunday night in a game his team would go on to lose in his absence. Though the Texans issued a statement saying Kubiak was alert and in good spirits, he will remain in a Houston hospital at least through Tuesday while doctors run tests to find out what caused him to go down.
They're coaches of two teams going in different directions, with one thing in common: Both are suddenly powerless to do anything about it.
"It'll be tough on them, sitting there and thinking they can't do what they are supposed to do, that your job is to help your team," former coach Tony Dungy said. "You really feel that: 'I can't help my team.'"
The timing of the hospitalizations just a day apart was coincidental, though still a bit unsettling to the rest of the coaching fraternity. Kubiak's collapse came after a rare good half of football this season for the Texans, while Fox was enjoying a bye week in a season where the Broncos have done nothing to diminish expectations that they will be in the Super Bowl.
Both make millions coaching in the NFL, but the job comes at a price and with the understanding that winning is the only thing.
"There is a lot of pressure on head coaches," Broncos executive John Elway said. "I think especially with the size of this game and the growth of this game, the expectation levels have continued to grow. So that's a tough, tough spot."
Elway said he called Indianapolis general manager Ryan Grigson on Sunday to see how the Colts managed last year, when coach Chuck Pagano was diagnosed with leukemia and hospitalized. Pagano had been experiencing extreme fatigue and bruising but, like Fox, waited until the team's bye week to be checked out by a doctor.
Pagano would return for the last regular-season game, and the Broncos are already preparing for the eventual return of Fox.
"This is Coach Fox's team," interim coach Jack Del Rio said. "I'm merely the person that's able to keep it running right now while he's healing."
Coaches around the league talked Monday about how they try to deal with the stress of a job that takes place under an unrelenting spotlight. They praised team doctors for making sure they have regular physicals, and said they try to understand the warning signs that come with the job.
Then they went back to their offices to break down film and get ready for another Sunday where 70,000 people in the stadium and millions more at home are second guessing their every move.
"There are times when stress does things to you mentally and physically that nothing else does," said Arizona coach Bruce Arians, who took over for Pagano when he was sick. "I know when I was at Temple my last year, I was having three migraines a week. The day I got fired I didn't have another migraine."
Stress can affect people in different ways, but researchers say there is an expanding body of evidence linking it to increased risk for heart disease, strokes and certain types of cancer. George Slavich, director of the Laboratory for Stress Assessment and Research at UCLA, said it increases inflammation in the body which leads to health problems.
"Stress-related increases in inflammation are a secret killer in the United States," Slavich said. "What we have here is a good example of how stress can affect people in a high stakes, high pressure environment."
It doesn't get any more high stakes or high pressure than the NFL, but coaches everywhere are used to feeling the urgent need to produce. That's certainly true in the college ranks, where the pay at big schools is comparable to the NFL and alumni are every bit as demanding as NFL fans are when it comes to their school's football team.
Urban Meyer went to the emergency room complaining of chest pains the day after the SEC championship game when he was at Florida in 2009, and Wisconsin's Gary Andersen collapsed in the bathroom of his home the next year after a loss while at Utah State. Minnesota's Jerry Kill, meanwhile, had to take a leave of absence this year after suffering a series of epileptic seizures.
Oklahoma coach Bob Stoops knows well the perils of his occupation. His father died in 1988 while coaching a high school game.
"I lost my father in the sidelines at 54-years-old, so if anybody knows the hazards of it, it's myself, my family, and the reason why I yearly, twice a year, am very aware of being checked thoroughly with doctors," Stoops said. "Not that that can prevent it, but you want to use the science, and the medicine and doctors as much as you can."