“I wish I could tell you my mom made some sort of special pancake mix, or there was some magic sauce we had,” said Cooper Manning, whose football career was cut short by a chronic spinal condition that required surgery. “But you’ve got to be fortunate.”  That may change for Peyton Manning, 35, who had not missed a start since entering the N.F.L. in 1998. On Thursday, he underwent the second operation on his neck since late May, and he may need three months to recover.  Eli Manning, 30, made his first professional start on Nov. 21, 2004, and since then 126 different quarterbacks have started games for the league’s 31 other teams, according to the Elias Sports Bureau.  “I don’t know what my number is,” Manning said of his streak. “You try to be out there every week and perform and be on the field with your teammates. It’s not something that I’m keeping track of.”  Manning has largely avoided taking big hits, which speaks to his protection and his pocket presence, throwing quickly and rarely scrambling. Still, he has had injuries that jeopardized his streak, none more notably than in 2007.  That year, Manning sustained a shoulder injury in Week 1 that was described as a sprained acromioclavicular joint, or AC joint. Publicly, Coach Tom Coughlin played it down. Manning even tried to prove to reporters that he was fine by waving around a pair of shorts in the locker room.  In fact, Manning had sustained a Grade I shoulder separation, according to a person informed of the injury who was not authorized to speak publicly about Manning’s health. The slight separation could have sidelined Manning for several weeks. Instead, he went on to lead the team to a Super Bowl victory over the New England Patriots.  “The quarterback, you can play with a lot of big injuries,” Manning said. “You get a little injury like an index finger or a thumb that most people can play with, sometimes you can’t. I’ve stayed away from some of those.”  Manning’s easy air belies his toughness. David Cutcliffe, who coached Peyton at Tennessee and Eli at Mississippi, recalled seeing the younger Manning walk off the field with his mouth and nose bloodied after he took a hit in a game against Florida his senior year. He did not miss any time.  “He is a tough son of a gun who happens to play quarterback,” Cutcliffe, now the coach at Duke, said by telephone. “I don’t think anybody has any idea. He’s 100 times tougher than he’s given credit for.”  Eli Manning works out, as he did in 100-degree heat with Cutcliffe over the summer at Duke, to prevent the muscle pulls and minor injuries that sometimes slow players. He has also taken better care of his body as he has grown older. He once favored pizza and skipped eating breakfast. No more.  It is not uncommon for Eli and Peyton to steal away to exercise during off-season vacations, just as they did when they were younger. Their companions learn about the brothers’ early-morning run only if they ask about it. It is a measure of discipline that they learned from their father, who at 62 rarely misses a workout.  For the younger Manning, taking over as the consecutive-starts leader is perhaps more symbolic than anything. He may never banish the comparisons that inevitably come with the name on the back of his jersey, which narrows a spotlight on him with each interception or radio-interview sound bite.  But Eli Manning will stand alone on Sunday as the N.F.L.’s new ironman quarterback.  A version of this article appears in print on September 11, 2011, on Page SP8 of the New York edition with the headline: Streaks Built on Preparation, Day After Day. Order Reprints| Today's Paper|Subscribe
As Peyton Manning’s streak of consecutive starts is about to end, his brother Eli, the Giants quarterback, is expected to make his 104th consecutive start.