As one of the most successful coaches in the history of Division III college football, Lance Leipold rarely had players on campus at Wisconsin-Whitewater working out during the summer. Maybe a few would pop in for a weekend or to help out with a summer camp. But if 10 stayed in town for the offseason, it was unusual.

“To have a team fully stay and have a regular program?” said Leipold, who won six NCAA championships in eight years. “Not once.”

Things are different now for Leipold, who has been at Buffalo the past five seasons. Even for a team in the Mid-American Conference, there is no offseason in the Football Bowl Subdivision, where the cycle of postseason drills, spring football and summer conditioning leading into fall camp never stops.

Except during the time of COVID-19.

This indefinite interruption to the way major-college football programs operate has raised a significant question to which there remains broad disagreement across the sport.

When it’s finally safe to bring football players back to campus for regular training, how long would they need before it's safe to start a season?

“We have to get football right,” Dr. Brian Hainline, the NCAA’s chief medical officer, said in a webinar late last week. “Football is an aggressive, rugged contact sport, so we need to be certain players are really well prepared because we don’t want to see all the sudden a number of musculoskeletal injuries or overuse injuries because we brought players back too quickly.”

The problem is, there’s no right answer to how long that will take because there’s never really been a situation like this one.

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Penn State athletic director Sandy Barbour drew raised eyebrows this month when she mentioned on a call with reporters that its staff was looking at a 60-day runway between the arrival of athletes on campus and the start of the season.

That would be a significant length of time, since it would mean college football programs starting their normal operations back up by July 1.

“We’ve relied on our sports science folks, strength and conditioning, our head team physician, to really look at this from a health and safety standpoint,” Barbour said. “And we believe given the amount of time that training has been for football, we think that 60-day window is about right.”

Others disagree. While there is broad agreement that programs will need some type of window before the typical football-focused fall camp to get players up to speed given that nearly all of them are limited in their capacity to work out at home, whether that encompasses two weeks or two months is little more than an educated guess.

“I’m not sure there’s a science-based answer,” said Amy Hollingworth, director of the Safe Sports Network at the New Hampshire Musculoskeletal Institute. “There aren’t a lot of corners you can cut so I think that’s going to be an issue. As much as players can still prepare themselves (at home), they can’t do some of the physical and contact work that they need to do that is used in the preseason. Shortening the preseason would be potentially detrimental to the players and increase their injuries.

“But there’s no playbook for any of this.”

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There are three key components driving some of the angst around this issue.

First is that even in the best-case scenario, coaches expect that players are going to struggle staying in optimal shape while at home under social distancing rules. Schools can supply players with workout programs and simple equipment like resistance bands, but it’s not the same as going in at 7 every morning to a world-class weight room with highly qualified trainers.

There’s also a significant inequity with nutrition, which schools can try to address by shipping boxed meals or protein shakes. But the concern is that many players from disadvantaged socioeconomic backgrounds are not getting the type or amount of food that they need to maintain their bodies.

And finally, assuming players come back in July or August, trying to practice in the heat of summer when they aren’t in optimal shape is a recipe for disaster given what we now know about the risks of heat stroke.

“Heat acclimatization is one of the big changes that has happened in football in particular, and that period seems like it might need to be also lengthened,” Hollingworth said.

While some coaches have said they feel as if they could get their team ready to play in roughly a month, the likelihood is that a plan to bring football back would fall somewhere in the range of six weeks.

But that decision will ultimately have to be made by the NCAA, which has convened a COVID-19 advisory panel led by Hainline, several other physicians and four athlete liaisons.

The six-week time frame lines up with what Ohio State coach Ryan Day mentioned as a “starting point” in a call with reporters Wednesday, meaning a mid-July return to campus would be enough to start the season on time if programs got an all-clear to begin preparations.

American Athletic Conference Commissioner Mike Aresco said the working group it has formed within the league to address this issue led by Cincinnati’s Luke Fickell and Memphis’ Ryan Silverfield has even broken down what each week would look like during a six-week ramp up and submitted it as feedback to the NCAA.

Still, is six weeks too much? Not enough? Nobody really knows the answer, and the only way you might find out it wasn’t enough is if teams get into practice and start having more injuries than normal.

“I won’t put a young man on a playing field and ask him to compete unless he has had the opportunity to be properly conditioned and trained to play this game at the highest level,” Notre Dame coach Brian Kelly said. “Again, I think I’ve made it pretty clear in talking to our training staff and our strength and conditioning staff we’re going to need a proper amount of training necessary from a safety standpoint to play this game. It’s not going to be just a few days, it’s not going to be a week; minimally three or four weeks to prepare our team.”

What everyone agrees on, though, is that it’s going to have an impact on the product. Coaches might have to apportion more time on conditioning than on football, even after the traditional fall practice starts. They might have to limit their playbooks in some way. Inevitably, some players are going to come back in better shape than others.

But coaches like Leipold, who came from a level of football where year-round practice didn’t really exist, will be nimble enough to figure it out.

“At Whitewater, we’d have a conditioning test and a lifting test and get a barometer of where they’re at and work accordingly for those who didn’t pass it, and you just have to find a way to get them caught up and be really smart about it,” Leipold said. “But everybody should be in the same boat as far as a starting date, and as long as that part is consistent I think everybody has a chance to get their teams ready. Will it be the same in the in-depth of what you might have normally? Probably not. But whatever the parameters are, everyone will be excited and we'll get them ready to play.”