It was exactly 105 days ago that the 2015 San Diego Chargers convened for the last time, already talking about the mindset necessary to rebound from a 4-12 campaign when they returned for the 2016 campaign.

That return comes today with the start of the voluntary offseason program.

While coaches are limited to interactions in the classroom, Phase I is focused on strength and conditioning, as well as physical rehabilitation.  The Bolts add new wrinkles to the program each year, and the changes for this season were done with one purpose in mind.

"We're going to push the players in different ways, and we're going to challenge them," Head Coach Mike McCoy said.  "We all know there are certain improvements we have to make.  We are going to challenge the players physically, mentally and in a lot of other areas, too.  We've always done that, but the way we do it this year will be different in certain ways.  Every year there are changes we are going to make, and that doesn't just include players and personnel.  It also includes the way we do things."

Strength and Conditioning Coach Kent Johnston oversees most of Phase I, and expanded on what the players should expect.

"We're going to push the guys in ways they may not have been pushed since their college days," he said. "Everything will be in accordance with the CBA of course, and will be done in a safe environment. You won't see a big difference in terms of physicality, but I've got to raise the bar as a coach.  I am going to expect more of them this offseason, and some of these guys are going to be pushed to their limit. The guys have always done whatever we've asked, but this year we're going to push them to the brink in safe drills in the context of what they have to do. Our players' work ethic has never been an issue.  These guys work their tails off. They are blue collar, hard workers whenever they take the field or the weight room. My job is to coach them and motivate them, and we are raising the bar this year."

According to Johnston, strength and conditioning goes far beyond physical toughness.  Equally important, he's focused on making the Bolts the most mentally tough team in the NFL.

"My goal personally as a coach is very singular; when we line up to play our first game of the year, our guys are confident and know there is nobody more mentally tough in the league than the San Diego Chargers. There is a big difference between physical toughness and mental toughness. You cannot improve mental toughness as a man unless you push through a barrier that you previously didn't think you could get through.  So our goal these next few weeks is to push our players in ways they perhaps didn't know they could get to.  That is how you build that toughness."

That is also how you build a team.

Entering his 18th NFL season and fourth as head coach of the Chargers, McCoy knows how important chemistry is in a locker room.  He also knows it doesn't begin in training camp, but rather from the very first day of the offseason program.

"That is without a doubt one of the most important things," he said.  "How quickly can we become a team? This is a physical game, so mental toughness is very important. We are going to play in some adverse situations.  There will be some hot and humid situations.  We are going to need to put together some long drives to win a game. So being a team and having mental toughness is about coming together and finding a way to pull through it.  If you can't fight through the adversity, you'll struggle. So you have to be mentally tough to fight through it whatever it is."

Just like with every coach, McCoy relies on Johnston and Assistant Strength and Conditioning Coach Rick Lyle to find new and improved techniques to stay ahead of the curve.  In this field, that includes injury prevention and rehabilitation.

"I always ask what (Johnston and Lyle) think we can do to improve our football team.  There is new research that comes out every year, and what you are looking for changes from year to year.  Last season, we had an unusually high number of high ankle sprains.  So we looked a lot at that. Is there new equipment we can add?  Are there new exercises we can incorporate? Kent is always someone looking to see if there is something we can do better or differently, just like any coach is with his position.   He's always looking for the next step or pieces of technology that will help our players and the team."

As a result, Johnston travelled the country looking for new techniques and techniques to add to the program, including ways to improve injury prevention and recovery.

"Coach McCoy, and really the whole organization, is top notch when it comes to that.  I've been traveling and visiting with people about not only how to treat injuries, but the prevention of them.  We do this every year. There are things we pick up every year that make sense, so as we build toward our season, there are a couple new things we are going to do. There are always going to be injuries, but you try to remedy the things you can remedy and need to always be looking for new techniques and technology."

While the Bolts will be pushed in new ways, that should still expect similar workouts to previous years.

"We will be doing a lot of what we've always done, but we're raising the bar" Johnston explained.  "I want to be clear that this has nothing to do with how our players have worked in the past, because they have always worked extremely hard and pushed themselves.  But I am fired up because we were 4-12 last year, and nobody is satisfied with that. I don't want that to ever happen again.  Everyone is focused on their part, and I am focused on my part.  As I evaluated everything we learned when I came back from the road, I came to the conclusion that we have to focus on the basics.   We've always done it, but I think it is more important than ever, so that is what I am focused on. I think leaders are going to emerge.  I think the players will love it because they are competitors."

So what are those basics Johnston is focusing on?

"First and foremost, and like I mentioned, I think that means mental toughness.  I think that has evaporated around the league. The second thing is sticking with core workouts that help each individual player.  What makes you the strongest?  What makes you the most powerful? What makes you the most agile? What makes you the fastest?  More than ever, I think it is focusing on what works best for each individual, and it is focusing on what makes sense for each position.  Obviously, a wide receiver needs to be more agile than an offensive lineman, so we'll have them focus more on that.  It is what works for the individual.  Guys who can squat will squat, because there is no better way to build lower body strength. If a guy can't squat as well, we're not going to make him.  But we'll find an exercise that works for him, and we'll challenge him."