HARRISBURG - Nine in the morning at the Explosive Sports Performance facility is also known as 'go to work' time.
Its when NFL players and prospects stretch; lift weights and run around -- all to get stronger and faster.
And working right alongside these twenty-somethings?
Marshall Sacks, who's almost 60-years-old; and could be the father of these players -- or even a grandfather. "I just feel you get one body; and you might as well do the best you can to take care of it," said Sacks.
That is Marshall's motto -- and he mans up when it matters. He does leg squats, rope battling, and the box jump; with a box that's 30 inches high.
Marshall's not training for football, though. He just wants to stay in shape; but the players love having him here.
"Like early morning today, I didn't really feel like going out there," said Mike Cox, a graduate of Red Land High School who is now a fullback with the Atlanta Falcons. "I see Marshall jumping over boxes and I know I've got to pick it up."
"To see him come in here and work out hard...keep going at it and don't quit, it gives me motivation; (to say) 'Well, I can't stop,'" said Troy Epps, a former defensive lineman at the University of Florida, who is hoping to catch on with an NFL club as a free agent.
Pushing himself is nothing new for Sacks. He's been a bike rider, runner, and a triathlete. He also credits yoga for his well-being; but at Explosive Sports Performance, he does not receive much of a senior discount.
"The only thing I tend to do a little different; I tone it down (for him)," said Dave Brixius, the founder of the ExSP, who has also helped develop wide receiver Marques Colston of the Saints and Colts lineman Jaimie Thomas. "I check with him more or less; 'How are you feeling?' 'Is everything good?' 'Is anything sore?' Stuff like that."
Even at 59-years-old, Sacks still trains 90 minutes a day, three-days-a-week. He's also still working; as an accountant in Harrisburg.
The big football players surrounding him hope in some small way, they inspire Marshall, as well.
"I'm sure he has that kid inside him saying, 'I can't let them out do me!'" joked Matt Cox, who's hoping to follow his older brother Mike's footsteps and make the NFL as a fullback after being named a Division II All-American this past season at Bloomsburg.
In Marshall's mind, though, one doesn't have to take on the pros to work up a good sweat.
Any time is a great time to get in shape.
"It's never too late to start, wherever you are; just get started," he said.
"Just do something."