Today, retired from the ring, he's sharing what he knows with dozens of others. Not would-be boxers.
He's using boxing training techniques as a fitness regimen. It's not for the faint-of-heart. DeMalavez told Action News his goal is to do everything to develop endurance, coordination and strength every session.
His clients get an intense workout he oversees personally. There's no gentle encouragement or one-at-a-time exercises.
Classes are never more than ten people andare pushed to their limit each and every time. He won't let someone enroll in more than three per week.
The training gear looks familiar to anyone who's ever seen a boxing film. In his gym, DeMalavez has participants warm up, then go through a rapid rotation of exercises.
Most require boxing gloves. What the classes don't involve is actual boxing. So men and women work out side by side.
At the end of an hour or so, they've had a complete session that produces results.
One man we met has been a participant for a year and has lost 55 pounds. That's due in part to better eating, but mostly to persistent, weekly training.
DeMalavez keeps watch over his students, paying attention to when someone's likely to quit and barking encouragement to finish the routine.
The participants say they feed off one another's energy and benefit from the team spirit. Like man fitness centers, Joltin' Jabs offers a number of packages.
The more sessions you buy in a bundle, the more you save. The center is at 4303 Main Street in Manayunk, just off the Schuylkill Expressway.
For information, phone 215-482-4802, or visit them online Joltin Jabs.