Every Monday and Wednesday morning for the last two decades, Jack Holleman has been leading a fun jazzercise-throwback-era Hi-Lo exercise class at the Downtown Oakland Y. Not only does Holleman give you a great workout, but the former Marine knows everyone in the class by name, and often calls on the regulars, and even some of the newcomers, to come into a circle and lead a routine. One participant said that the class feels like “attending a friend’s wedding and having a DJ play while you’re dancing.” The class has been together for so many years, that many often even party together on weekends, going to group BBQs, fundraisers, bike rides, and attending each other’s weddings. Speaking of that, Holleman married one of the women in his Boot Camp class several years ago. His wife, Ellen Goldstein, usually ends the Hi-Lo class with sit-ups and crunches.