“That’s not sweat, that’s your fat crying,” Justin encouraged while we ran shuffle relays along the Embarcadero in front of the Cupid’s Span sculpture in Rincon Park. In between burpees, laughs, high fives, and some sight seeing, my fat cried a lot.

Inspired by popular ride sharing programs, self-titled “Sweatreprenuers” Raj Kapoor, Paul Twohey, and Tony Horton set out to disrupt the big box gym model by empowering local trainers. After interviewing over 500 trainers to become "mob leads," Fitmob launched in January of 2014 hosting flash mob-style group exercise classes around the Bay Area.

In an effort to provide “the most complete fitness experience around,” CEO Raj Kapoor extended the Fitmob platform to include access to both studio classes such as Pure Barre and TRX Training Center and gym partners including FitnessSF and Studiomix, with an unlimited monthly “All You Can Sweat” passport.

Fitmob is tailored for fitness grazers who like to try different studios, pop in a gym, and explore Fitmob-exclusive classes. Mobbers can sign up for available classes on the app and website, review classes, view user profiles, and share experiences through social media. If your workout style is dictated by a routine where you must attend specific classes on certain days and at exact times, Fitmob may not be the best fit.

While studios and gym access offer flexibility and variety, it’s the Fitmob-exclusive classes—including Justin’s afore-mentioned “T&A All the Way!”—which emphasize community and a “fat crying” burn that really draws members in. With names like Weapons of Ass Reduction, Time Attack, Sweat Soiree, and Battle of the Bands, you'll want to consult the app and website to know exactly where you will be burning and who will be setting you on fire.

As a first time mobber, I was excited and nervous at trainer Holly’s Lyon Street Slimdown. That was before the mild panic set in when I realized I would be doing seven trips up and down the stairs. That is, in between sets of pushups, triceps dips, and planks. When Holly asks if everyone ate breakfast that morning, you begin to wonder if coffee counts.

Mob leads like Justin and Holly are able to seamlessly cater to a variety of fitness levels within a class but it’s worth checking out class difficulty ratings and user’s feedback on the Fitmob app in advance. After all, what goes down the Lyon Street Steps, must come up.

While the current mobber community is approximately 70% female, the workouts are gender neutral and can leave both the newest and more experienced fitness enthusiasts sweaty and deserving of a second helping of dessert.Both my fiancée and I made Justin’s wish come true, as we found ourselves thinking of him every time we sat down and stood up that weekend.

Fitmob’s monthly $99 passport includes unlimited Mob Exclusive classes, participating studio classes and gym partner access in your city, currently offered in San Francisco and Seattle.

GEAR

• For outdoor classes, wear layers, you’ll warm up quickly but it’s nice to have long sleeves to start. Most classes are held rain or shine so check the weather before heading out.

• Some workouts will have you on the ground or grass, so dress for dirt and avoid light color pants.

• Bring water and a small towel. Studios and gyms may offer water and refills but not all parks have easily accessible water fountains.

• For outdoor classes avoid bringing valuables or keep them in your car. Mob Leads will watch your items or carry them for you but be nice and try to pack light as they may be carrying them up and down Lyon Street Steps. Thanks, Holly!