Since the rise of the Internet, people have struggled to tear their now-useless phone books in half. Bulk up to succeed where others have failed with today’s Groupon: for $20, you get 20 all-access day passes to Nitro Fitness (a $160 value). All-access passes are valid Monday–Thursday from 8 a.m. to 8 p.m., Friday from 8 a.m. 7 p.m., and Saturday from 8 a.m. 4 p.m.

Inspired by their 20+ years of industry experience, Nitro Fitness’ founders welcome exercisers to a community environment packed with body-firming machines and group classes. Muscles bulk up with Nitro’s brawn-building equipment, flexing through the gym’s circuit machines, heaving heavy objects on the free weights, or tearing increasingly larger phone books in half at the gym’s recycling center. The cardio room sends hearts aflutter with treadmills and ellipticals glowing under the flicker of television screens. Training bods also mingle during group classes such as Zumba, yoga, and kickboxing, obtaining the rosy glow of friendship and the healthy sheen of perspiration. All-access passes also grant exercisers access to Nitro’s other amenities, including on-site childcare, showers and change rooms, the Nitro Grill, and piggyback rides from the gym’s receptionist.