: I knew this boutique cycling studio in Old Town had something to offer when I showed up unannounced for a 9 a.m. class and couldn’t get a bike. Emmy Rigali’s classes are so popular that it’s best to sign up on line the night before. Fortunately, someone bailed at the last minute so I tried the Go Pump workout, which is 40 minutes of cycling followed by 20 minutes of weights. It’s an exhausting (in a good way) combination of cardio and strength training. The studio uses smooth-riding Keiser M3 stationary bikes which have an odometer to give you a real time reading of your speed, calories and watts. No more vague "give the knob a half turn to the right," kind of commands. You can also monitor your heart rate. But don’t be intimidated. Rigali, who formerly taught at the East Bank Club, has an infectious enthusiasm and admits she’s not a cyclist. “To me, it’s like dancing on a bike,” she said. “I really believe I can make everyone like this.” In addition to Go Pump and Go Spin ( all cycling), there’s Go Yo (40 minutes of cycling and 30 minutes of yoga) and Go Squared, 45 minutes of cycling and 15 minutes of core. Starting in June, she plans to introduce Go Run for triathletes: 40 minutes of cycling and 30 minutes of running. One class: $18. Five class card: $75.