Planet Fitness

Planet Fitness on Massachusetts Avenue offers cardio and strength equipment near Porter Square, with in-club fitness training included in its memberships. The Classic plan covers this home club; the Black Card plan adds access to other locations and guest privileges, subject to the membership terms. That distinction matters if your routine takes you between Cambridge and another neighborhood.

This location is not open around the clock. It currently opens early on weekdays, stays open until midnight Monday through Thursday, and closes earlier on Friday and weekends. The club page has the full schedule and a crowd-history tool to help plan your visit. Compare annual and startup fees as well as the monthly rate before choosing a plan.