Orangetheory Fitness brings the heat at Minnesota studios

What it is: A high-intensity interval workout that focuses on burning calories. Each 60-minute session is divided into cardio (treadmill and indoor rowing) and strength training. The intensity levels are based on heart-rate zones, with the goal of being able to work out for 12 to 20 minutes at 84 percent of your maximum heart rate — dubbed the orange zone.

Participants may strap on a heart-rate monitor to track their stats, which can be displayed for those who like to compete with themselves or others in the class.

An app allows users to track their past 90 days of fitness.

Trial run: I rarely measure my fitness activity as closely as I'd like to, so the class helped me with that. I also enjoyed the camaraderie. Plus, the upbeat music and the orange lighting kept me pumped up for the entire hour.

Who it's for: People who want a challenge or are stuck in the rut of "I work out often, but I see no results." Each session can be tailored to your fitness level, even if you're a beginner.

Who it's not for: People who dislike cardio.

Do: Arrive early. You can rent a heart-rate monitor or buy your own. Bring a water bottle. You'll be able to sip — or guzzle, as needed — during cool-downs and transitions.

Don't: Worry about measuring up to others around you. Participants work out at one of five speed zones, ranging from mall walking to all out, based on individual fitness levels.

Cost: The first class is free. Then, studios offer basic, elite and premier memberships. Classes range from $8 to $28; average members pay $12.37 per class.

Where: The national chain has six locations in the Twin Cities metro area: Apple Valley, Eden Prairie, Edina, Maple Grove, Minneapolis and Plymouth. Two more gyms are coming to Chanhassen and St. Cloud. ­Go to orangetheoryfitness.com.

Natalie Daher • 612-673-1775 • @NatalieDaher7