Gift Certificate for three classes at Orangetheory Fitness Brighton. Orangetheory Fitness is a one-of-a-kind fitness experience that combines two concepts: heart rate-monitored interval training and group personal training. The one-hour, ever-changing workout was formulated by an exercise physiologist and consists of diverse components, including high-energy cardiovascular and strength training using treadmills, rowing machines, suspension training, and free weights with short bursts of intense exercise.