Yoga is a much easier way to exercise both mind and body than testing Einstein's theory of relativity by racing a beam of light. Avoid a science-related sprain with today's Groupon: for $39, you get one month of unlimited yoga classes at Power Yoga Hawaii on Piikoi Street (a $150 value). This deal is not valid for Sunday classes.

Power Yoga Hawaii's knowledgeable yogis Dorian and Lehua guide students toward a state of spiritual insight and tranquility through myriad yoga disciplines. Power yoga, a fast-paced flow, blends breathing with Iyengar and Ashtanga poses, helping to build lean muscles, improve circulation, and develop a perfectly trapezoidal shadow. Prana Flow yoga weaves classical and innovative approaches to Vinyasa flow through balanced and flowing movement that helps improve posture and melt cerebral cloudiness in students of all levels. Meanwhile, Unnata aerial yoga focuses on a peaceful state of mind using low-hanging fabric trapezes, which support the body’s weight and help achieve postural alignment with deeper stretching exercises than can be achieved on the floor or inside a broom closet. And prenatal yoga allows moms in training to prime little ones for a healthy work/life balance while practicing deep breathing and exercise.

Power Yoga Hawaii’s 1,700-square-foot studio houses up to 60 people or human-size papier-mâché creations per class, with class times available morning, noon, and night seven days a week. This unlimited pass is not valid toward Sunday classes; although students are welcome to participate that day, they’ll be asked for an additional donation. A towel and mat are required, both of which can be brought from home, rented from the studio, or stitched together at the beginning of class.