Heat promotes perspiration and burns excess calories, which finally answers the baffling question of why ice shrinks when it sweats. Form your own high-temp hypotheses with today's Groupon to Forever Om Yoga in Lake Forest. Choose between the following options:

• For $40, you get five drop-in yoga classes (up to a $90 value).
For $80, you get a 10-class pack of drop-in yoga classes (up to a $160 value).

Borrowing its name from an ancient meditative chant, Forever Om Yoga turns up the heat on classic Vinyasa flows for calorie-burning, mind-clearing workouts. Aside from warming the studio to between 78 and 98 degrees Fahrenheit, a high-tech heating system cleans and recirculates air with an infrared light, facilitating easier, deeper breaths. In each 75-minute class, Yoga Alliance- and Baptiste-certified instructors lead groups through either gentle, 78-degree Vinyasa flows or hotter, high-energy flows inspired by Baptiste power yoga. The basic yoga class features the essential Vinyasa poses, and a class focused on athletic recovery incorporates therapeutic stretching and twists to help repair sore or strained muscles and prevent future injury during all-night Twister marathons.

Although students are encouraged to bring their own mats, Forever Om offers rentals for an additional fee. Classes run throughout the day; click here for a schedule of upcoming sessions.