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 $25, you get one 10-class punch card at Bikram Yoga Mississauga in Mississauga (a $160 value).

Bikram Yoga Mississauga heightens strength and flexibility with invigorating, 90-minute hot-yoga classes scheduled seven days a week. Impassioned instructors remix the 26 pliable poses from the Bikram tradition, which awakens the different organs of the body more gently than foghorn alarm clocks. Classes take place in a heated room to protect the body from injury and to elevate metabolism. Sweat-swaddled students can cool down in separate men's and women's showers and changing rooms adjacent to the eco-friendly studio. Use of a yoga mat is not included in this deal, but mats may be rented, purchased, or transfigured from water bottles at the on-site retail shop, which carries brands such as Shakti, Onzie, and Light Activewear.