Many athletes train in high-altitude conditions to accustom themselves to standing atop the first-place podium. Simulate victory with today's Groupon: for $59, you get a high-altitude-simulation training mask (a $90 value), athletic bag (a $20 value), and a hat (a $14 value) from Elevation Training Mask (a $123.99 total value).
Championed by physical specimens such as UFC fighter Sean "The Muscle Shark" Sherk, and utilized for MMA and CrossFit training, the Elevation Training Mask creates more challenging cardio and strength-training workouts by simulating high-altitude conditions. The compact, lightweight mask fits snugly and allows exercisers to continue their standard workout routines and antique shopping with little added encumbrance. Once secure, nozzles at the end of each mask filter the flow of oxygen through the nose and mouth, creating an effect corresponding to training conditions at thousands of feet above sea level. Through repeated use over gradually increasing intervals, lungs respond to this pulmonary resistance by increasing their capacity, and the body produces more oxygen-carrying blood cells while making existing oxygen transfer more efficient through elimination of excessive inter-organ paperwork. After several weeks of use, trainees begin to notice significant improvements in physical and mental stamina when the mask is removed for workouts and competitions. Read about the science behind the mask here.