In gyms everywhere, high-intensity interval training replaced hour-plus cardio sessions. The prevalence of these short, full-body circuits is most evident in the popularity of CrossFit's intense, minutes-long "workouts of the day." "Shorter workouts allow greater intensity," says Ryan Halvorson, senior editor of 'IdeaFitness Journal.' "That's why marathoners can be gaunt or plump, while avid CrossFitters tend to be lean and muscular."
Credit: Getty Images
Powered By ZergNet
The New NFL
Andrew Luck and the Super-Athletes Making Football Faster, Meaner, and More Fun
Plus: A New Approach to Heart Health
ON NEWSSTANDS NOW
Building Haiti's Dream Team: Basketball's Biggest Longshot
The War on Sharks
Sign up to receive the Men’s Journal newsletter and special offers from MJ and its marketing partners.