Like Greenland, the increasingly popular superslow workout isn't quite as idyllic as its name would suggest. A session takes just 20 minutes, and only two workouts a week are expected, but this adds up to a very grueling 40 minutes. Clients cycle through six different weight machines, doing a set of four to six repetitions per exercise. but each rep takes up to 20 seconds, with no rest, so muscles quickly start to quake, and stomachs get queasy. trainers encourage short, sharp breaths in place of squirming and grimacing. "It sounds like a lamaze class with cursing," says lou abato, a new york city trainer. the technique was invented in 1982 by trainer ken hutchins, who believes that other methods can cause injury and provide lesser results. Though Superslow has many skeptics, a study published in the journal of sports medicine and physical fitness showed that beginners had 50% more muscle growth than those who used traditional weight-lifting methods. But after the study, only two of the 147 participants chose to subject themselves to it again.
--By Joel Stein