Gold Standard Abs

The lopsided, cannonball-shaped kettlebell works your core like crazy— sculpting, strengthening, and trimming in ways no other tool can match.

- Jenessa Connor

To look at it, you wouldn’t guess that the simple kettlebell is such a fitness hero—both a superior calorie burner and an ab flattener in one. But thanks to its unique physics, it canelicit more burn and firm than other forms of resistance.

Kettlebell cardio

Typical kettlebell moves are calorie guzzlers. Take the snatch (a one-arm lift in which, from a quarter-squat position, you fluidly move the kettlebell from the floor to directly overhead as you stand, bell flipping up and over to rest atop your forearm). It burns some 20 calories per minute when performed at an as-many-reps-aspossible (AMRAP) pace—the same burn rate of a super speedy six-minute mile run, according to a recent American Council on Exercise study at the University of Wisconsin–La Crosse. (Exercisers in the study did a 20-minute workout consisting of 15-second AMRAP intervals of kettlebell snatches followed by 15 seconds of rest.) “It’s a total-body exercise,” says lead author John Porcari, Ph.D.