Trainers say circuit training is the most efficient type of workout you can do (plus: 3 example workouts)

It combines strength and cardio into one total body sweat session.

This 20-Minute Core and Conditioning Workout Delivers an Instant Abs Burn

Sample this at-home full-body workout from the Women's Health Build & Burn series, programmed by Obé instructor and functional strength coach Alexandra Mack.
Yahoo

'I Did Metabolic Conditioning For 3 Months And Uncovered Chiseled Abs'

"Hearst Magazines and Yahoo may earn commission or revenue on some items through these links." After a year of reestablishing a workout habit and focusing on strength gains, I was eager to see more ...
Women's Health

Why Metabolic Conditioning Is So Effective For Weight Loss And Muscle Gain, According To Research

Picture this: a dimly lit workout studio, the pounding of sneakers as people furiously push through burpees, all while a coach yells, “Ten more seconds!” as you yearn for that rest period on the other ...