Ten minutes of ab intervals are a killer. Chipper Brit Rebecca-Louise Smith cheers you through the moves, making it slightly more bearable. Jillian Michaels is scary — but you can’t deny good results. Five sets of these plank-based holds strengthen your core and enhance balance. Tracy Anderson targets love handles the hard way. Even one set of her leg exercises is no walk in the park. See more feel-good films (healthy recipes, organic face masks, muscle-toning moves) on our YouTube channel. Then gear up and get out there.