A crash workout is not the best way to get in shape. Eating well and exercising daily over a long period is a much healthier – and easier – approach to getting a body you can live with. But if it's a matter of vanity, not long-term well-being, you can turn your body around fast. "Three weeks may seem last minute," says Ron Mathews, a Hollywood trainer who specializes in high-intensity circuit routines and who designed this 21-day workout for us. "But you just need to maximize caloric output and minimize calorie input while activating as many muscles as possible."
Simple. Grueling. Effective. Here's your plan.
Day 8: Taking Away
Week two is all about taking away: dropping gluten, salt, and booze from your already low-calorie meals. At the gym, focus on alternating muscle groups – chest and arms, back and legs – for maximum impact. On top of this, the cardio gets intense with daily intervals. Mix it up by choosing biking, rowing, or running (see "The Workouts").
- Regular Cardio
*For examples of upper body exercises see our Summer Fit Workout cheat sheet.
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