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 15: Time for Results
Week three piles it on, to take advantage of your now-high metabolism. This is the place you'll get the most results, so make room in your schedule – you have to spend at least two hours in the gym every day. When you find free time, rest. Every weight workout now includes full body, and there's morning and evening cardio.
*For examples of these exercises see our Summer Fit Workout cheat sheet.
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