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 10: Cut out Alcohol
If you have two light beers every day, you add 1,540 calories and 92 grams of carbohydrates a week. Knock it off.
- Interval Cardio
*For examples of upper body exercises see our Summer Fit Workout cheat sheet.
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