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 4: The Small Meal Plan
Eat five to six smaller meals each day (300 to 400 calories each) and space them two to three hours apart. This causes your body to release less insulin, which prevents you from storing as many calories as body fat.
*For examples of leg and shoulder exercises see our Summer Fit Workout cheat sheet.
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