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 11: Drop gluten
Cut as much gluten (wheat, barley, and rye) and salt as possible. Both cause belly bloat, and by avoiding gluten, you avoid refined carbs, which cause weight gain.
- Interval Cardio
*For examples of back and leg exercises see our Summer Fit Workout cheat sheet.
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