Log 45 to 60 minutes of steady-state cardio twice a week and at least 30 minutes of interval-based work once a week.
Why it works: If you like long runs and that's all you do, you won’t challenge all of the systems by which your body makes energy. Variety—in workout type, duration, and intensity—activates both the aerobic and anaerobic systems, Delaney says. Steady-state sessions force your body to create its own energy, which boosts metabolism. Higher-intensity training has the same effect but for a different reason: The harder you work, the more calories you’ll burn post-exercise as your body returns to baseline.
Use weights that allow you to max out between 8 and 12 reps two times per week.
Why it works: Working in this hypertrophy rep range increases muscle size and mass, the exact adaptations that trigger a higher resting metabolic rate, Delaney says. “Muscle is energy expensive.”
Swap a processed food in your daily diet (a protein bar, for example) for a whole food.
Why it works: Your body uses more energy digesting whole foods than it does processed items because of their higher fiber content, St. Pierre says. In terms of calories, you burn more breaking these ingredients down and you extract fewer from them. The opposite is true for processed foods: They’re easy to digest and your body absorbs maximum calories from them.
Eat at least one probiotic ingredient every day.
Why it works: The bacteria in your GI tract affects your metabolic rate, St. Pierre notes. In fact, improving your microbiome health through probiotics can help you burn up to 150 extra calories per day. Get the benefits from foods such as yogurt, kefir, kimchi, and kombucha.
Eat a palm’s worth of protein (lean meats, tofu, Greek yogurt) multiple times per day. The ideal range is four to six for women, six to eight for men.
Why it works: You burn more calories digesting protein than you do carbs or fats, St. Pierre explains. Plus, the macro helps you build and hang onto muscle and bone mass. If you don’t get enough protein or you eat it too infrequently (say, one or two large servings rather than smaller ones throughout the day) your metabolism may drag because your body is spending less time working to break down these foods, Delaney says.
Set a consistent sleep-wake schedule and cap high-intensity workouts at three per week.
Why it works: These seemingly disconnected habits are strongly intertwined: Both are crucial for proper recovery, which helps you maintain healthy hormone levels and keep your metabolic rate up, says St. Pierre. If you’re not sleeping well, for example, leptin and ghrelin levels can go awry, making you crave processed foods.