You can speed up your metabolism through a combination of building muscle, staying physically active throughout the day, eating enough protein, exercising at higher intensities, and getting adequate sleep. No single trick will transform your metabolic rate overnight, but stacking several habits together produces a meaningful difference in how many calories your body burns at rest and during activity.
To make smart changes, it helps to understand what your metabolism actually consists of and which parts you can influence the most.
What Makes Up Your Daily Calorie Burn
Your total daily energy expenditure has three main components. The largest is your basal metabolic rate (BMR), the energy your body uses just to keep you alive: breathing, circulating blood, maintaining body temperature, repairing cells. For most people, this accounts for roughly 60 to 70 percent of all calories burned in a day. The second component is physical activity, which includes both structured exercise and all the smaller movements you make throughout the day. The third is the thermic effect of food, the energy it takes to digest what you eat, which accounts for about 10 percent of your daily burn.
The practical takeaway: your resting metabolism is by far the biggest slice of the pie. Even modest increases to your BMR add up over weeks and months because it’s running 24 hours a day. That’s why strategies targeting resting metabolism, like building muscle, matter more than most people realize.
Build More Muscle
Muscle tissue is significantly more metabolically active than fat. Each pound of muscle burns roughly 4.5 to 7 calories per day at rest, while fat tissue burns far less. Organs like the brain, liver, and heart are actually the biggest calorie consumers pound for pound, with metabolic rates 50 to 100 times greater than fat tissue. But unlike your organs, muscle mass is the one metabolically active tissue you can deliberately increase.
Adding five or ten pounds of muscle won’t single-handedly melt fat away. The direct calorie increase is modest, perhaps 30 to 70 extra calories burned per day for that amount of new muscle. But resistance training also elevates your metabolic rate in the hours after a workout, and over time, a more muscular body handles nutrients differently, partitioning more calories toward muscle repair and less toward fat storage. Strength training two to four times per week is the most reliable long-term strategy for raising your resting metabolism.
Move More Outside the Gym
The calories you burn from everyday, non-exercise movement, things like walking, fidgeting, standing, carrying groceries, and taking the stairs, are collectively called NEAT (non-exercise activity thermogenesis). This is the most underrated piece of the metabolism puzzle. Research from the Mayo Clinic found that NEAT can vary by up to 2,000 calories per day between two people of similar size. That’s a bigger range than most people burn in an entire workout.
The difference often comes down to occupation and daily habits. Someone who sits at a desk all day and drives everywhere might burn only a few hundred calories through NEAT, while a person who walks frequently, stands while working, and stays generally active can burn well over a thousand. Simple changes like walking after meals, pacing during phone calls, and choosing stairs over elevators can meaningfully increase your daily burn without requiring dedicated exercise time.
Eat More Protein
Your body uses energy to break down and absorb the food you eat, and not all nutrients cost the same amount to process. Protein has the highest thermic effect: digesting it increases your metabolic rate by 15 to 30 percent of the calories consumed. Carbohydrates raise it by 5 to 10 percent, and fats by just 0 to 3 percent.
This means if you eat 200 calories of protein, your body might spend 30 to 60 of those calories just processing it. The same 200 calories from fat would cost your body almost nothing to digest. Swapping some carbs or fats for protein at each meal won’t revolutionize your metabolism on its own, but it reliably increases your daily calorie burn by a small margin. Protein also helps preserve muscle mass, especially if you’re in a calorie deficit, which protects your resting metabolic rate from dropping.
Try Higher Intensity Exercise
All exercise burns calories, but higher intensity workouts create an afterburn effect. After vigorous exercise, your body continues consuming extra oxygen to recover, repair tissue, and restore its systems to baseline. This post-exercise calorie burn can last anywhere from 15 minutes to 48 hours depending on the intensity and duration of the workout. One study estimated the afterburn effect produces a 6 to 15 percent increase in overall calorie consumption from the session.
High-intensity interval training (HIIT), heavy resistance training, and sprint-based cardio all generate a more pronounced afterburn compared to steady-state walking or light jogging. You don’t need to do HIIT every day. Two or three sessions per week, combined with regular moderate activity, gives you the metabolic benefits without the injury risk that comes from overdoing intense training.
Don’t Slash Calories Too Low
One of the fastest ways to slow your metabolism is to eat too little. When you dramatically cut calories, your body adapts by reducing energy expenditure. Your resting metabolic rate drops, you move less without realizing it (NEAT decreases), and your body becomes more efficient at running on fewer calories. This is often called “metabolic adaptation,” and it’s one reason crash diets backfire.
A moderate calorie deficit of 300 to 500 calories per day is enough to lose fat without triggering a severe metabolic slowdown. Eating enough to support your activity level, prioritizing protein, and including regular resistance training all help signal to your body that it doesn’t need to conserve energy.
Sleep Enough
Poor sleep disrupts more than your energy levels. Sleep deprivation increases hunger and cravings, makes you less likely to exercise, and reduces the proportion of fat you lose during a calorie deficit. While earlier research suggested that sleep loss directly altered appetite hormones like ghrelin and leptin, a 2025 meta-analysis found the hormonal picture is less clear-cut than once thought. The practical effect, however, is consistent: people who sleep poorly tend to eat more and move less, both of which lower effective metabolic rate.
Aiming for seven to nine hours per night supports better body composition, more consistent energy for training, and healthier eating patterns. If you’re doing everything else right but sleeping five or six hours a night, that’s likely undermining your results.
What About Spicy Foods, Coffee, and Cold Water?
You’ll see these recommended everywhere, and they do have small, measurable effects. Capsaicin, the compound that makes chili peppers hot, stimulates a temporary increase in energy expenditure. But the effect is modest enough that it won’t offset a poor diet. Drinking ice-cold water (around 3°C) caused a small 4.5 percent bump in energy expenditure over 60 minutes in one study, while room-temperature water showed no thermogenic effect at all.
Caffeine does temporarily raise metabolic rate, and most regular coffee drinkers are already getting this benefit. These tools are fine to include, but they sit at the very bottom of the priority list. Building muscle, staying active throughout the day, eating enough protein, training with intensity, sleeping well, and avoiding extreme dieting will collectively do far more than any food or drink.
Your Metabolism and Age
Many people assume their metabolism crashes in their 30s or 40s, but a large-scale study published in 2021 found something different. After a rapid metabolic rate in infancy, metabolism slows by about 3 percent per year through childhood and adolescence, then levels off. Your metabolic rate stays remarkably stable through your 20s, 30s, 40s, and 50s. The real decline doesn’t begin until after age 60, and even then it’s gradual, only about 0.7 percent per year.
The metabolic slowdown most people feel in middle age is largely driven by losing muscle mass and becoming less active, not by some unavoidable biological clock. That’s good news, because both of those factors are within your control.