What Is Your Fat-Burning Zone?

To effectively burn body fat, your heart rate should be in the "fat-burning zone," typically around 60-70% of your maximum heart rate (MHR). This zone is optimal because it allows your body to utilize a higher proportion of energy from fat rather than carbohydrates. It is generally associated with moderate-intensity activities such as brisk walking, light jogging, or cycling at a steady pace.

To find out your exact heart rate zones, schedule a VO2 Max test. To estimate your maximum heart rate, use the formula: 220 minus your age. For example, if you are 30 years old, your estimated MHR would be 190 beats per minute (bpm). The fat-burning zone would be 60-70% of 190, which is approximately 114-133 bpm. Exercising within this range encourages the body to use fat as the primary energy source, rather than relying on quick carbohydrate stores.

While exercising in the fat-burning zone does use a higher percentage of fat for energy, the total number of calories burned is also important. Higher-intensity exercise, such as interval training, burns more calories overall, including both fat and carbohydrates. After high-intensity workouts, the body also experiences an "afterburn effect," known as excess post-exercise oxygen consumption (EPOC), which increases the total amount of fat burned after the workout is over.

A balanced approach is best for long-term fat loss. Incorporating both moderate-intensity exercise in the fat-burning zone and high-intensity workouts allows for a combination of efficient fat utilization and an overall greater calorie burn. Resistance training should also be included, as it helps build lean muscle mass, which increases your resting metabolic rate, allowing you to burn more calories throughout the day.

Ultimately, heart rate is a useful tool to guide your training intensity, but a well-rounded exercise routine combined with a healthy, calorie-conscious diet is key to sustainable fat loss.