Fat-loss is probably the biggest reason people pick up fitness routines, but many are not doing what it takes to achieve it. There is a lot of conflicting information over what exercises are best to burn fat, and most people do not know where to start. Your exercise is indeed important to fat-loss, but you must tailor it to give you the maximum post-workout burn, or EPOC.
What is EPOC?
EPOC stands for excess post-exercise oxygen consumption. As the name would suggest, EPOC begins after your workout is over. Also referred to as the afterburn, this process is your body’s way of bringing itself back to normal after the rigors of a workout. It does this by:
- restoring ATP (adenosine triphosphate) that was generated and used for energy during the workout
- rebalancing hormones
- restoring the levels of oxygen in the blood and muscles
- restocking glycogen in the muscles
- repairing damaged tissues
Prior to your workout, your body is operating at its Basal Metabolic Rate (BMR), or metabolism, which is the rate at which your body burns calories at rest. Exercise increases BMR and the cells use oxygen to make energy (ATP) to power through the workout. Muscles are torn, fuel reserves are depleted, and the body has an oxygen deficit. In order to restore your body to homeostasis, or its resting state, EPOC must take place.
Since your metabolism is already increased and because fuel reserves are low, your body often burns fat stores during EPOC. Not only is calorie burning increased during your workout, but it continues through the duration of EPOC. What makes this better is that high-intensity and long-lasting workouts produce a longer EPOC, allowing for even more calorie burning. You can think of it almost like extra-credit, or a freebie to your workout. Essentially, you are burning bonus calories by simply exercising smarter.
How Long Does EPOC Last?
The duration of EPOC can vary from 15 minutes to 24 hours and sometimes shorter or longer depending on a variety of factors. The biggest of these factors is the intensity of the workout. In general, the higher intensity the workout, the larger oxygen deficit in your body. The more oxygen deprived your body is, the longer EPOC will last. Intensity levels will vary greatly from person to person depending on their athletic fitness.
Factors that can affect the length of EPOC include:
- Workout intensity
- Duration of the workout
- Frequency of workouts
- Overall fitness level.
Lower intensity workouts at longer durations can also prolong EPOC, but you might burn fewer calories than you would with a higher-intensity workout. Similarly, a person who is just starting with an exercise regimen will likely spend more time in EPOC than a seasoned athlete simply because they are not accustomed to exercise intensity. If you’re in better shape, you will need to work out harder to burn the same amount of calories, both during and after your workout.
How Does Your Metabolism Behave During EPOC?
Your metabolism remains high during EPOC because energy is required to return your body to its resting state. Therefore, you are still burning calories for the duration. The number of calories burned depends on the same factors that contribute to the length of EPOC.
This study determined that both cyclists and runners doing speed interval training burned approximately 20 calories per hour for up to 10 hours post workout. Some burned up to 65 calories within the first three hours.
Exercises that Maximize EPOC
This is where things often get confusing for those who want to focus on fat loss. We are told that in order to efficiently reduce fat, keeping your heart rate in fat-burning mode (instead of cardiovascular mode) is key. The CDC best explains target heart rates here. To keep your heart in fat-burning mode, exercise should only be moderate like slow jogging, brisk walking or something like ballroom dancing.
However, EPOC cannot happen if the body does not enter into oxygen debt. To do this, you must deplete your fuel stores which will fatigue your muscles. A moderate workout, one in which you can still hold a conversation, will generally not put you in EPOC. So, while this type of exercise will indeed burn calories, you will not reap any benefits from EPOC. To maximize EPOC, you must engage in higher-intensity workouts.
Similarly, athletes who exercise at roughly the same intensity levels during every workout are not going to benefit from extra caloric burn from EPOC as the duration will be shorter. This leads us to the exercises that do assist in maximizing EPOC. The following list goes over the best workouts for maximizing your afterburn.
Strength training encompasses any type of workout that uses resistance and is incredibly versatile. You can do exercises like push-ups, planks and squats that use your own body weight from the comfort of your own home. You can find affordable resistance bands or free weights to get your workout in. Gyms are also stocked with different weight machines to target various muscle groups.
Keep in mind that the larger and the more muscle groups you work out, the better the EPOC. Circuit training that focuses on alternating both upper and lower body exercise will burn significantly more calories than only working out certain areas (i.e. chest day).
Not only is strength and circuit training one of the best ways to maximize EPOC, but it also helps to strengthen bones, build muscle, control chronic condition and improve mental clarity and focus. Increasing your lean muscle mass with strength training will also aid in burning calories. To maintain each pound of muscle, the body burns five to seven calories a day.
HIIT, or high intensity interval training, workouts are one of the best ways to maximize your EPOC. Typically only lasting between 20-30 minutes, high-intensity workouts incorporate periods of moderate-intensity exercise with shorter periods of high-intensity exercise. Any type of aerobic exercise like running, cycling, stair climbing or elliptical machines are ideal for this type of workout.
HIIT workouts begin with a moderate warm up of two to five minutes followed by a high-intensity burst for 30 seconds to one minute. This pattern mixed with rest is then repeated for the duration of the workout. Depending on your personal ability, you can adjust the times for moderate and high-intensity circuits.
Running and Cycling
For both runners and cyclers, especially when training for races, workouts can become more evenly paced and steady. Though this is a great way to practice cardio conditioning and training muscles, it does not help to extend your EPOC. If burning calories is your goal, try to incorporate speed-interval training into every other workout.
Of course, a healthy diet and lifestyle play huge roles in weight-loss, but we cannot overlook the benefits of EPOC. While this afterburn will not burn as many calories as you will during your workout, the extra calories burned afterwards make it worth it. For those of us serious about toning up and losing fat, every calorie counts.
We hope these tips have encouraged you to focus on EPOC for your future workouts. The higher intensity and longer your workout the better the afterburn.