After cardiovascular exercise or weight training, the body continues to need oxygen at a higher rate than before the exercise began. This sustained oxygen consumption is known as excess post exercise oxygen consumption (EPOC). More recently, researchers have used the term EPOC to describe the several different events that occur as the body restores itself to homeostasis, or rest.
This article will describe the physiological factors that contribute to EPOC, discuss its relation to weight management and review a recent article on EPOC and resistance training.
Body: During EPOC the body is restoring itself to its pre-exercise state, and thus is consuming oxygen at an elevated rate. This means that energy is also being expended at an elevated rate. The following occurs during EPOC:
1) Replenishment of Energy Resources: Replenishment occurs for the immediate source of energy, known as the phosphagen system, which is comprised of creatine phosphate and ATP (adenosine triphosphate). In addition, lactate, a molecule that is produced during more intense exercise, is being converted to pyruvate for fuel utilization. The body is also restoring the muscle glycogen (a stored form of glucose) that has been used during the exercise bout.
2) Re-oxygenation of Blood and Restoration of Circulatory Hormones: During exercise metabolism, large amounts of oxygen are used to break down food substrates for energy. Therefore, the body continues to expend energy after exercise to re-oxygenate the blood. In addition, in the post exercise period, the body restores the levels of circulatory hormones, which increased during exercise, to normal.
3) Decrease in Body Temperature: As energy is liberated from the exercising muscle tissues of the body, heat is produced. Thus, during EPOC, the body must expend energy to return to the normal core body temperature.
4) Return to Normal Ventilation and Heart Rate: Energy expenditure is greatly elevated as the body rapidly returns to a normal breathing rate. Heart rate is also returning to a pre-exercise rate.
Types of Exercise to achieve EPOC effect
You basically need to aim for a workout in the 85-90% of your heart rate max a couple of times a week and your goal will be accomplished. Activities such as sprinting and circuit/interval training do wonders in terms of EPOC Training. Do anything that will make your heart work hard to pump oxygen-rich blood through your body. Movements that recruit multiple large muscle groups initiate the EPOC effect after exercise; here are 3 exercises to try:
Sprinting: Sprinting provides another training method for initiating EPOC. Sprinting places high demands on the entire body to perform with increased emphasis on the quadriceps, hamstrings, core, and gluteal muscles. A sample sprint exercise involves running as fast as possible for 50-60 yards then resting for 30 seconds and repeating. For an even harder task attempt running up a set off stairs.
Deadlift: The deadlift incorporates many muscle groups like the quads, hamstrings, glutes, lower back, lats, rhomboids, trapezius and forearms. To execute the deadlift, stand behind a barbell with your feet hip-width apart. Bend the knees and grab the bar using a shoulder-width distance. Keep your shoulders back and chest up throughout the movement and lift the bar until you are standing straight. When performing quick and explosive movements ensure form is perfect to prevent injury.
By Phil Downing
Personal Trainer at Liverpool Personal Training Studios