THE BENEFITS OF HIIT TRAINING
WHAT IS HIIT?
High Intensity Interval Training (HIIT) is a form of exercise that utilises short periods of anaerobic exercise with less intense periods of work or recovery. It’s a type of cardiovascular exercise and a typical HIIT session can last anywhere from 4 – 30 minutes. These short, intense workouts can improve athletic capacity and conditioning as well as improving glucose metabolism.
HIIT sessions generally consist of a warm-up, followed by several repetitions of high intensity exercise separated by periods of medium or low intensity exercise or rest. In order to be most effective, the intense periods should be performed at near maximum effort.
Due to HIIT sessions usually lasting no more than 30 minutes, they are an excellent way to maximise a workout within a limited time period. Using a clock or timer is essential to keep track of rounds and intensity.
WHAT ARE THE BENEFITS OF HIIT:
Aside from increasing fitness and raising the threshold at which the body can operate aerobically, one of the primary benefits of HIIT relates to ‘excess post exercise oxygen consumption’ or ‘EPOC’ (informally called after-burn). This term is used to describe the increase in oxygen intake following strenuous activity in order to erase the body’s ‘oxygen deficit’. EPOC is the process by which the body is returned to a resting state and adapts to the exercise that it just performed, including hormone balancing, replenishment of muscular fuel stores and cellular repair. This oxygen consumption replenishes the phosphagen system, which helps return creatine and ATP to resting levels. It also helps to oxidise lactic acid produced during intense bouts of exercise, and fuels the body’s increased metabolism from the increase in body temperature caused by exercise. EPOC is accompanied by elevated fuel consumption – meaning fat stores are broken down. In simple terms, this after burn effect means that the body keeps on working once the workout is over, burning calories and breaking down fat stores as you go about your day.
The duration and intensity of the after-burn effect is directly related to how intense the workout has been. This also occurs with medium to low intensity exercise, and isn’t exclusive to HIIT. However, the most significant effect comes from intense exercise, with various studies showing that excess oxygen consumption could still be taking place over 24 hours later depending on the intensity of the workout. It’s widely agreed that the effects reach their peak 1 hour after a workout and decrease from there on, with the after-burn effect equaling approximately 5-20% of the energy consumed during training.