HIIT pairs quick bouts of high-energy exercise, at over 75% of your heart rate maximum, with low-effort rest intervals at less than 60% of your heart rate. Steady stat. SSCE training incorporates a low intensity exercise ranging from 60 to 75% of heart rate maximum, for a maintainable extended period.
For years, continuous aerobic exercise (SSCE) has been the chosen and proven method for achieving cardiovascular and respiratory health concomitant to substantial fat loss. However, research shows that HIIT leads to similar and, in some cases, better improvements in less time for some physiological markers.
VO2max is considered the body’s upper limit for consuming, distributing and using oxygen for energy production. Commonly known as maximal aerobic capacity, VO2max is a good predictor of exercise performance. Improving cardiovascular function increases the body’s VO2max and reduces all causes of mortality (death). Recent research by Daussin et.al. in 2008 measured VO2max responses among men and women who participated in an 8-week HIIT program and a continuous cardiovascular training program. VO2max increases were 15 % higher in the HIIT program than they were in the continuous training program (9%).
Skeletal Muscle and Metabolic Adaptations.
An increase in the size and number of mitochondria (the “energy factory” of a cell) is becoming a hallmark adaptation with HIIT. During exercise, mitochondria use oxygen to manufacture high levels of ATP (adenosine triphosphate, the energy molecule of the cell) through the breakdown of carbohydrates and fat. As mitochondrial density increases, more energy becomes available to working muscles, producing greater force for a longer duration (allowing an athlete to run longer at a higher intensity, for example). An increase in mitochondrial oxidative enzymes leads to more effective fat and carbohydrate breakdown for fuel. More effective fat and carbohydrate breakdown for fuel may benefit patients with diabetes and cholesterol problems. Excess post-exercise oxygen consumption (EPOC) and weight loss.
After an exercise session, oxygen consumption (and thus caloric expenditure) remains elevated as the working muscle cells restore physiological and metabolic factors in the cell to pre-exercise levels. This translates into higher and longer calorie burning after exercise has stopped. Studies show that the EPOC effect exists after both SSCE and HIIT exercise. For exercise regimens of comparable duration and intensity, SSCE exercise may expend more calories during the exercise itself, but the difference is partly offset by the higher increase in caloric expenditure that occurs during the recovery phase after HITT exercise. However high-intensity interval training was found in one study to result in greater loss of subcutaneous fat, even though the subjects expended fewer than half as many calories during exercise.
In conclusion, HIIT training programs have shown to be of great benefit to people in achieving their results. At Optimum we use these principles in our programs for appropriate clients. If you want to talk about how HIIT programs can help you in your training, then book in with one of our staff, so we can work with you on designing a specific program for you.