Have you ever wondered why high intensity interval training, aka HIIT, is so popular?
HIIT requires greater usage of lipids as a fuel source. Simply put, HIIT burns more fat!
Lactic acid is produced during and following an intense workout interval. This happens because blood flow cannot keep up with the oxygen transport needs for the working muscles to meet the demands of the movement and resistance during this anaerobic state. Huge amounts of lactic acid is built up during HIIT and this helps to remove excess fat through the requirement of increased fat and carbohydrate oxidation. “Some fitness experts argue that training at lactic acid threshold is necessary to burn fat.”¹
HIIT programs such as the HOTWORX workout, Hot Cycle, is perfect for intense intervals due to large muscle groups in the lower body that are used during the session.
HIIT produces increased EPOC
EPOC stands for Excess Post-Exercise Oxygen Consumption. Numerous studies have shown that HIIT results in a higher level of EPOC, which in turn requires a higher calorie after-burn. After-burn refers to the period of time directly following a workout when calories are burned at a higher rate than pre-workout levels as the body attempts to cool down to homeostasis which is the normal resting level of metabolism.
Steady state cardio versus HIIT
Steady state cardio workouts involve a constant rate of performance output usually at a more moderate heart rate level. For example, one might set a treadmill to a certain level of pace at a set level of incline to practice a steady state cardio workout. This is less effective for burning fat when compared to HIIT.
HIIT “significantly lowers insulin resistance and results in a number of skeletal muscle adaptations that result in enhanced skeletal muscle fat oxidation and improved glucose tolerance.”²
HIIT “results in significant increases in aerobic and anaerobic fitness, increased skeletal muscle capacity for fatty acid oxidation and glycolytic enzyme content, and increased insulin sensitivity.”³
In a US National Library of Medicine report, “Impact of exercise intensity on body fatness and skeletal muscle metabolism”, the results of a training comparison study were noted. Eight men and nine women participated in the study to determine the effectiveness of endurance training versus high intensity interval training. The endurance program ran for 20 weeks and the HIIT program ran for 15 weeks. Even with a reduced program time requirement, the HIIT sessions proved to be more effective for fat loss by a factor of nine! The HIIT program produced a much greater reduction in subcutaneous adiposity.
The results of that study provides even more support of the belief that HIIT burns more fat.
Taken directly from the Library of Medicine report, “the metabolic adaptations taking place in the skeletal muscle in response to the HIIT program appear to favor the process of lipid oxidation.”4
Now imagine what HIIT can do when combined with an infrared energy and heat environment during the workout. All of the benefits of HIIT mentioned in this article are amplified to a higher level with infrared. With infrared there is a higher calorie burn during the workout and, therefore, an even higher level of EPOC and fat burn than that of HIIT alone.
Now, go out and earn the fat burn with HIIT and infrared!
¹ https://www.sportsrec.com/425381-does-lactic-acid-burn-fat.html² https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2991639/³ https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2991639/4 https://www.ncbi.nlm.nih.gov/pubmed/8028502
