II. Long-Distance Runners vs. Sprinters
III. Definition of High-Intensity
IV. Impact on Body Fat
V. Potential Mechanism
Key words: cardio, fat loss, HIIT, weight training, high intensity interval, ab workouts, ab exercises, abs, workout for abs, get abs, sprinting
First of all, get your mind out of the gutter! You need to focus. Why?? It’s because you may be one of the many people searching for a new way to shed some fat. Those remaining pounds just refuse to come off, even after all of those hours on the treadmill…but what other option is there?? Let me present an example that we’ve all seen...
II. LONG-DISTANCE RUNNERS VS. SPRINTERS
But first, let’s define some terms. An individual’s aerobic capacity is the maximum amount of oxygen that the body can remove from circulating blood for use in exercising muscles. It can be measured using a VO2 max test, which determines an individual’s aerobic capacity (VO2 max). This value is used in research to define the intensity of an exercise. For research purposes, a high-intensity exercise is one in which aerobic capacity is 85-250% VO2 max. But generally, your VO2 max value directly correlates to your level of cardiovascular fitness.
IV. IMPACT ON BODY FAT
A variety of studies have been conducted describing the benefits of HIIT in sports training. But for this forum, I will concentrate on one study that identified greater weight loss benefits than low-intensity training.
V. POTENTIAL MECHANISM
So what exactly is the mechanism behind this? From what I’ve read, I was unable to identify anything definitive. However, there is one theory that could be a potential mechanism. Studies have shown that a potential method for increasing fat oxidation is to maintain glycogen stores at a low range (Flatt, 1987). It is also well known that as the intensity of an exercise increases, glycogen (carb) metabolism increases and fat metabolism decreases (Holloszy et al., 1998; Romijn et al., 1993). In other words:
(Schrauwen et al., 1998; Schrauwen et al., 1997), but their findings did not completely confirm this theory. Briefly, these studies investigated the amount of fat oxidation following high-intensity exercise. However, there was no comparison of high-intensity fat oxidation to low-intensity fat oxidation. That comparison is essential to properly validate this theory. Nonetheless, I believe the marathon runner/sprinter comparison along with the Tremblay et al. research is enough evidence to give HIIT a try!
VI. HIIT METHODS
So here are some recommendations for ways to try HIIT:
2. Run sprints on a field, basketball court, or hill with 15-30 second rest periods.
3. Take classes like spinning or bodypump. These can be a fun (and sometimes easier) way to take part in some high-intensity exercise.
4. Using a treadmill, place your feet on either edge and set the speed at a fast pace that you feel comfortable with to run sprints (6-10 mph, adjust depending on your comfort level). You can also increase the incline to 4-8% and make it more challenging if you feel comfortable with it (5-8% incline). Sprint for 15-20 seconds, then hop up, with your feet landing on either side of the moving treadmill. Rest for 20 seconds, then hop back on the treadmill for the next sprint. After 10-15 minutes, you’ll feel this.
5. Use the interval settings on a stationary bike.
A couple of other comments:
1. In no way am I saying that you should never do low-intensity cardio exercises. I'm simply suggesting a different type of exercise for those who are looking for new things to try.
2. I wouldn't do HIIT before, on, or the day after a leg weight-training day. Your legs will need time to recover from both HIIT and your leg day, and doing them too close together will not provide necessary recover time.
Go HIIT It!!