There are those that claim HIIT is less effective than low intensity longer duration cardio. Their reasoning is that most of the calories burned during HIIT come from stored muscle glycogen (carbs) rather than coming from stored adipose tissue. This is true but this is not a bad thing. Research has absolutely proven that it does not make any difference whether stored carbohydrates or stored fats are used as the fuel source. The only thing that matters is how many total calories are burned and more total calories are expended through HIIT as opposed to low intensity low duration cardio.
1. Boost your metabolism throughout the day: Your BMR regulates how many calories you burn at rest and the more you move, the higher your BMR, and the more you’ll burn when standing still. Small efforts like taking the stairs, walking to pick up lunch, even playing pool with the guys during happy hour can all jumpstart your metabolism. (Check out these 30 Easy Ways to Burn Fat in 30 Minutes Without the Gym.)
High blood sugar levels coupled with high blood ketones, on the other hand, will mean that you have a pathologically low level of insulin – something non-diabetics do not suffer from. This can lead to ketoacidosis – a potentially life-threatening condition. If this happens, you’ll need to inject more insulin; if you’re at all unsure of what to do, contact a medical professional. Coveting really high blood ketones for weight control is not worth the risk for type 1 diabetics.
Muscle tissue is a biologically active tissue, this means that it needs and uses calories just to continue being. Some studies have shown that 1 pound of muscle can burn up to 50 calories per day by simply existing. This means that if you gain 10 lbs of muscle you can eat 500 more calories per day and still lose fat. This is just one of many reasons why it is so important to preserve muscle tissue while cutting fat.
According to a small study published in the journal Annals of Internal Medicine, people who slept for 8.5 hours a night for two weeks lost nearly twice as much weight on average than participants who slept 5.5 hours per night, despite the fact that they followed the same diet and workout plan. That's because when you get a good night's sleep, your hunger hormones, like ghrelin and leptin, stay in check. That means you're not going to wake up with a sudden hankering for a bacon, egg, and cheese. (Start working towards your goals with Women's Health's Body Clock Diet.)
At its core, burning fat comes down to the process of lipolysis—the breaking down of fat lipids, explains Seedman. This happens in the mitochondria of the muscles, or the powerhouses of the cells, responsible for generating the energy our cells need to do their jobs. Exercise has been shown to improve mitochondria function, which then promotes fat breakdown, Seedman adds. Plus, working out helps regulate pretty much all the hormones that optimize fat loss.