"The answer is: it depends on your metabolism," Dr. Arad told POPSUGAR. Your metabolism relates to how your body produces energy from fats, sugars, and proteins as well as how it stores energy. Your metabolic rate, the number of calories you burn in a unit of time, provides insight on whether you have a fast or slow metabolism and how much energy you burn. To determine your metabolic rate, you'll need to get a resting metabolic rate (RMR) test (typically $250, but rates will vary), which are currently offered at specialized clinics like Fitnescity.
Most people are familiar with calories but few know exactly what they are. Calories are units of measure assigned to foods to show how much energy it contains. Your body expends a certain number of calories as energy everyday. If you consume more calories than you expend, the excess will be stored as body fat. If you consume less than you expend everyday your body will have to use stored body fat to meet energy needs.
As chronic obstructive pulmonary disease (COPD) advances, about 35% of patients experience severe weight loss called pulmonary cachexia, including diminished muscle mass. Around 25% experience moderate to severe weight loss, and most others have some weight loss. Greater weight loss is associated with poorer prognosis. Theories about contributing factors include appetite loss related to reduced activity, additional energy required for breathing, and the difficulty of eating with dyspnea (labored breathing).
Tight deadlines, bills, your kids—whatever your source of stress, having too much of it may make it harder for you to drop unwanted pounds, especially from your middle. And it's not just because you tend to reach for high-fat, high-calorie fare when you're stressed, though that's part of it. It's also due to the stress hormone cortisol, which may increase the amount of fat your body clings to and enlarge your fat cells. Higher levels of cortisol have been linked to more visceral fat.
Once your body adapts to the stress you put on it, it's time to change the stress. Personally, I'd only run for a long distance if I were being chased by a hungry lion, so it's unlikely you'd catch me on the treadmill. I prefer to do weight training circuits combined with calisthenics, sprints, and jumps to keep things interesting. You can mix things however you wish, as long as you find it challenging.
Carbohydrates are extremely important to training since they are the primary fuel source for working muscles. During weight training the body uses ATP for energy. ATP is replenished through something called the glycolytic pathway. This pathway converts glucose into ATP. Glucose (carbohydrate) is obtained from the bloodstream or from carbs stored in the muscle tissue as glycogen.
Since only two HIIT sessions should be performed per week another type of cardio will be needed for the rest of the cardio sessions throughout the week. MISS (Moderate Intensity Steady State) cardio is the perfect type of cardio to fill in any remaining cardio that needs to be performed during the week. This will burn a great amount of calories while sacrificing very little muscle tissue and burning fat through different pathways from the HIIT.
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.