You may be confused about exactly how hard to work during cardio. You may even think that high-intensity exercise is the only way to go. After all, you can burn more calories and, even better, you don't have to spend as much time doing it. But having some variety can help you stimulate all of your different energy systems, protect you from overuse injuries, and help you enjoy your workouts more. You can use a sample cardio workout schedule to set up a cardio program that includes a variety of different workouts at different intensities.
Stress may contribute to abdominal fat, according to several studies, including a recent one at the University of California, San Francisco. "When you're stressed, hormones like cortisol stimulate your appetite, slow your metabolism down and encourage fat storage inside your abdomen," explains Shawn Talbott, Ph.D., director of the Nutrition Clinic at the University of Utah. So what's a frazzled girl to do? "Find an activity that reduces stress for you, whether it's listening to soothing music or taking yoga, and do it daily," advises Talbott.
The upshot of all these chemicals floating around is big trouble for big-bellied guys. In a study at the University of Alabama at Birmingham, researchers took 137 men of all ages and sizes and used seven different measurements to determine their risks of cardiovascular disease. The single best sign of multiple heart-disease risks? No, it wasn't the guys' family histories or their cholesterol profiles. It was the amount of abdominal fat they carried.
A 2012 study also showed that people on a low-carb diet burned 300 more calories a day – while resting! According to one of the Harvard professors behind the study this advantage “would equal the number of calories typically burned in an hour of moderate-intensity physical activity”. Imagine that: an entire bonus hour of exercise every day, without actually exercising. A later, even larger and more carefully conducted study confirmed the effect, with different groups of people on low-carb diets burning an average of between 200 and almost 500 extra calories per day.
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.