Yes, exercise burns calories and yes, exercise can build muscle mass. Since muscle burns three times more calories than fat, the more you exercise and the more muscle you make, the faster your metabolism.
But the need to exercise or at least get adequate physical activity, which is just less structured movement, it's far more fundamental.
Exercise balances many of our hormones and immune system regulators. It can reduce cortisol as well as the harmful inflammation caused by stress. In the past decade, researchers have discovered, that when muscles contract, they release chemical messengers called myokines.
These messengers travel throughout the body to affect how every part functions. Myokines influence our metabolism as well as our heart, muscle, fat, brain, liver and other organs. They are critical mechanism by which exercise prevents and treats over 40 medical conditions.
An example of a myokine is brain-derived neutrophic factor. Released during exercise, this factor acts on the brain to generate new brain cells and build new pathways among existing ones. It helps our mind function clearer and builds reserve against dementia. When it comes to fighting obesity, brain-derived neutrophic factor is a key influencer on the pathways that control our body weight and energy balance. Many other myokines help burn fat and clear blood sugar from circulation. You can think of myokines as the checks and balances to the harmful effects of excess fat.
Whereas belly fat releases chemicals and proteins that increase inflammation and hence the risk of many diseases such as diabetes, heart disease, and stroke, myokines released by contracting muscle, reduce inflammation and counteract this damage. Your muscles need to move a threshold amount, however, to switch on these health-promoting chemicals.
Different types of muscle, fast-twitch or slow-twitch, release different sets of myokines. Therefore, you need a mix of aerobic exercise such as walking, jogging, dancing, or biking as well as strength resistance exercise such as lifting weights, yoga, or body resistance, to get all the health and metabolic benefits of exercise. The recommended amount is 30 minutes a day of aerobic exercise, and twice a week of strength resistance exercise.
Independent of the need for physical activity, there's another culprit that commonly gets in the way of losing weight; being sedentary for an extended amount of time. Muscles uptake glucose and triglycerides out of our circulation. When we sit for more than an hour, muscles power down. They slow or stop this critical function. As a result, metabolism slows and blood sugar and triglycerides as well as body weight rise.
Simple changes like standing up or pacing for a minute every hour can reactivate muscles. In one study, among people who worked a sedentary job, researchers compared the group who took the least standing breaks to the group that took the most. They found that those who took frequent breaks had a lower blood sugar, cholesterol, body mass index, and an almost six centimeter smaller waist circumference. Getting up and moving as often and as much as you can, to get something, use the restroom or run errands has other benefits.
Over the course of the day, it is from these light activities rather than exercise that we burn the most calories. That's because even though exercise burns a lot more calories per minute, we typically only spend about 5 percent of our day exercising. On the other hand, we spend nearly a third of our day doing light activities. Cumulatively, the calories burned during these everyday activities adds up to more than that from exercise. Even if you don't like to exercise, moving more can make a significant difference in your weight and overall health.
Try to build more activity into your day. A few minutes walking in a parking lot, some more taking the stairs or walking around your block, until you reach 30 minutes a day. Try to stand out more often. During conference calls, by having walking meetings, walking over rather than emailing a colleague, or using a standing treadmill desk.