Since I wrote so much in the last post, I’m going to try to speed through this next set of issues. I will cover a lot more of metabolism in other posts. But here’s what’s important about your metabolism while sitting. I hinted in the post about metabolism that active tissue burns calories for you. Muscle is the most active tissue you have, and requires a lot of energy to maintain, burning most of your daily calories. When you don’t use your muscles frequently, a lot of things happen. The first thing that happens is your muscles are not as good at absorbing available fuels. The more active you are, the more energy-making mitochondria (your cell powerhouse) you have in your cells. When you do not have a large energy demand in your muscles, your muscles get rid of a lot of those mitochondria. If you don’t have a lot of mitochondria, your cells don’t have a lot of energy to do anything. In comes general fatigue, Metabolic Dysfunction #1. You’ll notice that it’s really hard to start getting into an exercise routine, but you feel like you have a lot more energy just a week in. That’s your body getting better at making energy for your cells. The other thing that happens when your body doesn’t really need a lot of energy to operate (like when you’re sitting), is your cells just don’t want to absorb any more fuel. When you have too much sugar or fat sitting around in your blood stream with nothing for it to do, it starts causing damage to the neighboring cells, including insulin resistance in muscles, also known as Type 2 Diabetes, and neuropathy in nerves. Metabolic Dysfunction #2 and #3. When your muscles aren’t needed for much and can’t absorb the fuels that they need, they too start to break down and go away. This decrease in lean body mass results in a slower metabolism, resulting in weight gain (from fuel storage), weight loss (from muscle loss), general fatigue, and other metabolic disorders. You need your lean body mass! Working muscle also helps challenge your bone strength. When your bones are not being challenged, they too start to break down, leading to osteopenia and osteoporosis. Metabolic Dysfunction #4, #5, and #6. The last thing I want to cover under metabolism is breathing, and respiration. Your respiratory system, just like your circulatory system, is a series of pipes that stretch and expand to increase oxygen flow. When you sit all day and your respiratory system does not practice expanding and exchanging oxygen, it keeps the pipes small, reducing air flow, reducing oxygen exchange, resulting in asthma, general fatigue, and other breathing problems. Those are Metabolic Dysfunctions #7 and #8.
How to stand up: Move more, burn more. It’s a simple concept, but so hard to put into practice. Exercise has numerous metabolic benefits, from fuel utilization, to body composition. When you get up more, you wake your body up, and start getting energy processes moving. The more you move, the more your body wants to be prepared for the next time you move, so it builds muscle, it makes more mitochondria, it stores more energy in the cells that need it (instead of the cells that don’t). More muscle and more active tissue means lots of good things for you body. When you exercise, your muscle cells activate what are known as GLUT-4 transporters, which help draw sugar out of the blood stream and into the muscles. Less sugar in the blood stream means less damage to your organs, and a decrease in your chance of diabetes. More sugar in the muscles means more available energy. As you start working on building muscle, your bones start to feel more force applied to them. While it is a slow process, prolonged pressure on your bones increases bone density, decreasing your risks for serious injury, especially as you get older. The important part? While bone density can increase through exercise for older adults, the process is very slow. The stronger you make your bones when you are young, the less bone density loss you experience as you get older. Finally, exercise helps you breathe better. It opens up your lungs, increases your breathing capacity, and increases your body’s ability to exchange oxygen to fuel your cells. Keep moving!