By exercise mechanics I mean the basics of how your body works. If you like do it yourself projects this is a great post for you. If you wish you had a simple guide telling you how your body responds to exercise, and how you can change your workout habits to get the results you want, this is an excellent place to start.
Below I’ll go over the main types of exercise and what they are good for, including length of exercise and intensity. I’ll also talk about stretching, warm ups, and cool downs, as well as when to go all out and when to rest.
What is Exercise?
First of all, what exactly is exercise? From a really basic standpoint, exercise is repetition. Using your body again and again to improve it. Your body reacts to different types of exercise in different ways. Exercise mechanics, or the rules governing exercise are measured by Frequency, duration and intensity. There are other things like flexibility, breathing control, and mental focus that all play a role, but for now I’ll just stick with the main three. Changing either duration or intensity change how your body is stressed and how it reacts. Your reasons for exercising should guide how you work out.
Do you know someone who works out but can’t seem to slim down? Or do you struggle with burning fat or building muscle? Maybe you’ve been told you need more cardio but you’re not sure exactly how that works. Usually the answer is in doing the right workout.
Frequency means how often you work out. More often means more stress on your body. You can get stronger, faster with greater frequency. Remember though, your body needs to heal between workouts. Too much, too often leads to injury and slows down your progress.
Duration is how long you work out at any given time. This is important since cardio benefit doesn’t come till you’ve spent at least 10 minutes of sustained exercise. Also, fat burning doesn’t kick in immediately, but usually needs 30 minutes or more for your body to switch from burning carbs to mainly burning fat.
Intensity is how hard you’re exercising. There are a few reasons this is important. Exercise too hard and you won’t be able to last more than a few minutes. Fat burning also happens at lower intensity while carbs are relied on for higher intensities. High intensity exercise builds bulky, anaerobic muscle, while lower intensity builds aerobic muscle.
Making use of all of this:
Knowing all of this about exercise mechanics is great, but how do you apply these in your workout?
Once again it all comes back to what your goals are. For disease prevention benefits to kick in, get at least 150 minutes a week (2 hours and 30 minutes) of moderate-intensity aerobic activity.
For fat burning there are a couple things to consider. First, lower intensity exercise mainly burns fat. great, you say, I just walk for a while and the fat will come off right? Sort of. remember that fat is measured as calories. Calories are a way to measure energy. So, fat is stored energy and a leisurely walk doesn’t burn much energy. Most of what it burns will be fat, not carbohydrates, but it still won’t burn much. If you walk long enough each day you’ll use enough energy and so burn quite a bit of fat, but not everyone has time for a daily two hour walk.
For Cardio benefits (a stronger heart, lungs, better circulation, more oxygen to the body, more energy, better mood, stronger immune system, better ability to focus/think, less risk of heart disease and stroke, and more.) The recommendation is 30 minutes of moderate intensity exercise most days of the week. This can either be done in one amount or broken up into 20 minute intervals. Don’t do less than 20 minutes or you won’t get the full benefit for your heart.
What is the solution then?
If low intensity exercise burns a higher percentage of fat, while high intensity exercise burns more calories but a lower percentage of fat, what is the best intensity for fat loss? The answer is somewhere in the middle.
This is really good news if you want the cardio benefits of exercise as well, since often a good low level cardio workout is also a good place to burn fat as well. VO2 is the way workout intensity is measured and exercising at just 20% of total will put you in a great fat burning range. However, at 50% intensity, even though the percentage of fat burned is less, you still burn 33% more fat overall.
If you are in poor shape and have to start at a low level, walking or other low impact workouts may be just your pace. Just remember you have to increase the duration to see results.
Shapesense.com has a decent fat burning calculator which may help you calculate the intensity you should work out.
The way to determine a good pace for your moderate intensity workout is:
- Your breathing quickens, but you’re not out of breath.
- You develop a light sweat after about 10 minutes of activity.
- You can carry on a conversation, but you can’t sing.