Most people know that doing cardio is beneficial and important for weight loss and health. Although there is a lot more to it that aimlessly running on treadmills or taking the dog for a walk. I hope to explain why doing cardio regularly is beneficial and how to do it in a way that maximises the potential benefits.
The human body is designed to be physically active. And when we are not, it is detrimental to our health. Sedentary people lose their cardiovascular fitness and tend to have poor health of the heart and lungs. Exercise that puts stress on the lower body such as walking and running, causes the bones of the legs to become stronger. This prevents osteoporosis. Running and walking is a great way to release stress and blow off steam. Morphine-like chemicals are released when you do cardio at a high intensity. It’s a natural high. Cardio also helps increase the length and quality of sleep. This helps improve energy levels. When you’ve got blood pumping through your veins and oxygen readily supplied to the muscles and brain you feel brighter, more alert and more productive. And of course, weight loss. Doing cardio burns calories.
Okay, so we know that it’s beneficial to do cardio. Now, what do we do, and for how long? ACSM recommends 3-5 days of cardio for about 30-60 minutes. I think it is important to do something daily like walking to work, or taking the dog for a walk. But it is more important to do some high intensity exercise. This is what improves heart health. Doing exercises at 70 to 85% of your maximum heart rate (220 minus your age) or at a “moderately hard” intensity is what I always advise. Start off doing 20 minutes or whatever you can do, and then gradually increase the time. I recommend doing this 2-3 times a week. However, sedentary beginners may want to begin at a lower level of intensity. I recommend the talk test. Exercise at an intensity that you can hold a conversation without being too breathless.
Now people ask me “but if I train at a lower level of intensity I’ll lose more fat right?” In a way. You use a higher proportion of fat to carbs when you train at low intensity. However the total amount of calories used is more at a higher intensity, carbs, fat or otherwise. Put simply, don’t worry about calories of fat, but the total calories lost. You lose more total calories at higher intensity.
There are many types of cardio exercise out there. My advice? Do something fun. Take a class that you like, go for a walk, play sport, bike to work. If you plan to jump on a treadmill or bike, that’s fine, just vary the resistance, do interval training. Interval training involves varying the intensity between periods of hard and easy levels. Try doing 2 minutes of an easy intensity exercise then 1 minute of hard intensity exercise. Repeat this until the total exercise time is over. Any ratio of different intensities is fine, just experiment with different interval times and lengths. Interval training is beneficial because you train at a high intensity (and get the heart benefits of training hard) but you can do it for a longer period of time than training continuously.