Regular physical exercise is essential to both physical and mental health. It helps to strengthen the heart and lungs, increases your energy levels, helps your sleep and mental health, and keeps your bones and muscles strong. "Move it or lose it" applies both to humans and all animals. The more we're able to move freely, the better we feel.
But can regular exercise alone help with weight loss? Sadly, no. You can't exercise your way out of a bad diet, and to rely chiefly on an exercise routine will not help you lose weight. There have been studies that exercise helps some when combined with dietary restrictions, and any time you move your body strenuously you are burning up calories that otherwise could have gone to your fat cells.
The human body's regulatory system is much more complex than food in and exercise out. All the time that you are awake, you are burning some calories, even when not exercising. You have a base metabolic rate (BMR) that is the ultimate decider as to how many calories you burn. If you're sedentary for 15 hours and exercise for 1, that all gets evened out by the BMR. Even for the most religious athletes, exercise accounts for only 10 to 30% of calories burned during the day.
The problem with exercise and weight maintenance is that the body has compensatory behaviors that sabotage the effects of the extra weight loss. Studies have shown that people who exercise tend to eat more than those who don't. For some, it's a conscious behavior to "reward" themselves for hard work, and for others it's an unconscious feeling of hunger that increases portions or frequency of eating.
The body can also go into a type of survival mode and slow down after exercise is over. The metabolic rate can drop if the body starts to conserve energy, if it feels it may need more in the future. This flies right in the face of the trainers who tell us the opposite, that regular exercise can speed up our metabolism. But it makes sense, because in nature after a long run away from a cheetah, a mammal would want to find a safe spot and rebuild their energy stores while resting to be ready for the next danger.
There are two basic types of exercise- aerobic and resistance. Aerobic exercise includes all of the popular ones- running, swimming, cycling, most sports, and walking. These are great for your heart and mental health, and should be a part of every day. I've seen recommendations from 30-60 minutes per day, and the average American is said to clock in at around 15 minutes per day, or about 2 hours per week.
Resistance exercises, like weight lifting and push-ups, are meant to build up muscle mass and increase strength. For those who don't care about how muscular they look, these exercises are rarely deemed important. That changes for senior citizens, who regularly begin to lose muscle mass in their 70's and 80's. For them, resistance exercises are important if they want to retain strength and mobility. Plus muscle mass burns more calories than fat, which is why seniors can get fatter as they age as well as becoming weaker.
So if exercise is not the path to weight loss, why do we rely on it so heavily? Part of the reason is that changing dietary habits is so hard, and adding exercise can be easier. It obviously does help some, especially with weight maintenance. But the main reason is that the food industry has been trying hard to absolve itself of the growing obesity epidemic, and pointing to exercise alone as the answer. Soda, beer, fast food and junk food companies have been filling the airways, billboards, and internet with picture of young, healthy and thin models eating their stuff. They sponsor fitness events and get athletes to do endorsements.
What the food giants don't tell you is that they are also working hard to combat public health initiatives that would truly fight obesity. Big food is against soda taxes, school lunch restrictions, food stamp guidelines, and labeling laws that would bring unhealthy eating habits out in the open and do some good. Instead, they push exercise, and blame lazy Americans for the growing obesity epidemic, leaving themselves and their sugar and fat laden offerings out of the equation.
So how much should we exercise? 30-60 hours a day sounds about right, even if it's just walking. The more you can push your body, the better physical shape you'll be in. People sometimes take better care of their dogs and cars than they do themselves. Take care of yourself first through both exercise and diet- you deserve it.
Weight loss tip #18. Exercise 4 hours a week or more, but don't count on it to make you skinnier. Do it for yourself and your family. Your brain and your body will thank you.
This article flies in the face of what many of us believe. It surprised me, as I've relied on exercise and still managed to get obese. Here are two articles that go into more depth.