It is January, and many people make resolutions or set goals about what they want to achieve in the new year. Many people include a goal to lose weight, and when people think of losing weight, many of them think of jogging or 'hitting the gym.' Let us examine if this is really a good strategy for achieving weight loss.
Before we go on, I would like to say that exercise is indeed a good thing. Exercise helps your heart and lungs be healthy. The correct type of exercise strengthens your muscles and helps bone density. Exercise helps manage blood pressure. Exercise helps relieve stress and supports mental health, among other benefits.
Therefore, exercise is good and should be pursued regularly by everyone. However, in this article, we will examine using exercise specifically as one's main weight loss strategy. We will talk about calories.
For purposes of this discussion, a calorie can simply be defined as a unit of energy that is obtained from food. If you eat food with more calories than your body needs for daily functions, the extra calories get stored as fat mostly, and you gain weight. If you eat fewer calories than you need, your body uses previously-stored calories for energy, and you lose weight.
This is a simplified explanation, but it will do for our purposes. Now, let us do some calculations. Let us assume that you weigh 80 kg, and you want to lose 10 kg. It is said that a pound of fat is about 3,500 calories. A kilogram is, therefore, 3,500 x 2.2, which is 7,700 calories. Therefore, to lose 10 kg, the calories to be used up (or 'burned') through exercise is 7,700 x 10, which is 77,000 calories.
If you decide to start jogging to lose this weight, how many calories would you burn through jogging daily? I used an online calorie calculator to find out. If you jog for an hour and cover 8 km, you will burn about 697 calories in that hour. To burn a total of 77,000 calories, you will need to jog an hour each day for (77,000 / 697 =) about 110 days, while still controlling your eating to ensure that you do not consume extra calories, because then you would regain some of what you have jogged off.
If you jog this way three times a week, it will take you about nine months to lose 10 kg. In all this, we have not accounted for the time it will take for you to be able to build endurance to allow you to jog for 8 km in an hour, nor have we accounted for your body adapting to the jogging and therefore using fewer calories for each run. This is, therefore, an optimistic calculation.
So we can see three things from the above: First, by one losing 10 kg in 9 months, we see that exercise is a rather slow way to attempt to lose weight. Second, even while exercising, you still need to control your food intake, or you will lose weight at a slower rate, or even gain weight.
Third, to lose 10 kg in 9 months through exercise, you will need a rather high level of discipline, to both consistently maintain the exercise habit - three times a week for an hour each time - for nine months, while still controlling your eating for the entire period.
However, do not despair; if you want to lose weight, proper eating habits can yield satisfactory results faster and in a realistic manner. People lose even one kilo (or more) per week through controlling the calories they take in, rather than consuming them, then trying to burn them off.
This is why you may have heard it said that you could not out-train a bad diet, or you cannot outrun your fork.