Healthy body weight has been associated with a reduced risk for chronic diseases such as Type-2 diabetes, certain types of cancer, obesity and cardiovascular disease.
Energy balance is very important when it comes to losing weight. Weight gain happens when the energy consumed in diet (calories) exceeds the amount of energy expended. If the amount of energy expended exceeds the amount of energy consumed, the result is negative energy balance, or weight loss.
To maintain your current body weight, the amount of energy provided by your diet should fuel daily activities and exercise.
Energy expenditure is the result of three main components:
- Basal metabolism which refers to energy required to maintain body functions at rest
- Thermic effect of food (energy needed to digest food)
- Physical activity (anything other than basal metabolism)
The body’s resting metabolic rate is an important player in our ability to stay lean, and it is affected mostly by our body composition with muscle mass being advantage for calorie burning. It’s important to emphasize a positive change in body composition instead of just weight loss.
Approximately 60-70% of total daily expenditure refers to Basal Metabolic Rate and the Thermic Effect of Food contributes with 5-10% to total energy expenditure.
Physical activity like walking, playing sports, house cleaning and working out in the gym, can contribute between 20% and 30% to total daily expenditure. Intense exercise like high intensity interval training boosts metabolism up to 48 hours after completion. This is why short intense exercises have been proven as more effective than steady state training or cardio.
Another positive thing that will influence your resting metabolism rate is providing your body with a steady flow of nutrients (frequent meals, all macronutrients provided).
Number of calories required for basal metabolism in a day can be determined by multiplying 24 hours by body weight and factor 0.9 for women and 1.0 for men.
Maya has 65 kg and her estimated energy requirements for basal metabolism would be:
24 h x 65 kg x 0.9 kcal/kg = 1404 kcal
This means that Maya should consume at least 1404 kcal to provide nutrients and energy to keep body functioning at rest.
Once you have the caloric output of your basal metabolism, multiply that by one of the following factors that best suit your activity level. The result will be your daily calorie needs/expenditure.
- 1.20 for sedentary lifestyle (little or no exercise)
- 1.375 lightly active (light exercise or sports; 1-3 days per week)
- 1.55 moderately active (moderate exercise or sports; 3-5 days a week)
- 1.725 very active (hard exercise or sports; 6-7 days a week)
- 1.90 extra active (very hard exercise or sports + hard physical job)
So from our example, let’s say Maya visits gym 3 times a week for an hour of moderate exercise. We would multiply her 1404 kcal (resting metabolism) with 1.55 and it would result with 2176.2 calories.
Every pound of bodyweight contains 3500 calories. To loose one pound per week you should consume 500 calories less each day (7 x 500 = 3500).
Although, it is true that you will lose weight by creating a continuous calorie deficit, if those calories come from processed foods with little nutritional value, you will feel terrible and constantly crave food. This is the diet that most people turn to but also a reason why weight gain is rarely permanent.
Losing weight does not mean losing fat. Creating calorie deficit will help you lose pounds but those pounds will be both muscle and fat tissue.
The secret to fat loss and having a lean body is building some calorie burning muscles and creating a moderate calorie deficit at the same time.
Losing 0.5 – 1 pound per week is ideal. If you are very overweight, than a loss of 1.5 lb. per week is acceptable and if you need to get rid of just a few pounds then ideal would be 0.5 lbs. per week (250 calories deficit/day).
Maya’s goal is to lose 5 pounds before her wedding in 3 months and ideal weight loss for her is 0.5 lb per week. That means she will have to make a calorie deficit of 250 calories.
Her daily calorie needs are 2176.2 calories per day (we got this number from the calculation in the first example) and when you subtract 250 calories, you get 1926 calories per day in order to lose 5 pounds in 2 months
There are just few simple steps between you and weight loss:
- Eat 5 meals a day, 2-3 h apart that consist of whole foods, built around a lean protein source
- Eat 250-500 calories less than you burn daily to lose 0.5-1 lbs.
- Maximize your calorie expenditure by doing short high intensity, muscle building exercises.
Always have in mind, you can do anything you want in your life you just have to decide and start today!