In the US $51 billion dollars is spent annually on weight loss products. A Canadian survey revealed that approximately half of the adults in this country are overweight. There are so many gimmicks that promise to melt fat from the body but if those products worked we would have a much slimmer society of people.
When comparing diet weight loss and exercise weight loss, those who exercise tend to lose more visceral fat (in between the organs) than those using strictly a diet approach. This reinforces the importance of maintaining regular physical activity.
Visceral fat can lead to inflammation, insulin resistance, and other metabolic problems. There is evidence that it plays a role in aging. Upper-body obesity is the most significant risk factor for obstructive sleep apnea, asthma, and gastroesophageal reflux. Abdominal fat will all lead to poor sleep; poor sleep means you drag through your day. Being tired, the body craves quick energy food, so people tend to snack on high–calorie junk food. That extra junk food leads to more abdominal fat, which leads to…. you get the idea.
Fat cells (adipocytes) are formed three times in your life; in utero, at about two years old and again at puberty. At this time in your life, you don’t have much say as to how much and where you store your fat. Your genes dictate this. Look at your parents to see where they carry their fat. Overweight parents have a greater chance of having overweight children. You can blame your parents for the number of fat cells you have, but you must take responsibility for the amount of fat in the cells. However, in extreme cases, our bodies manufacture new cells to absorb excess fat, even in adulthood.
Lack of physical activity is the number one reason we carry extra fat on our bodies. People may “eat too much” but if they moved around more they could enjoy the foods they love, within reason and moderation, without putting on extra pounds. When you eat more than your body requires energy input exceeds energy output. This is called a positive energy balance. A positive energy balance means you will gain weight (in the form of fat on your body).
Physical activity accounts for approximately 25% of daily calories expended. It sounds simple to say that you should simply move around more, but it really isn’t much more difficult than that. Eating more than your body needs and lack of exercise stimulates fat cell formation.
It’s important to understand that you have a basic amount of calories that your body needs just to stay alive. This is called your basal metabolic rate, or BMR. Severe diets that restrict calories may not meet your BMR.
The calories you require just to stay alive are for breathing, digestion, absorption of food, hormone release, blood circulation, controlling body temperature, cell growth, and everything else your body need to do to keep you alive. It is described as being in a physically and psychologically undisturbed state. In other words, you aren’t doing anything other than being alive. BMR slows down with age.
BMR affects everyone differently. It is the number of calories burned and will affect whether you gain, lose, or maintain your weight. BMR accounts for approximately 60-75% of your daily expenditure of calories. However, as you age your BMR declines by about 1 – 2 % per year after the age of 20.
To calculate someone’s BMR you’ll need to know their gender, weight, and height. The calculation is slightly different for men than for women. The only thing it doesn’t take into consideration is body composition. Leaner bodies need more calories than less lean ones. If your client is very muscular, this calculation won’t be as accurate.
Women: BMR = 655 + (4.35 x weight in pounds) + (4.7 x height in inches) - (4.7 x age)
Men: BMR = 66 + (6.23 x weight in pounds) + (12.7 x height in inches) - (6.8 x age)
Example 1: Sally (female) is 58 years old and she weighs 147 pounds and is 5’8” tall
(68 inches as there are 12 inches to a foot).
655 + (4.35 x 147 pounds = 639.45) = 1294.45
4.7 x 68” height = 319.60
Add 1294.45 + 319.60 = 1614.05
4.7 x 58 years old = 272.60
Subtract 1614.05 - 272.60 = 1341.45
So, Sally needs approximately 1341 calories per day just to stay alive!
Example 2: George (male) is 42 years old and weighs 210 pounds. He is 6 feet tall (72 inches)
66 + (6.23 x 210 pounds = 1308.3) = 1374.30
12.7 x 72 inches = 914.40
Add 1374.30 + 914.40 = 2288.70
6.8 x 42 years old = 285.6
2288.70 – 285.60 = 2003.1 calories per day just to stay alive
Now you can take into consideration your energy expenditure. This calculation can be a simple way to find out approximately how many calories you need to get through the day.
Multiply BMR x Activity Factor
3 – 5 times per week for 20 – 30 minutes per day
3 – 5 times per week for 60 minutes per day
3 – 5 times per week for 60 – 90 minutes per day
To calculate this:
Body Weight x 10 x Activity Factor
Example: Sally weighs 147 pounds, she is moderately active.
147 x 10 = 1470 1470 x 1.4 = 2058
Sally needs approximately 2058 calories to maintain her body weight.
Example: George weighs 210 pounds and is very active.
210 x 10 = 2100 1470 x 1.7 = 2499
George needs approximately 2499 calories per day to maintain his body weight
You won’t be making diet plans for people, but this might help them understand why they aren’t losing or gaining weight.
The more muscle you have the more fat you burn since muscle cells are more metabolically active than fat cells. People who cut calories and don’t exercise lose muscle tissue (sarcopenia), lowering their metabolism. So, some sort of resistance training is imperative if you are trying to burn fat.
Dietary fat has more than two times the calories than carbohydrates and protein. Eating fast, emotional eating and skipping meals may also cause obesity. People who skip breakfast have a 5% slower metabolism than those that do.
It is important to distinguish between fat loss and weight loss. After severe dieting, the body often returns to its "normal" weight but consists of more fat tissue and less lean.
The four factors associated with fat burning are intensity, duration, fitness level, and exercise type.
When an exercise is aerobic, more oxygen is available to the working muscle and the body turns to fat as fuel. Your body burns primarily fat in long, mild-to-moderate aerobic workouts (50% aerobic capacity). At this low-intensity fat is burned quite slowly; approximately 3-5 Calories per minutes. Higher intensity aerobic exercise has a greater total caloric expenditure, but a smaller percentage comes from fat. At a slightly higher intensity (70 – 75% of heart rate maximum) more fat is burned overall because more muscle is used, requiring more energy. The focus should be on maintaining the activity at the highest comfortable intensity.
During aerobic energy production, exercise can be maintained over a longer period of time with less fatigue. Aerobic exercise trains the body to burn fat and spare carbohydrates. To burn more fat as fuel exercise at a steady pace for a longer timer
Aerobically fit people burn more fat than those who are not fit. Fit people break down more fat following training due to several factors; increased efficiency of the heart, lungs, and muscles. Individuals who strength train burn more fat because more muscle means a higher metabolism.
Different types of exercises burn fat at different rates. Generally, the more muscles you use, the more fat you burn. Cross-country skiing for example, spreads the workload throughout the whole body, working no single muscle very hard. Moderate work using most muscle groups results in a higher rate of fat burning with less fatigue. Low-intensity exercise tends to be safe and more enjoyable for most people.
The more energy the whole system must expend and the more muscles involved in expending the energy, the shorter the time required to burn an equivalent amount of fat: The body expends the same amount of energy by:
- 40 minutes of walking
- 20 minutes of cycling
- 15 minutes of jogging
- 12 minutes of cross-country skiing
The most efficient way to expend fat-burning energy is to use a lot of muscles at a level that you can maintain for a longer period of time.
Here we looked at Fat Burning and aerobic exercise. In the next blog, we’ll look at how high intensity interval training (HIIT) can help you burn a lot of fat!