Page 42 - 86 human physiology part-2

Nutrition

To maintain a stable body weight, our consumption of calories needs to be equal to the amount of
calories we use in a day. You can determine your daily energy needs by determining your basal
metabolic rate (BMR). Your BMR is the energy your body needs to perform essential activities. Some
examples of essential activities are breathing, and maintaining organ function. Your metabolic rate can
be influenced by your age, gender, muscular activity, body surface area and enviromental tempature.

Physical Activity: An efficient way to use calories

Although the BMR stays about the same, we can dramatically change the amount of calories we
burn in a day by participating in physical activity. It is important to note that heavier people do more
work per hour than normal-weight people, for the same level of activity. We must spend about 3,500
Calories to lose one pound of fat. The best approach to weight loss, recommended by nutritionists, is to
reduce the Caloric intake by a small amount each day while gradually increasing your amount of
physical activity.

BMR: Determining how many calories we need

There are several factors that influence the BMR. Each person's body has different needs. BMR
needs vary with gender and body composition. Muscle tissue consumes more energy than fat tissue.
Typically, males need more calories than females, because they generally have more muscle tissue.
Males use up calories faster than women. BMR also varies with your age as well. As we age, our body
needs less and less calories. In addition, some health conditions can contribute to our needed calories.
Health conditions such as fever, infections, and hyperthyroidism are examples of health conditions that
lower your BMR. Our stress level effects our needed calorie intake as well. So does our increase or
decrease in consumption, and our rate of metabolism, which varies with individual genetics.

Calculating Your BMR

Here are the steps to determining your BMR, or, the amount of energy your body needs to perform
essential activities:

1. First calculate your weight into kilograms. This is obtained by dividing the number of
pounds by 2.2.
2. For Males: multiply your weight in kilograms by 1.0. For Females: multiply your weight in
kilograms by 0.9.
3. This number approximates the number of Calories you consumer per hour. Now multiply
this number by 24 to estimate how many Calories you need per day to support basic metabolic
functions.
4. The end result is your personal basal metabolic rate!

Glossary

Amino acids
The building blocks of protein in the body. There are nine essential amino acids that are not
manufactured by the body and must come from the diet.

Anabolism
Refers the cumulative metabolic intracellular, molecular processes by which every cell repairs

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