Human Anatomy and Physiology - N. I. Fedyukovich 2003

Metabolism and Energy Exchange
Assignments

1. Calculation of Basal Metabolic Rate Using Tables

Procedure. Using special tables (see App. 2), you can determine the average statistical basal metabolic rate of an individual based on their height, age, and body weight. By comparing these average statistical data with the results obtained from instrumental measurements of working METABOLISM, you can calculate the Energy Expenditure required to perform a specific physical load. A stadiometer and scales are used to measure the height and weight of the subject. If the subject is weighed while clothed, the measured body weight must be reduced by 5 kg for men and 3 kg for women. The tables are used as follows. For example, if a 27-year-old female subject is 172 cm tall and weighs 65 kg, locate the figure 960 next to the subject's body weight in the tables for determining women's basal metabolic rate (Part A). In App. 2 (Part B), find the age (27 years) horizontally and the height (172 cm) vertically; at the intersection of the age and height columns, the number 678 is found. By adding the two numbers (960 + 678 = 1638), you obtain the average statistical value of the normal basal metabolic rate for a woman of a given age, height, and body weight, which is 1638 kcal.

2. Calculation of Basal Metabolic Rate Using Reed's Formula

Reed's formula makes it possible to calculate the percentage deviation of the basal metabolic rate from the norm. This formula is based on the correlation between Blood pressure, Heart rate, and the body's heat production.

Procedure. Determine the subject's heart rate using a stopwatch and measure blood pressure using Korotkoff's method 3 times at 2-minute intervals, maintaining the conditions necessary for calculating the basal metabolic rate. The percentage deviation (PD) of the basal metabolic rate from the norm is determined using Reed's formula:

PD = 0,75 (HR + PP∙0,74) - 72, where HR is heart rate; PP is pulse pressure (the difference between systolic and diastolic blood pressure values).

The numerical values of heart rate and blood pressure are determined as the arithmetic mean of three measurements.

Calculation example. Heart rate is 75 beats per minute, blood pressure is 120/80 mmHg. The PD is equal to 0,75 [75 + (120 — 80) ∙ 0,74] — 72 = 0,75 (75 + 40∙0,74) — 11 = 6,45. Thus, the subject's basal metabolic rate is increased by 6,45% and remains within the normal range. To simplify calculations using Reed's formula, a special nomogram is provided (see App. 3). Using the nomogram, by connecting The Heart rate and pulse pressure values with a straightedge, the magnitude of the basal metabolic rate deviation from the norm can be easily determined on the middle line.

Protocol preparation. Record the obtained indicators. Compare the subject's basal metabolic rate data obtained via instruments with the result found in the table. Compare the table-derived basal metabolic rate value with the values obtained during the experiment using Reed's formula.