An average adult human requires 2,200 kcal of energy per day. Suppose your diet provides an average of 2,300 kcal per day. How many hours per week would you have to walk to burn off the extra calories? Swim? Run? (See Figure 6.4.)

Verified step by step guidance

1. Step 1: Calculate the extra calories consumed per day by subtracting the required calories from the provided calories: 2,300 kcal - 2,200 kcal.
2. Step 2: Multiply the extra calories per day by 7 to find the total extra calories consumed per week.
3. Step 3: Refer to Figure 6.4 to find the number of calories burned per hour for walking, swimming, and running.
4. Step 4: Divide the total extra calories per week by the number of calories burned per hour for each activity to find the hours needed per week for walking, swimming, and running.
5. Step 5: Summarize the hours per week required for each activity to burn off the extra calories.

Key Concepts

Caloric Balance

Caloric balance refers to the relationship between calories consumed through diet and calories expended through physical activity and metabolism. To maintain weight, the number of calories consumed should equal the number of calories burned. In this scenario, the individual consumes 2,300 kcal daily, which exceeds the average requirement of 2,200 kcal, creating a surplus that needs to be addressed through physical activity.

Metabolic Equivalent of Task (MET)

MET is a unit that estimates the amount of energy expended during physical activities compared to resting. One MET is defined as the energy cost of sitting quietly, approximately 1 kcal/kg/hour. Activities like walking, swimming, and running have different MET values, which help determine how many calories are burned per hour based on the intensity of the activity and the individual's weight.

Energy Expenditure from Exercise

Energy expenditure from exercise quantifies the calories burned during physical activities. The figure provided illustrates the kcal burned per hour for various activities performed by a 67.5-kg person. By knowing the kcal burned for activities like walking, swimming, and running, one can calculate how many hours of each activity are needed to burn off the excess calories consumed, thus achieving a caloric deficit.