Scenario: Earl is 30 years old, 5 feet 3 inches tall, weighs 150 lbs, with 30% of that weight being fat. He is a type 2 diabetic but that has not stopped him. He is on a fitness journey and has made physical activity a key part of his lifestyle. As a person with type 2 diabetes, Earl is well aware that his body easily frees glucose from storage (glycogenolysis) but has difficulty transporting the glucose into muscle fibers. This causes elevated blood sugar. Earl enjoys swimming and uses swimming as exercise for endurance. When Earl swims, he is particularly concerned that once his glucose stores run low, his body will not successfully switch to fat oxidation.
Question: Calculate Earl's BMI. Now convert Earl's body fat into kilocalorie values.
a) How many pounds of fat does Earl have?
b) Assuming that the energy value of body fat is 3500 kcal per pound, how many kilocalories does Earl have stored in his body fat?
c) Suppose he loses 15 lbs. For the purpose of this question, assume that Earl exercised enough to retain virtually all his lean body tissue. Now he weighs 135 lbs. How many pounds of this is fat? What percentage of his body weight is now fat?
d) How many kilocalories does a 15-pound loss of fat represent?
e) If a periodized diet and exercise plan provides a deficit of 500 kcal/day (that is, 500 kcal less each day is eaten than is spent), how many days (or weeks or months) will it take to lose that much fat?
f) What are the best methods for assessing Earl's body composition, both in the field and in a laboratory? Would the recommended assessment method change from the beginning of Earl's journey to the end (assuming a large change in body composition)? Show all work.