Lecture 20 - Metabolism and Exercise

Metabolism

The sum of the chemical reactions in the body that maintains life

Basal Metabolic Rate (BMR)

The minimum energy expenditure needed to sustain life. BMR involves essential functions like heart pumping, breathing, digesting, and maintaining homeostasis

Resting Metabolic Rate (RMR)

The energy expenditure whenever an individual is available. RMR involves activities like walking, sweating/shivering, and eating

Total Energy Expenditure (TEE)

The total energy the body uses, which includes RMR, Physical Activity, and the Thermic Effect of Food (TEF)

Caloric Intake

The energy entering the body (what you eat), consisting of Carbs, Protein, and Fat

Thermic Effect of Food (TEF)

The amount of energy needed to digest, absorb, and metabolize nutrients. Proteins require the highest TEF (20–30%), followed by carbs (5–15%) and fats (5–15%)

Anabolism

Reactions that build up more complex molecules from simpler ones. Examples include building proteins in transcription or building glycogen from glucose

Catabolism

Reactions that break down complex molecules into smaller molecules. Examples include digestion or breaking down glycogen into glucose

Law of Conservation of Energy

The principle that energy cannot be created or destroyed, only transferred. In the body, this means Caloric Intake must balance TEE

"Calories In, Calories Out" Limit

While based on the Law of Conservation of Energy, this concept is limited because the human body is extremely complicated; cutting Calories can slow down metabolism

"Negative Calorie Food"

A myth (false). The idea is that it takes more energy to digest the food (like celery or grapefruit) than it provides to the body. These foods are healthy because they are high in fiber

Exercise

A subset of physical activity that is planned, structured, and repetitive. Examples include running, weight lifting, yoga, gardening, and dancing

Aerobic Exercise ("Cardio")

Longer interval exercise that allows oxygen to reach your muscles (i.e., "with oxygen").

Examples include distance running, cycling, swimming, and yoga. Calories come from a balance of fat and glycogen

Anaerobic Exercise

Intense, short burst exercise that does not allow oxygen to reach muscles fast enough (i.e., "without oxygen").

Examples include weightlifting at maximum and sprinting. Most Calories come from glycogen

Strength Training

Very important, especially for older women at risk of osteoporosis. It should be included at least two days a week

Muscular Dysmorphia ("Bigorexia")

Characterized by an obsessive and compulsive desire to grow bigger muscles through excessive weight training. This condition mainly affects adolescent boys and young men

Anabolic Steroids

Chemicals that mimic testosterone to promote muscle growth. Their use is increasing, almost exclusively in teenage boys and young men, often fueled by social media personalities

Excessive Exercise

Exercise that is bad for health, leading to injury. It is the fastest growing eating disorder (especially in younger men/teenage boys) and often arises from body dysmorphia

Diet

The kind of food that an individual organism habitually eats (not an occasional thing).

Weight and Health

Not a one-to-one comparison; an individual can be healthy or unhealthy at all body sizes.

Dietitian (Registered Dietitian)

A regulated term for a medical professional who must have a graduate degree in dietetics plus 1,000 service hours

Nutritionist

Not a regulated term; anyone can call themselves this, and they often make money selling a course or a diet. Credentials must be verified.

Keto Diet

A restrictive diet aiming for ketosis by decreasing carbohydrates and increasing fat and protein intake. Originally for epilepsy. Cons include raising LDL cholesterol and weakening bones.

Mediterranean Diet

The most extensively-studied diet. Focuses on high intake of fruits, vegetables, grains, olive oil, and communal eating. Pros include raising HDL and lowering the risk of type 2 diabetes and cancer.

Complete Proteins

Protein sources containing all 9 essential amino acids, such as meat, dairy, eggs, soy, quinoa, and buckwheat

Tertiary Processed Foods

Foods that are artificially high in saturated fats, trans fats, sugar, and sodium, and are generally better to avoid.

Healthy Diet

A diet that includes a diverse intake of vegetables, fruits, grains, meats, and unsaturated fats, providing enough Calories, good fiber and protein, and low sodium

calorie intake (what you eat)

carbs, protein, fat

total energy expenditure (tee)

rmr, physical activity, tef

mifflin st. jeor equation

men: 10 x W (kg) + 6.25 x H (cm) - 5 x A (years) + 5 = BMR
women: 10 x W (kg) + 6.25 x H (cm) - 5 x A (years) - 161 = BMR

processes of metabolism

anabolism + catabolism

examples of metabolism

■ Building proteins in transcription

■ Building glycogen from glucose

■ Making ATP from ADP and phosphate

examples of catabolism

■ Digestion

■ Breaking down of glycogen into glucose

two main types of exercise

• aerobic

• anaerobic

What type of exercise (aerobic or anaerobic) is weightlifting at maximum?

Weightlifting at maximum is anaerobic exercise. Anaerobic exercise is defined as intense, short burst exercise that does not allow oxygen to reach muscles fast enough

What is one factor that affects your metabolism?

One factor that affects your metabolism is Body mass (both height and weight). Other factors include age, level of activity, genetics, medication, diseases, and sleep

What type of exercise (aerobic or anaerobic) is jogging for 30 minutes?

Jogging for 30 minutes would primarily be aerobic exercise.