L10: Lose It (Sedentary Lifestyle)

Question 1

Sedentary behaviour

Answer 1

Any waking activity characterized by an energy expenditure ≤ 1.5 METs, often done in a sitting or reclining position

Question 2

Why are a greater proportion of people now engaged in sedentary behaviour?

Answer 2

Most work (espically in developed nations) is based on cognitive labour.

Furthermore, most leisure activities are now spent sitting or lyind down watching a screen

Question 3

How does high mental work affect blood glucose levels?

Answer 3

High mental work causes high fluctuations in blood glucose levels as the brain primarily uses glucose as its form of energy

Question 4

What sort of food do people desire when they have low levels of blood glucose?

Answer 4

Energy dense foods that can cause weight gain if consumed in excess

Question 5

What 2 effects does sedentary behaviour have on the muscles?

Answer 5

1. Decreased muscle mass
2. Decreased glucose uptake into muscles

Question 6

What 2 effects does increased blood glucose and adiposity have on the vascular system?

Answer 6

1. Increased inflammation
2. Insulin resistance

Question 7

Once the muscles and liver’s glycogen stroes are full, where does excess glucose go?

Answer 7

To adipose tissue where glucose is stored as fat in a process called de novo lipogenesis

Question 8

Sacropenia

Answer 8

Muscle atrophy and increased intramuscular fat in ‘anti-gravity’ muscles

Question 9

In what demographic of the population was sacropenia most common in?

Answer 9

Sacropenia used to be most common in elderly people but is now common among youth and middle aged people

Question 10

How does sedentary behaviour affect the bones?

Answer 10

Sedentary behaviour reduces bone-mineral density, casuign postural changes and increased risk of bone fractures

Question 11

Osteopenia

Answer 11

A reduction in bone mineral density that is usally followed by osteoporosis

Question 12

How much reduction in bone-mineral density occurs after 12 weeks of bed rest?

Answer 12

1-4%

Question 13

What 4 effects does sedentary behaviour have on the vascular system?

Answer 13

1. Increased blood lipids
2. Increased blood glucose
3. Increased insulin resistance
4. Increased inflammation and oxidative stress

Question 14

Why are constricted blood vessels and increased blood pressure dangerous?

Answer 14

They increase the risk of CVD (blood clots, heart attacks, strokes, etc)

Question 15

What 2 effects does smoking have on the vascular system?

Answer 15

1. Constricts blood vessels
2. Increases oxidative stress

In combiantion with sedentary behviour, smoking significantly increases a peron’s risk of CVD

Question 16

How does sedentary behaviour affect the central nervous system and psychological health?

Answer 16

It decreases neuroplasticity and may put people at a higher risk of mental illnesses like depression

Question 17

What small lifestyle changes can people make to reduce sedentariness?

Answer 17

More walking, less screen time, taking the stairs, particiapting in physically active hobbies, etc

Little movements matter, they accumualte throughout the day