Exercise and the Immune System

Question 1

Immunity

Answer 1

mechanisms used in the body to protect against foreign agents

Question 2

immune system

Answer 2

physical, cellular, and chemical components that create redundancy in protection

Question 3

What are the three layers of the immune system?

Answer 3

• physical barriers (skin, mucous membranes, enzymes, microbiota)
• innate immune system
• adaptive immune system

Question 4

Describe the innate immune system.

Answer 4

nonspecific

Question 5

Where are all blood cells made?

Answer 5

in the bone marrow from stem cells

Question 6

What are the cells on the innate immune system?

Answer 6

• leukocytes
• macrophages
• neutrophils
• NK cells

Question 7

leukocytes

Answer 7

• (WBC) recognize and remove foreign invaders
• circulate in the blood and tissues

Question 8

Macrophages and neutrophils

Answer 8

engulf foreign agents (phagocytosis), kill, and remove them

Question 9

NK cells

Answer 9

• cells stored in blood, liver and spleen
• destroy infected cell, parasites, cancer cells

Question 10

cytokines

Answer 10

chemical messengers secreted by immune cells (macrophages, neutrophils, NK cells)
* can activate or attract other immune cells
* increase blood flow to area of infection (redness, swelling, heat, pain)
* mediate fever responses

Question 11

autocrine

Answer 11

self-signaling

Question 12

paracrine

Answer 12

signaling nearby cells

Question 13

endocrine

Answer 13

signaling distant cells through blood

Question 14

Pro-inflammatory cytokines action

Answer 14

• increase inflammation
• increase immunity
• pathogen killing

Question 15

pro-inflammatory cytokines endpoint

Answer 15

• chronic inflammation
• scarring
• fibrosis

Question 16

examples of pro-inflammatory cytokines

Answer 16

IL-1, IL-6, IL-12, TNF-alpha

Question 17

anti-inflammatory cytokine actions

Answer 17

• decrease inflammation
• angiogenesis
• matrix proliferation
• decrease apoptosis

Question 18

anti-inflammatory cytokine endpoint

Answer 18

• cellular replacement
• tissue regeneration
• ECM remodeling

Question 19

Examples of anti-inflammatory cytokines

Answer 19

IL-10, TGF-beta

Question 20

complement proteins

Answer 20

produced by the liver and are present in high concentrations in blood and tissues

Question 21

What are the three main functions of the complement system?

Answer 21

• form ‘membrane attack complexes’: attach to surface of foreign cells to bore a channel into cell membrane which kills the cell
• tag cells as foreign so other components of the innate immune system recognize and attack
• serve as a chemoattractant

Question 22

adaptive (acquired) immunity

Answer 22

plays a large role in fighting viruses; made up of B- and T-cells

Question 23

B cells

Answer 23

• produce antibodies against antigens (or allergens)
• activate compliment cascade
• neutralize viruses
• attract other immune cells

Question 24

T-cells

Answer 24

mature in the thymus; specialize in recognizing protein antigens
* killer t cells
* helper t cells
* regulatory t cells

Question 25

killer t cells

Answer 25

recognize and kill virus-infected cells

Question 26

helper t cells

Answer 26

secrete cytokines; coordinate response

Question 27

regulatory t cells

Answer 27

inhibit response; particularly to self antigens

Question 28

How are training volume and immune function related?

Answer 28

J-shaped curve with chronic exercise training intensity * mostly based on upper respiratory tract infections * evidence is strongest for aerobic training

Question 29

open window theory

Answer 29

after intense exercise increased susceptibility to illness

Question 30

overtraining syndrome

Answer 30

unexplained decrease in performance for weeks, months, or years * cannot be remedied by short-term decrease in training or rest * can occur with all forms of training * not all fatigue is caused by overtraining

Question 31

Overtraining syndrome symptoms

Answer 31

* decreased strength, coordination, exercise capacity * fatigue * change in appetite; weight loss * sleep and mood disturbances * lack of motivation, vigor or concentration high individualized and subjective; necessary to rule out other causes

Question 32

When is overtraining syndrome more likely to occur?

Answer 32

when training at high volume and intensity for long periods of time

Question 33

psychological factors of overtraining syndrome

Answer 33

* emotional pressure of competition --> stress * parallels with clinical depression

Question 34

# Overtraining Syndrome Autonomic/Endocrine

Answer 34

* greater swings in sympathetic/parasympathetic activity * increased resting catecholamines * decreased resting thyroid hormone and testosterone levels * increased resting cortisol

Question 35

# Overtraining Syndrome Testosterone to cortisol ratio

Answer 35

* proposed as an indicator of anabolic recovery processes * linked to protein catabolism changes

Question 36

# Overtraining Syndrome Immune Response

Answer 36

overtraining suppresses immune function * decreased number of lymphocytes * decreased production of antibodes by B cells * increased incidence of illness after exhaustive exercise (longer open window)

Question 37

# Overtraining Syndrome Circulating cyotkines

Answer 37

increase during periods of physical stress + decreased rest * increase in response to muscle, bone, joint trauma * persistent increase in circulating cytokines --> inflammation --> associated with overtraining symptoms

Question 38

# Overtraining Syndrome Treatment

Answer 38

* reduced intensity * rest (weeks, months) * stress management

Question 39

# Overtraining Syndrome Prevention

Answer 39

* periodization training * adequate caloric intake (especially carbohydrate)