Unit 13 Exercise and Immunity

what is the immune system?

protects the body against infectious disease it is involved in tissue repair and protection against potential pathogens

what are the two types of immune system?

innate and adaptive

What is the innate immune system?

immune system that's present before any exposure to pathogens and is effective from birth

what is the adaptive immune system?

develops only after exposure to microbes, toxins and other foreign objects

what are the three types of defence in the innate immune system?

physical defence - skin, epithelial lining, mucosal secretion
chemical defence - PH of bodily fluids, hormones, other soluble factors
leucocytes - WBC's fight infection

what are the three types of defence in the adaptive immune system?

1. inflammation
2. blood clotting
3. phagocytes and antibody production

how does inflammation occur?

1. histamine is released when the body detects that defences have been damaged and pathogens have entered.
2. this causes capillary permeability to increase causing redness, swelling and heat

how does blood clotting occur?

platelets responsible for clotting leave the capillary and a clot form to close the wound and prevent pathogens entering

how do lymphocytes and antibodies attack pathogens/prevent them?

1. leucocytes attack pathogens
2. foreign antigens are detected
3. specific antibodies are released from B cells then they bind to the antigen
4. then phagocytes engulf dead antigen
5. T cells and B cells produce memory cells with antibodies so if the pathogen re-enters it will destroy it quickly

what immune function does a sedentary person have?

low/medium

why are sedentary people more susceptible to illness?

poor circulation - preventing free movement of cells and substances - prevents fighting the disease

what immune function does an active person have?

high

why are active people less susceptible to illness?

- better circulation
- cardiac hypertrophy
- healthier blood vessels
- boosts every immune function

what immune function do over trained people have?

very low - lower than sedentary

why are overactive people more susceptible to illness?

- lower leucocyte (WBC) counts caused by stress of exercise
- inflammation of muscles from exercise prevents blood flow causing stress
- deep breathing during exercise causes bacteria to be inhaled
- sustained adrenaline levels cause suppression to immune system
- cortisol hormone (stress) supresses immune system

name some strategies to minimise the risk of infection

good hygiene - hands, skin, hands to mouth, coughing
rest - sufficient recovery time
relationships - avoids those with illnesses
diet - variation, hydration, vitamins and minerals