Illness in athletes and how to avoid them Flashcards
Explain the relevance of the J shaped model (Neiman 1994)
High intensity exercise is associated with an above average number of colds per year
What was the finding of Neiman et al 1990 study into illness in marathon runners
1 week after running the LA marathon, runners were 6 times more likely to experience a control than controls
positive correlation between OR of having URTI and km/week of training
What were the findings of Bury et al 1998 in a study into illness in footballers
77% of illness was during the cold season which is also when there is fixture congestion
players had more coughs and colds which also lasted longer vs playing staff
Outline the reasons why athletes have an increased exposure to pathogens
Increased rate of lung ventilation
Breath through mouth so bypass protective processes in nose
skin abrasions in certain sports
foreign travel so newly encountered pathogens
long haul flights with re-circulated air
crowds with new pathogens
team showers so pathogens in warm enviroment
Why do city marathon runners have an increased risk of becoming ill vs other athletes
increased pollution in the air
pollutants decrease the immune response in the lungs
Give reasons why athletes may be immune supressed
Physiological and psychological stress
enviromental stress e.g temperature
Inadequate diet (too much protein not enough carbs)
lack of sleep
What are the acute effects of exercise on the immune system and what is the implication of this
Elevated leukocyte count, but supressed function
elevated count means less are available later if needed
Need to allow adequate recovery time so leukocyte function can be restored, otherwise chronically supressed
What are the chronic effects of exercise on the immune system
Lower resting leukocyte count
decreased leukocyte function
supressed antibody function (IgA)
What is the importance of salivary IgA in relation to URTI
Low levels or poor salivary flow rates are associated with increased incidence of URTI
What were the findings of Gleeson 1999 in relation to salivary IgA
Inverse association between resting amount of salivary IgA and number of infections
Results demonstrated a substantial contribution for one aspect of the immune system alone
What were the findings of Engles and Fahlman 2005 when comparing American college Footballers and non-playing controls
controls = relativly constant IgA levels
Footballers = fall in IgA in autumn and spring which is also when training hardest and had most matches
Dip in IgA coincided with peak of infections with >50% having infection at this time
Explain the methods of Neville et al 2008
Found each athletes average natural level of IgA
then took IgA sample each week to find % of average IgA
documented when athlete had an infection
What were the findings of Neville et al 2008
low IgA = more colds
before a cold, levels of IgA were falling
40% fall in IgA = 50% chance of cold
How can the findings of Neville et al 2008 be used
Coaches can see when athlete IgA is falling and then implment stratergies or alter training load to decrease chance of infection developing
What is the limitation of trying to reduce transmission of pathogens as a way of decreasing infections
No always the easiest to implement in day to day work during sport
Name ways by which an athlete can maintain an healthy immune system
Allow sufficient recovery time
avoid micronutrient deficiency
Ingest carbohydrates during exercise
Daily probiotic and Vit D supplement
What ways can an athlete be better managed to decrease their chances of infection
Monitor mood monitor fatigue levels avoid prolonged training sessions allow recovery days vaccination
what was the link between salivary IgA and fatigue, described by Neville et al 2008, and how can this be used by coaches
As level of perceived fatigue increases there was a significant decrease in salivary IgA
Can monitor fatigue levels as an indicator of likelyhood of illness rather than IgA bc this is easier to do
Bishop et al 2005
Participants did shuttle runs over 2 days and were then exposed to flu virus
One group consumed carb drinks during shuttle runs, other didn’t
carb consumers had restored immune function at start of day 2 whereas non consumers was decreased
immune function was anti-viral cells
Bishop et al 2009
2 hour run at 60%V02max
carb vs placebo drink
measured CD4 migration to infected lung cells
carb group migration rates fell to 80%
placebo group fell to 40%
Gleeson and Bishop 2011 (probiotic)
Daily probiotic vs placebo drink for 16 weeks during winter training for endurance athletes
proportion of athletes with cold decreased in probiotic group
potentially due to preventing season fall in salivary IgA
Gleeson and Bishop 2013 (Vit D)
catagorised people as optimal, adequate, inadequate or deficient in Vit D
as levels decreased, incidence and severity of infections increased
salivary IgA also higher in optimal group so potential link there
Prather et al 2105 (sleep)
Innoculated people and then monitored amount of sleep they got
those sleeping for less than 5 hours or for 5-6 hours were 4x more likely to get a cold than those sleeping for 7 hours
Cox et al 2008 (non-infectious)
40% of athletes having cold symptoms actually had an allergy
once known, very easy to treat.
