Australian Mountain Bike - - Contents - WORDS: JENNI KING PHO­TOS: ROBERT CONROY

We are now well into win­ter and with the cooler weather the dreaded cold and flu sea­son has ar­rived. This time of year is when I usu­ally find rid­ers are forced to take ex­tended breaks from train­ing due to viruses, in­fec­tions, stom­ach bugs etc. In the news you will hear warn­ings for those sec­tors of the com­mu­nity most at risk of con­tract­ing the flu virus. Gen­er­ally this in­cludes the el­derly, ba­bies and preg­nant women. Ac­cord­ing to sports medicine ex­perts, en­durance ath­letes should also be con­sid­ered in this “high risk” cat­e­gory due to low­ered im­mu­nity fol­low­ing pro­longed stren­u­ous ex­er­cise. In par­tic­u­lar, en­durance ath­letes are sus­cep­ti­ble to con­tract­ing Up­per Res­pi­ra­tory Tract in­fec­tions (URTIs) in­clud­ing the com­mon cold, si­nusi­tis and ton­sil­li­tis. While mod­er­ate ex­er­cise has been shown to re­duce in­ci­dence of URTI, ex­ces­sive ex­er­cise can have a neg­a­tive ef­fect on Im­mune Sys­tem func­tion. ‘After stren­u­ous ex­er­cise, ath­letes en­ter a brief pe­riod of time in which they ex­pe­ri­ence weak­ened im­mune re­sis­tance and are more sus­cep­ti­ble to vi­ral and bac­te­rial in­fec­tions, in par­tic­u­lar URTIs. Post-ex­er­cise im­mune func­tion de­pres­sion is most pro­nounced when the ex­er­cise is con­tin­u­ous, pro­longed (>90 min­utes), of mod­er­ate to high in­ten­sity (55-75% of aer­o­bic ca­pac­ity), and per­formed with­out food in­take’ *(Glee­son et al. 2013). Suf­fer­ing through sick­ness is never fun for any­one and the longer an ath­lete is un­able to train due to sick­ness the less fit­ness gains can be made. While a few days off the bike due to a virus isn’t go­ing to make a huge dif­fer­ence to over­all fit­ness, when an ath­lete is forced to take a week or more off train­ing, or is hav­ing to take numer­ous days off ev­ery few weeks, this can put a huge dent in their prepa­ra­tion for the race sea­son ahead. In this ar­ti­cle I have ex­plained the main causes of in­creased in­fec­tion rates amongst cy­clists and, most im­por­tantly, what can be done to min­imise your risk of con­tract­ing such in­fec­tion.


Due to the in­creased rate and depth of breath­ing, ath­letes are ex­posed to higher lev­els of pathogens in the en­vi­ron­ment. Some of the symp­toms re­ported are due to non-in­fec­tious air­way in­flam­ma­tion caused by cold air, al­lergy and/or pol­lu­tants. How­ever, the ma­jor­ity of symp­toms are caused by true vi­ral/bac­te­rial in­fec­tions. As well as dur­ing train­ing, ath­letes are also ex­posed to in­creased lev­els of pathogens when they travel to races (par­tic­u­larly dur­ing flights), and when sur­round­ing them­selves with other ath­letes prior to races. It is not un­com­mon for en­tire Na­tional teams to come down with vi­ral in­fec­tions when stay­ing to­gether prior to big events and is one rea­son why many ath­letes have cho­sen to iso­late them­selves prior to com­pet­ing at World Cham­pi­onships and Olympic Games in re­cent years. To de­crease your risk of air­borne pathogen ex­po­sure make sure to take the fol­low­ing pre­cau­tions: - Avoid con­tact with in­fec­tious peo­ple, par­tic­u­larly those “just com­ing down with some­thing”. Young chil­dren who have just started child­care/school are par­tic­u­larly risky to be around. - Keep on top of per­sonal hy­giene – wash­ing

hands, us­ing hand san­i­tizer etc. - Avoid shar­ing drink bot­tles. - Make sure the water you are drink­ing (or swim­ming in) is not con­tam­i­nated and drink bot­tles are cleaned well be­fore use. - Avoid shared saunas, spas, show­ers where pos­si­ble – bac­te­ria love warm, moist en­vi­ron­ments. - Keep hy­dra­tion lev­els high to avoid dry

mouth and throat. - Make sure to dress ap­pro­pri­ately for hot

and cold ex­tremes in tem­per­a­ture.


Dur­ing and post-ex­er­cise, lev­els of cer­tain hor­mones such as cor­ti­sol, adren­a­line, growth hor­mone and pro­lactin will in­crease. While this will largely have a pos­i­tive ef­fect on mood, mus­cle growth and fat me­tab­o­lism, an in­crease in such hor­mone lev­els has also been shown to have a neg­a­tive ef­fect on the im­mune sys­tem and its abil­ity to fight in­fec­tion. There is def­i­nitely a “win­dow of time” im­me­di­ately after heavy ex­er­cise where cir­cu­lat­ing hor­mones are high and im­mune sys­tem is sup­pressed. Dur­ing this win­dow it is ex­tremely im­por­tant to take mea­sures to bring the body back to home­osta­sis. Post work-out nutri­tion and hy­dra­tion is very im­por­tant, as well as ad­e­quate cool-down and of course rest/sleep.


Glutamine is an amino acid found in blood plasma and skele­tal mus­cle tis­sue which aids in mus­cle re­pair and im­mune re­cov­ery. Pro­longed and/or heavy ex­er­cise has shown to be as­so­ci­ated with de­creased lev­els of plasma glutamine con­cen­tra­tion. With a con­sid­er­able drop in Glutamine lev­els post train­ing, the im­mune sys­tem is un­able to work to full ca­pac­ity and as a re­sult ath­letes are sus­cep­ti­ble to in­fec­tion. It can take up to 24 hours for the body to re­plen­ish glutamine lev­els post ex­er­cise. Many stud­ies have shown that sup­ple­men­ta­tion of Glutamine straight after ex­er­cise will re­plen­ish stores a lot faster and there­fore aid mus­cle re­cov­ery and boost im­mune sys­tem func­tion. The sports in­dus­try is flooded with Glutamine sup­ple­ments. If you chose to use one, just be sure that it is ap­proved by the Aus­tralian Sports Anti-Dop­ing As­so­ci­a­tion (ASADA).


Cy­clists who have been train­ing at high loads for long pe­ri­ods of time have been shown to have low lev­els of cir­cu­lat­ing Leuko­cytes and higher than av­er­age lev­els of Neu­trophils. This re­sults in the de­ple­tion of bone mar­row re­serves and im­muno­sup­pres­sion. The ef­fect of in­creas­ing train­ing load too quickly has been shown to be even more detri­men­tal to bone mar­row and the abil­ity of lym­pho­cytes to re­spond to for­eign ma­te­rial. Make sure to plan and mon­i­tor your train­ing loads care­fully. Re­mem­ber that train­ing should be pe­ri­odised and re­cov­ery pe­ri­ods are just as im­por­tant as hard train­ing blocks. Gen­er­ally, train­ing loads (in­ten­sity and/or du­ra­tion), should not be in­creased by more than 5-10% on a weekly ba­sis. It is of­ten as­sumed that ath­letes have su­pe­rior im­mune sys­tem func­tion due to high lev­els of ex­er­cise. While a cer­tain level of ex­er­cise can be ben­e­fi­cial to im­mune func­tion, pro­longed and in­tense ex­er­cise will sup­press the im­mune sys­tem and it is not un­com­mon for ath­letes to con­tract in­fec­tion, par­tic­u­larly dur­ing win­ter. Make sure to de­crease your risk of in­fec­tion by tak­ing the pre­cau­tions I have sug­gested above. That way your train­ing can re­main con­sis­tent through win­ter and you will there­fore start the sum­mer sea­son with a solid base of fit­ness and most im­por­tantly in good health! *Glee­son M, Bishop NC and Walsh NP (2013). Ex­er­cise Im­munol­ogy. Lon­don: Rout­ledge (Tay­lor and Fran­cis)

Newspapers in English

Newspapers from Australia

© PressReader. All rights reserved.