Exhaustive physical activity is associated with increased production of reactive oxygen species and oxidative stress. Enhanced free radical production leads to cellular loss of redox homeostasis and might result in muscular injury, soreness, and fatigue, and, consequently, decrements in physical performance. Methods to reduce free radical production and subsequent oxidative stress and muscle damage during and following physical exercise have been a priority of much research activity. Various antioxidants and their combinations were investigated. Astaxanthin is one of the main pigments belonging to the family of the xanthophylls, which is generally distributed in seafood. Recent studies continue to evidence the multiple possibilities of astaxanthin application in providing benefits to human health. The physiologic stress induced by prolonged and intensive exertion is reflected in transient yet significant immune system perturbations in multiple body compartments. The influence of several nutritional countermeasures to exercise-induced alterations of mucosal immunity have been investigated including carbo-hydrate, zinc, glutamine, bovine colostrum, caffeine, as well as several antioxidants. The purpose of the present investigation was to determine the effects of astaxanthin supplementation on oxidative stress and muscle damage in young soccer players while following their habitual dietary pattern and training program during competitive season. In addition, the effect of couple nutritional measures (sensory stimulation and astaxanthin supplementation) on mucosal immunity were investigated The study was performed in a group of 40 soccer players, 28 high school pupils, who did not practice intensive physical exercise regularly and 20 subjects who practiced karate recreationally. The study was conducted according to the guidelines laid down in Declaration of Helsinki. Experimental procedures were approved by the Ethical Committee of Sports Medicine Association of Serbia. Long-term soccer training is accompanied by an increased capacity of antioxidant systems. However, soccer players are exposed to higher level of oxidative stress in comparison to sedentary people. Soccer exercise is associated with excessive production of free radicals and oxidative stress which might diminish total antioxidant status. Supplementation with astaxanthin could prevent exercise induced free radical production and depletion of non enzymatic antioxidant defense in young soccer players. Regular soccer training over the period of 90 days provokes increased production of superoxide anion and decreased activity of superoxide dismutase. On the other hand, soccer training may result in decreased total oxidant status and prooxidant-antioxidant balance, probably due to an up regulation in the body's antioxidant defense system. Astaxanthin supplementation had beneficial effect on improving paraoxonase 1 activity toward paraoxon and diazoxon, as well as total sulphydryl groups content in young soccer players. Supplementation with astaxanthin might stabilize sarcolemma leading to less muscle damage. Intensive soccer exercise, as well as recreational karate exercise induced decrease in sIgA absolute concentration and sIgA secretion rate and the magnitude of these alterations reflects the intensity, duration and chronicity of the exercise. Application of flavored whey-based drink elevated salivary flow and might be helpful in maintenance of total sIgA amount covering mucosal surface. Astaxanthin might have beneficial effect on sIgA production in saliva in young soccer player during training season. Intenzivni treninzi dovode do povećanja produkcije slobodnih radikala i mogu doprineti nastanku oksidativnog stresa kod sportista. Pored toga, poremećaj ćelijske homeostaze u mišićima uzrokovan slobodnim radikalima rezultira oštećenjem mišića, bolom, zamorom i smanjenjem sportskih performansi. Do sada je sproveden veliki broj istraživanja sa ciljem da se odredi efekat antioksidanasa na smanjenje oksidativnog stresa i oštećenja mišića, koje nastaju kao posledice intenzivne fizičke aktivnosti. Astaksantin (Asx) je liposolubilna supstanca koja pripada grupi ksantofila, oksidovanih derivata karotenoida, široko rasprostranjen u prirodi. Rezultati do sada sporovedenih istraživanja pokazuju da astaksantin, zbog izvanredne antioksidativne aktivnosti, može imati značajnu ulogu u ishrani ljudi u cilju očuvanja zdravlja i prevenciji hroničnih bolesti. Fiziološki stres uzrokovan dugim i intenzivnim treninzima se ogleda i u prolaznim, ali značajnim promenama u imunom sistemu što se dovodi u vezu sa povećanom incidencom infekcija, naročito infekcija gornjih respiratornih puteva kod sportista. Do sada je ispitivan uticaj nekoliko nutritivnih mera na promene u imunom sistemu uzrokovanih intenzivnim treninzima: ugljeno-hidratni napici, omega-3 masne kiseline, razni antioksidansi, cink, glutamin, ehinacea i kolostrum, meĊutim čvrstih dokaza za efikasnost ovih suplemenata još uvek nema. Stoga je cilj istraživanja bio ispitivanje uticaja suplementacije Asx na oksidativni stres i oštećenje mišića kod mladih fudbalera u toku sezone. Pored toga, ispitivan je i uticaj suplementacije Asx i senzorne stimulacije aromatizovanim napitkom na bazi surutke na mukozni imunitet sportista. U istraživanju je učestvovalo 40 fudbalera, 28 ispitanika koji nisu imali redovnu intenzivnu fizičku aktivnosti i 20 ispitanika koji su se rekreativno bavili karateom. Studija je planirana u skladu sa etičkim standardima datim u Helsinkiškoj deklaraciji i u skladu sa pravilima Etičkog komiteta Udruženja za medicinu sporta Srbije. Dugogodišnje treniranje fudbala uslovljava povećanje aktivnosti antioksidativnih mehanizama zaštite, ali su i pored toga mladi fudbaleri izloženi većem nivou oksidativnog stresa i oksidativnog oštećenja u odnosu na fizički neaktivne osobe. Intenzivni fudbalski trening je povezan sa povećanom produkcijom slobodnih radikala, što može smanjiti totalni antioksidativni status. Suplementacija astaksantinom može delimično sprečiti povećanu produkciju slobodnih radikala i trošenje neenzimske antioksidativne zaštite kod mladih fudbalera. Naporan program treniranja u toku sezone dovodi do povećanja produkcije superoksidnog anjona i smanjenja aktivnosti enzima superoksid dizmutaze. Ipak, uočeno smanjenje totalnog oksidativnog statusa i prooksidativno-antioksidativnog balansa, ukazuje na smanjenje nivoa oksidativnog stresa, što je verovatno posledica adaptivnog odgovora na intenzivne treninge. Suplementacija astaksantinom ima povoljan efekat na unapređenje aktivnosti enzima paraoksonaze 1 i ukupan sadržaj sulfhidrilnih grupa kod mladih fudbalera. Primena astaksantina u toku sezone može stabilisati mišićnu membranu i na taj način smanjiti oštećenje mišićnih ćelija do određenog stepena. Intenzivan trening kod fudbalera, ali i rekreativni karate trening dovode do pada nivoa sekretornog IgA u salivi. Primena aromatizovanog napitka na bazi surutke nakon treninga može biti od koristi u cilju održavanja salivarnog protoka, a na taj način i količine sIgA u salivi. Rezultati pokazuju da suplementacija astaksantinom može imati povoljan efekat na produkciju sIgA u salivi kod mladih fudbalera u periodu intenzivnih treninga tokom sezone.