Hvilken effekt vil udholdenhedstræning have på oxidative enzymer?
Endurance training
Langvarig udholdenhedstræning inducerer mange fysiologiske tilpasninger både centralt og perifert medieret. De centrale kardiovaskulære tilpasninger omfatter nedsat puls, øget slagvolumen i hjertet, øget blodplasma uden større ændringer i antallet af røde blodlegemer, hvilket reducerer blodets viskositet og øget hjerteydelse samt øget samlet mitokondriel volumen i de muskelfibre, der anvendes i træningen (dvs. lårmusklerne hos løbere vil have flere mitokondrier end lårmusklerne hos svømmere). Mitokondrierne øges både i antal og størrelse, og der er tilsvarende stigninger i myoglobin og oxidative enzymer. Tilpasninger i det perifere område omfatter kapillarisering, dvs. en forøgelse af det overfladeareal, som både de venøse og arterielle kapillærer forsyner. Dette giver også mulighed for øget varmeafledning under anstrengende træning. Musklerne øger deres glykogen- og fedtlagringsevne hos udholdenhedsatleter for at øge den tid, de kan udføre arbejde. Ved udholdenhedstræning arbejdes der primært med de langsomme trækfibre (type 1), og disse fibre udvikles i deres effektivitet og modstandsdygtighed over for træthed. Katabolismen forbedres også, hvilket øger atleternes evne til at bruge fedt- og glykogenlagre som energikilde. Disse metaboliske processer er kendt som glykogenolyse, glykolyse og lipolyse. Der er større effektivitet i ilttransport og -fordeling. I de senere år er det blevet erkendt, at oxidative enzymer som f.eks. succinatdehydrogenase (SDH), der gør det muligt for mitokondrier at nedbryde næringsstoffer for at danne ATP, stiger 2,5 gange hos veltrænede udholdenhedsatleter Ud over SDH stiger myoglobin med 75-80 % hos veltrænede udholdenhedsatleter.
Long-term endurance training induces many physiological adaptations both centrally and peripherally mediated. Central cardiovascular adaptations include decreased heart rate, increased stroke volume of the heart, increased blood plasma, without any major changes in red blood cell count, which reduces blood viscosity and increased cardiac output as well as total mitochondrial volume in the muscle fibers used in the training (i.e. the thigh muscles in runners will have more mitochondria than the thigh muscles of swimmers). Mitochondria increase in both number and size and there are similar increases in myoglobin and oxidative enzymes. Adaptations of the peripheral include capillarization, that is an increase in the surface area that both the venous and arterial capillaries supply. This also allows for increased heat dissipation during strenuous exercise. The muscles heighten their glycogen and fat storing capabilities in endurance athletes in order to increase the length in time in which they can perform work. Endurance training primarily work the slow twitch (type 1) fibers and develop such fibers in their efficiency and resistance to fatigue. Catabolism also improves increasing the athletes capacity to use fat and glycogen stores as an energy source. These metabolic processes are known as glycogenolysis, glycolysis and lipolysis. There is higher efficiency in oxygen transport and distribution. In recent years it has been recognized that oxidative enzymes such as succinate dehydrogenase (SDH) that enable mitochondria to break down nutrients to form ATP increase by 2.5 times in well trained endurance athletes In addition to SDH, myoglobin increases by 75-80% in well trained endurance athletes.
Endurance training