Sport Nutrition second half

Essential nutrients (can’t synth all that we need), required in small amounts for health

Organic micronutrients essential for a specific organism Cannot be synth so must be obtained from the diet Minerals Essential inorganic micronutrients

D can be synth in skin from cholesterol with exposure to UV Vitamin K synthesised by some gut bacteria

B complex (12 different vitmaines C

A (found in lliver, known as retinoids) E,D,K

Energy metab B complex - lots of citric acid cycle components, part of NAD and B5 CoA? Antioxidants A,C,E Synthesis of body components Collagen Vit C Hormones Vit C (norepinephrine) Bone Vit D, A Blood clotting factors Vit K Visual pigment Vit A

15 inorganic elements Minerals - required in amounts >100mg.day Ca, P, Mg, K, Fe, Na, Zn, Cl Trace Elements - required in <20mg.day (others)

Structure Bone and teeth Most abundant - Ca, P, Mg Function Soluble salts responsible for body fluid osmolality and determination of ICF and ECF volume Na, K (more ICF), Cl, Mg, Ca Maintain normal heart rhythm, muscle contractibility, neural conductivity Regulation Components of proteins (hormones and enzymes) I and thryroxine Fe, Cu, Zn components of enzymes/ cofactors

Prevent of limit damaging effects of free radicals in the body (intra and intercellularly) Atoms or molecules with 1 or more unpaired electron Most common are reactive oxygen species (ROS)

Aerobic resp - intermediates in normal reactions WBCs-ROS for invading pathogens Hypoxia e.g. HIIT Radiation and pollution Smoking UV Inflammation

SOD (o2 -> H2O2) Catalase (h2O2 = H2O and O2) Gluathione peroxidase

Non enzyme Vit E - major lipid soluble antioxidant Protects membranes from oxidative damage Vit C Aqueous components of body Flavonoids and carotenoids

Antioxidants in skeletal muscle fatigue =Inability of muscle to generate force Radical production may play a role ROS increases in contracting skeletal muscle Excessive ROS induces oxidative damage to muscle proteins and reduces force production Mostly from animal studies - antioxidants protect skeletal muscle from damage and delay fatigue during prolonged submax exercise No effect on high intensity

Exercise can be prolonged with N-acetylcysteine infusion (NAC) - antioxidant 70% VO2 max at 45 min then fatigue at 92% VO2max - time increases by miunutes Little evidence that dietary antioxidants could make a difference e,g, E, C, betacarotene

Most common are not toxic so no harm Radicals promote fatigue in skeletal msucel NAX attenuates Inadequate dietary intake e.g. Restriction, poor diet, increased training

Exercise oxidative stress -no evidence it harms health Exercise increases antiocidants (both kinds) in skeletal muscle) If dietary intake sufficient, supplementation likely not needed Might impair adaptation of muscle to exercise ROS signal to promote expression of skeletal muscle proteins Antioxidant enzymes, mitochondiral proteins and heat shock proteins

198 US olympic athletes asked 2 questions Would they take performance enhancing drugs if, Guarenteed to win every comp for 5 years Guaranteed notto get caught 98% yes Would they take performance enhancing frugs if: Same But guarenteed death from side effects 52% said yes 1992

Athletes more concerned about legality than death

If it works, its banned If it doesnt work, its not banned Few exceptions

Aid recovery Health Improve performance Prevent. Treat illness. Compensate poor diet Most high level take 80-90% track and field

If eliminated food group e.g. Vegan If put into energy deficit - may need supplements Need extra valories/ carbs

Risk of contamination increases Potential detriment to performance

Ergogenic Ergo=work Genic=making Creatine - from meat, veges better Beta-alanine/carnosine - only is turkey (eat lots for sufficient amount) Biocarbonate Caffeine? - some from foods Nitrate? - some foods e.g. beetroot Sports food Protein Carb - tablets, drinks

Females