Sport Nutrition first half

PCR and ATP - Substrate level phosphorylation in 100m - glycogen store manipulation doesn’t benefit. Glycolytic in 800m (although always cross over) - little aerobic - turned into lactate Oxidative phosphorylation in marathon - most from carbs (85% of VO2 max for 2 hrs)

Anabolism Building block precursors into synthesised end products Uses ATP into ADP + Pi Nutritionist not just what synthesised but also what is used (ATP) e.g. in muscle contraction

Catabolism Carbs, lipids, amino acids (also nutriets from diet) + O2 Into H20 and CO2 Produces ATP

If someone wants to continue work (Muscular work = anabolism from contraction) they need catabolism - ATP resynthesis.

5

Educator Translator Bouncer

Protein 14kg Fat 10.5 Carbs muscl glycogen 0.4 (up to 1kg) Liver 0.1kg Blood glucose (0.01)

Energy intake Energy stores Energy expenditure 3 way interaction - increase or decrease in one impacts the other factors Increase intake = increase stores. Increase energy intake= increase in metabolism (dietary induced thermogenesis) and can increase exercise and other components of energy expenditure. E.g. Studies show no breakfast = less PA in morning. Gives flexibility, not all excess will be adipose. Adipose tissues releases leptin which changes appetite and potentially intake Stores also affect energy expenditure e.g. High glycogen stores and running further.

Loads of factors that affect intake- broadly envionment and lifestyle influencing cognition, reward, choice, mood, stress. Individual genetics and early life also affect at all stages. Total energy intake Composition of diet Satiety issues Amount & type of fibre Type of foods (energy density) Environmental/ sociological reasons e.g. Fitting in with a mate in the bar Also normally finish a ‘mars bar’ regardless of size so mars determines intake. Current weight and body comp Hormonal control of appetite, fat deposition Intake then influences energy expenditure metabolically LOOK: (nutrient sensing, muscle, liver, fat, gut) and impacts our future actions about energy intake and expenditure.

Similar factors affect energy expenditure Resting metabolic rate Activities of daily living Planned PA Intensity of PA Body comp Total energy intake and composition of kcals Genetics & inefficient energy cycles Intake then influences energy expenditure metabolically LOOK: (nutrient sens

BMR vs RMR. Rarely BMR. BMR - after sleep without walking (12 hrs). BMR = 4 hrs after,

Active person - rest day - proportion of RMR varies however RMR stays the same. DIT is typically 10% of intake regardless of intake. TEE gives a challenge to expenditure which fluctuates on daily basis.

RMR easily predicted by height, age and body comp. (differences only 10s of calories).

7kcal/g

x4.2

Protein 25-30% is used to process protein Carbs 6-8% Fat 2-3%

DIT varies with nutritional Protein 25-30% is used to process protein Carbs 6-8% Fat 2-3% High protein diet but same calories (less calories) Due to gluconeogenesis energy (de aminate and then convert to useful carb Some pass straight to TCA Straight to Acetyl CoA Ketosis - some converted to ketones (ketogenic diet) Interconversion processes cost energy Contrasts to glucose - glucose ready to use Fat some processes - e.g. B oxidation.

As carbs decreases (replaced with fat and protein) As carb decreases, effective calories decreases Theoretical plan not real life. Change in expenditure resultantly x

Energy balance = dietry intake - total energy expenditure. EB amount of dietary energy added or lost from energy stores after all the body's physiological systems have done all their work for the entire dat EB is an output from the body's physiological systems Negative = weight loss e.g. negative 2000

EA = Dietary intake - Exercise energy expenditure Amount of dietary energy remaining after exercise training for all other metabolic functions e.g. cellular maintenance and repair, thermoregulation, immunity, growth, reproduction EA is an imput to the body’s physiological systems Low energy availability should be avoided because it can impair performance and adaptation to training and may be harmful to brain, reproduction, metabolic and immune function and to bone health.

Total energy expenditure is decreasing due to decreased metabolism - physiological systems are being suppressed e.g. Downregulate protein turnover, bone turnover, reproductive system Low EA then dampening of physiological systems so becomes higher EB (still negative)

EA causes effects on physiological systems Under voluntary control EB is an effect of physiological systems, not under voluntary control, Does not indicate energy requirements for Health. EA is likely to put someone above or below EB. Both need to be considered.

Causes Women more at risk than men Reason often unrelated to sport Female athlete triad Harmful effects on reproductive and skeletal health of physically active women Often compulsive eating disorders (or exercise) Intentional efforts to improve performance by reducing body weight and body fat Also inadvertant

Exericse doesn’t affect acute Ad-libitum energy intake Supresses relative energy intake Via known neuroendocrine mechanisms