energy systems, metabolism and nutrients

Question 1

explain ATP turnover

Answer 1

• energy stored in chemical bonds produce energy consuming work like muscle contraction - split off phosphate groups liberating energy leaving diphosphate - resynthesising ATP from ADP goes through different metabolic pathways

Question 2

what are the ATP requirements during exercise?

Answer 2

• success dependant on ability to provide energy and sustain contraction at correct intensity - ATP hydrolysis is at its highest when performing max sprint - ATP rate slower in low intensity and high duration as turnover needs to be sustained

Question 3

how does ATP resynthesise?

Answer 3

• through different energy systems as we only ave a small amount of ATP in our cells and it must be maintained - done through different energy systems

Question 4

what energy systems are in anaerobic metabolism?

Answer 4

1. phosphocreatine 2. glycolysis

Question 5

what energy systems are in aerobic metabolism?

Answer 5

1. glucose 2. palmitate

Question 6

explain the phosphocreatine system?

Answer 6

• used in skeletal muscle to resynethsise ATP - fastest way of regenerating ATP - Per, phosphate breaks off resulting in creatine + ATP - generates 1 ATP - PCr + ADP + H&raquo_space; Cr + ATP

Question 7

explain the glycolysis system?

Answer 7

• 2 ATP through anaerobic glycolysis of glucose -glucose + 2ADP +2Pi&raquo_space; 2 lactate + 2H2O + 2ATP -can also be down with glycogen, similar but produces 3 ATP due to it being the starting substrate

Question 8

explain the glucose system?

Answer 8

• feed products of glycolysis into mitochondria - 36 ATP - glucose+6O2+36ADP»6CO2+6H2O+36ATP

Question 9

explain the palmitate system?

Answer 9

• fat metabolism - fatty acid but occurs slower so intensity must be slow -130 ATP

Question 10

intramuscular stores

Answer 10

• very small

Question 11

how do you sustain contractions?

Answer 11

• ATP must be regenerated at a sufficient rate to sustain a strong level of contractility

Question 12

what system provides the fastest ATP generation and which the slowest?

Answer 12

1. fastest = PCr but produces smallest amount 2. aerobic slowest but most ATP

Question 13

how does exercise intensity affect different pathways?

Answer 13

• concentration of ATP in skeletal muscle doesn’t change because use of ATP is bathed with resynthesis - PCr stores decline in low intensities - as intensity increases producing lactate causing increased contribution from anaerobic glycolysis

Question 14

what happens to ATP during sprinting?

Answer 14

1. 6 seconds there’s slight contribution. largely PCr and some anaerobic glycolysis 2. duration continues so ATP production falls due to PCr decline 3. maintain power output due to contribution from aerobic pathways

Question 15

what happens to ATP during prolonged low intensity exercise?

Answer 15

1. few minute aerobic metabolism takes over 2. carb oxidation and fat oxidation 3. if sufficient carbs at beginning they can keep producing 4. running out - relying on fat

Question 16

what are the fuels for aerobic metabolism?

Answer 16

1. carbs 2. fats 3. protein 4. aerobic in mitochondria

Question 17

influence of exercise duration on the fuels?

Answer 17

• fall in glycogen utilisation so others must contribute -blood glucose runs out 2 hours in unless consuming

Question 18

influence of exercise intensity on fuels?

Answer 18

• at rest= plasma fatty acids and plasma glucose metabolising 70% fat - low intensity - contribution from other sources

Question 19

carb stores for a man

Answer 19

• blood glucose: 3-5g - liver glycogen: 80-100g - muscle glycogen: 300-400g

Question 20

fat stores

Answer 20

• adipose tissue 3.5-14kg - muscle trig 200-500g

Question 21

how does food help metabolism?

Answer 21

• food provides nutrients having physiological and biochemical functions in body - helps provide energy, reg of metabolism and promotion of growth and development

Question 22

what is the difference between macronutrients and micronutrients

Answer 22

• macronutrients = present in large amount of human diet (carb, fat, protein, water) - micro = vitamins, minerals

Question 23

how to carbs aid the body

Answer 23

• provide energy for CNS and PA - 60% energy intake - sugars (simple carbs), starches and fibres

Question 24

name the 3 types of carbs

Answer 24

1. monosaccharides (glucose, fructose) 2. disaccharides (maltose, sucrose) 3. complex (amylose, maltodextrin)

Question 25

how do fats aid the body?

Answer 25

• energy source protection of vital organs - precursors for bile, hormones and steroids - 30 % energy intake, palatability - fat soluble vitamin intake

Question 26

types of fats

Answer 26

• triglycerides - most abundant - fatty acids - short medium or long - saturated fatty acid - unsaturated fatty acid (one or more double bond)

Question 27

how do proteins aid the body?

Answer 27

• structure to cells, central role in metabolism of organs and tissues - amino acids precursors for body proteins synthesis - 10% energy intake

Question 28

how is the difference between complete and incomplete protein

Answer 28

1. complete = contains all 9 essential amino acids

Question 29

how does water aid the body

Answer 29

• 60% water, 2/3 cells, 1/3 of extracellular fluid

Question 30

function of water in body

Answer 30

• nutrient transport, protection, biochemical reactions, medium for reactions