Food Fuels used for ATP resynthesis

Food glorious food ! Food is the basic source of energy Ingested and digested and then absorbed in various forms which can be used to re synthesise ATP

Energy Providers…. Carbohydrates Fats Proteins (Amino Acids) Stored in the body as Glycogen Fats Stored as Triglycerides, broken down to free fatty acids to give energy Proteins (Amino Acids) Need to be converted to glucose to give energy

Carbs.. One molecule of glucose can re synthesise up to 38 molecules of ATP In body as glycogen or glucose Glucose in blood used to supply brain and nervous system Glucose stored in liver and muscle used for energy

Carbs.. Body can only store 80g of glycogen in liver 15g of glycogen per kilogram of muscle tissue Enough energy for a 10 mile run

Carbs.. To maximise glycogen stores athletes go through glycogen loading or Carbo loading..

Carbo Loading Dietary manipulation 6 days before event performer eats diet of high protein and fat- lots of exercise to burn off excess carbs. 3 days before event diet of high carbs and light exercise

Fats… Most abundant source of energy is stored as fat Triglycerides Before we can use fat it needs to be converted to Free Fatty Acids (FFA) This is very SLOW and needs lots of O2

Breakdown of a fat molecule.. The FFA’s must go through process called Beta Oxidation before its allowed to enter Krebs cycle. Once here it follows same path as glycogen metabolism.

Fats… In an endurance event body needs to use mix fat and carbs. Start- glycogen FFA’s preferred source for rest of event The better the body is at activating FFA’s the better performance as they will have glycogen stores left to finish the race

Fats… Can not use fat alone as it has rubbish solubility Hydrophobic Need to use glycogen sparingly to avoid ‘hitting the wall’ All glycogen gone- trying to use fat alone.

Hitting the wall…. Fat is not soluble and so cant be transported very well in the blood When the fats get to the mitochondria it takes too long and its in too small a quality to help with muscle contraction. Always used with glucose.

Hypoglycaemia Happens when stored liver glycogen is depleted and blood glucose levels can not be maintained. Usually in endurance events Sugary drinks the cure!

Effects of Training The more you train the more you rely on FFA’s for ATP production Due to increase in mitochondria

Protein Mainly used when glycogen supplies are low 5-10% of total energy Normally used for growth and repair Constant use of this for energy will affect muscle adaptation/ development

Recap.. Carbs & fats the main energy providers Intensity and duration plays a key role in which one is used more Breakdown of FFA needs more oxygen than glucose, so in high intensity activity where oxygen is short, glycogen is preferred We only have little stores of glycogen and need to conserve these