Energy Systems

Energy Energy = “The ability to perform work” 3 Types of Energy: Chemical Energy (Food) is converted to… Kinetic Energy (Movement) or is stored as fat i.e…. Potential Energy (Stored).

Work Work = Force x Distance Usually equal to bodyweight If you run 1500m or 800m, which one are you doing more work in? Answer – 1500m because the distance is greater If 2 people run 1500m and one does it faster than the other, which is exerting more POWER? Answer – the faster one Power = Work performed per unit of time (watts)

Power Experiment Follow the instructions on the sheet to find out each individuals Power Output. What do our findings show? Think about the results in terms of:  weights of performers in relation to times achieved,  methods of climbing stairs (use of rails, one or more steps at a time),  does fastest mean most powerful? Why/why not?

Energy The way energy is released in the body is complicated so for the purposes of A Level P.E. we learn an overview – but it is still quite complicated!!!

Energy There is only one useable form of energy in the body – ATP (Adenosine Triphosphate) ATP provides energy in all living cells in the body, including muscle tissue All sources of energy, found in food we eat, have to be converted into ATP before the potential energy in them can be released.

ATP ATP – a high-energy phosphate made up of one molecule of adenosine and three molecules of phosphate A T P Adenosine Tri (Three) Phosphate A PPP The bonds that hold the compound together = a lot of potential energy

ATP When compounds are broken down (i.e. the bond between molecules are broken) energy is released. A PP P A PP P Energy A reaction that releases energy – EXOTHERMIC REACTION

ATP What causes compounds to breakdown? Answer – Enzymes The enzyme responsible for breaking down ATP = ATPase A PP P A PP P Energy

ATP ATPase causes ATP to be broken down into ADP + P (i.e.Adenosine Diphosphate and a free Phosphate) releasing stored energy. ATP ADP + P + energy As energy cannot be created or destroyed, what does the released energy become? Answer – converted to Heat and Kinetic Energy

ATP There is a limited supply of ATP in the body and once it runs out we need to resynthesise it to keep supplying energy. When a compound is built up (synthesised) energy is needed to restore the bonds between the molecules A reaction that needs energy – ENDOTHERMIC REACTION

ATP Resynthesis ATP resynthesis from ADP + P is an endothermic reaction A PP P A PP P Energy ADP + P + energy ATP

ATP Resynthesis Resynthesis of ATP is achieved in 3 ways in the human body: The Phosphocreatine System (ATP-PC) (or alactic system) The Lactic Acid System (or glycolysis) The Aerobic System

Energy Systems Each system supplies energy for particular demands and duration, allowing us to cope with a variety of situations. The ATP-PC and Lactic Acid systems are ANAEROBIC The Aerobic system is AEROBIC (hence its name!!)

Divide the sporting pictures into: - Those needing quick energy over a short time (Anaerobic). - Those needing slow energy over a long time (Aerobic). You MUST be able to justify why you have placed a sport where it is! TASK

Answers Aerobic Anaerobic

TASK Re-sort the pictures into a hierarchy. Place the pictures you think need the most energy over a long time at the top of their list Place the pictures needing the most energy over a short time at the top of the other list. You MUST be able to justify why you have placed a sport where it is!

Answers Aerobic Anaerobic