energy systems

• • most commonly used source of ATP when starting physical activity as it provides up to 10 seconds of energy for explosive, high intensity actions
  • relies on another chemical compound found in the muscles (CP).
  • breakdown of CP provides enough energy to recombine ADP + P into ATP and can be recombined just as quickly as it is broken down.
  • ATP can break down into ADP + P and release energy for muscle contraction.
  • limited supplies of CP, the ATP-CP system can only provide up to 10 more seconds of energy before the stores are exhausted.
  • works almost entirely without waste products.
• • after carbs have been broken down into glycogen, reconverted into glucose by enzymes to release energy for ATP recombination
  • working muscles need ATP at a faster rate than can be provided by complete breakdown of glucose.
  • pyruvic acid created by anaerobic glycolysis cannot be processed by oxygen > converted to lactic acid.
  • lactate + hydrogen ions accumulate -> muscular contractions are restricted
  • body tolerates levels of lactate + hydrogen ions until accumulation rate is greater than body's ability to remove
  • lactate threshold is created -> must stop/reduce activity
• • oxygen is increased + used for complete breakdown of muscle fuel sources (their breakdown releases energy for ATP recombination)
  • carbohydrates, stored in the muscles as glycogen, are broken down to glucose through glycolysis
  • breakdown of fuel sources with the use of oxygen requires more energy and takes longer, requiring a drop in the intensity of the activity.
  • body starts the burn fats (triglycerides) then proteins (amino acids) found in the muscles to break them down and create energy
  • releases waste products in the form of carbon dioxide and heat.
• Adenosine Triphosphate (ATP) is a chemical compound stored in the muscles that can be broken down into Adenosine Diphosphate (ADP). The breakdown creates a release of energy used to lengthen or shorten the muscles for movement.
• • energy systems work together by overlapping rather than switching off as another system takes over
  • first 10 seconds of physical activity, the main source of ATP is the ATP-CP system
  • at around 15-20 seconds, the lactic acid system begins to take over
  • lactic acid system peaks in performance between 30-60 seconds into exercise
  • after about 2 minutes of activity, the oxygen supply to muscles has increased enough for the aerobic system to take over
  • after five minutes of activity, the aerobic system is producing the majority of the energy and continues to until exercise stops