Outline catabolism.

Describe the aerobic production of ATP before electrons are passed into the electron transport chain.

Describe the replacement of glycogen stores during recovery from fatigue after a long-distance swim.

Analyse the long-term effect of training on maximal oxygen consumption.

Evaluate the implications of genetic screening in sport.

catabolism is the breakdown of complex molecules into simpler molecules, with the release of energy ✔

glycolysis / Krebs cycle occurs before the ETC ✔

glycolysis takes place in the muscle sarcoplasm ✔

glucose is broken down to pyruvic acid ✔

pyruvic acid enters the Krebs cycle <via conversion to acetyl-coA> in the presence of oxygen ✔

fatty acids are catabolized into acetyl-coA✔

acetyl-coA and oxaloacetic acid combine to form citric acid ✔

glycolysis: net 2 ATP resynthesized ✔

Krebs cycle takes place in the mitochondria <matrix> ✔

citric acid enters the Krebs cycle ✔

carbon dioxide is released ✔

hydrogen ions are released into the ETC ✔

Krebs cycle: 2 ATP resynthesized ✔
OR
net 4 ATP yield for glycolysis and Krebs cycle ✔

endurance training significantly reduces muscle/liver glycogen stores ✔

muscle glycogen recovery will be preferential over liver ✔

both muscle/liver glycogen can be replenished within 24 hours of activity ✔

to optimize on glycogen synthesis, carbohydrates should be eaten immediately and at frequent intervals <1.2 g per kg> ✔

optimal window within the first 2 hours ✔

5–12 g per kg of body weight will allow replenishment within 24 hours ✔

aerobic training is likely to cause a higher VO₂ max than those with no training ✔

anaerobic non-interval training is likely to have little effect on VO₂ max compared to those with no training
OR
high-intensity interval training produces improvements in maximum oxygen consumption ✔

activities where individuals have trained a greater area of muscle mass are likely to have a higher VO₂ max ✔

due to an increase in stroke volume/ maximal cardiac output ✔

increased oxygen carrying capacity/hemoglobin content ✔

increased capillary density in muscles ✔

increased mitochondrial density / arteriovenous difference ✔

increased maximal minute ventilation/increased muscular endurance of respiratory muscles ✔

Accept other appropriate physiological adaptations.

Award max [4] if only physiological adaptions given.

Strengths:
identify potential health conditions that may be life threatening, eg sudden cardiac death ✔

identify susceptibility to injury and so reduce its risk ✔

potentially use for talent identification ✔

Limitations:
possible exclusion from sport due to predetermined factors ✔

discrimination from future employment ✔

could support the development of gene doping ✔