Exercise Physiology APL2/L3
Our Body’s “gasoline” Adenosine Triphosphate Energy storing molecule “usable energy”
Energy Pathways (3) 1.ATP (6 sec): stored in mitochondria. 2. CP: Creatine phosphate (10 sec) A lot of it in muscles and builds ATP back up. (Creatine phosphate + ADP ↔ ATP + creatine) (Creatine phosphate + ADP ↔ ATP + creatine) 3. Glycogen: stored glucose in liver and muscles.(anaerobic) Fat: used last. Greatest potential energy source.
Cellular Respiration: Process which releases energy from organic compounds in cells. 3 reactions: glycolysis, citric acid cycle (Krebs), electron transport chain RESULT: CO2, H2O and energy. ½ IS HEAT, ½ IS USED TO MAKE ATP (ENERGY NEEDED BY MUSCLE CELLS)
Glycolysis: Breaking of glucose: 6-carbon glucose molecule →two 3-carbon pyruvic acid molecules. High energy electrons are delivered to ETC 2 molecules ATP produced
Krebs cycle Part II of Aerobic Respiration Charged Ions are produced and gotten ready for ETC. 2 ATP produced
Electron Transport Chain
ATP Between ETC and Krebs Cycle: 34 molecules of ATP are produced. A lot of heat is given off
Muscle fatigue and Oxygen Debt Normally, we breath enough O2 to support aerobic use of glucose. However… Strenuous use of muscles result in: anaerobic respiration: glucose is broken into pyruvic acid → lactic acid Lactic acid: not enough ATP to convert it to glucose at this time. Results in: O2 debt= muscle cramping/fatigue
Hypertrophy of Muscles Muscles forcefully exercised will enlarge There is ↑ in muscle fiber size, not number of muscles. i.e: body builder/weight -lifter, prof. athlete
Atrophy of Muscles Atrophy of Muscles Muscles not used will decrease in size This is called muscle atrophy i.e: spinal cord patients: very thin and frail
Quick Quiz (2 pts/bullet) What is gasoline for our body? What are the 3 energy pathways in the cell? What 3 reactions make up cellular respiration and what do they produce? When does anaerobic respiration occur? How do muscles enlarge? What is increased muscle mass called?