Exercise and Metabolism: Human Physiology Practice Flashcards

A set of vocabulary flashcards based on the Year 1 Human Physiology lecture notes covering energy systems (ATP-PCr, Glycolysis, Aerobic), muscle structure, and performance-enhancing strategies like creatine and bicarbonate supplementation.

Adenosine Triphosphate (ATP)

The universal energy currency that stores potential energy from food within its chemical bonds to power biological work.

Phosphocreatine (PCr)

The energy reservoir in cells that recycles ATP for further muscle contractions and powers very high-intensity exercise for approximately 10-15 seconds.

Glycolysis

Also known as the Embden-Mayerhof pathway, this process consists of 10 enzymatic reactions in the cytoplasm that convert a 6-carbon glucose molecule into two 3-carbon pyruvate molecules.

Citric Acid Cycle

A series of reactions occurring in the matrix of the mitochondria where the acetyl portion of Acetyl-CoA joins with oxaloacetate to form citrate, eventually producing ATP and hydrogen carriers.

Electron Transport Chain

The metabolic pathway that produces between 30-34 ATP per molecule of glucose through the use of $NADH$ and $FADH_2$ in the inner mitochondrial membrane.

VO2max

The maximal rate of oxygen consumption, which represents the limit for aerobic metabolism and serves as a measure of cardiorespiratory fitness.

Creatine Kinase

The enzyme responsible for catalyzing the reaction where phosphocreatine (PCr) converts ADP back into ATP.

Anaerobic Metabolism

Energy pathways, such as the phosphagen system and glycolysis, which can occur in the absence of oxygen.

Aerobic Metabolism

Energy pathways that can only occur in the presence of oxygen, specifically the Citric Acid Cycle and the Electron Transport Chain.

Bicarbonate (NaHCO3) Supplementation

The ingestion of approximately $0.3\,g$ per kg body mass to increase extracellular pH and allow $H^+$ ions to exit muscle cells faster, potentially improving middle-distance performance.

Carbohydrate Loading

A strategy involving diet and exercise used to maximize pre-exercise muscle glycogen content to delay depletion during endurance events.

Creatine Monohydrate Supplementation

The use of capsules or powder to increase muscle creatine stores by up to 30% for improved ATP re-synthesis and PCr depletion delay during sprinting.

Myosin

The thick filaments within muscle fibrils that attach to thin filaments to pull them inward during contraction.

Actin

The thin filaments within muscle fibrils that are pulled by myosin cross-bridges during muscle contraction.

Lactate Dehydrogenase

The enzyme that catalyzes the binding of hydrogen to pyruvate to form lactate during high-intensity or anaerobic exercise.

Pyruvate Dehydrogenase

The enzyme responsible for converting pyruvate into Acetyl-CoA to enter the Citric Acid Cycle.

Citrate Synthase

The enzyme that catalyzes the reaction joining the acetyl portion of Acetyl-CoA with oxaloacetate to form citrate.

Acidosis

An increase in intracellular or extracellular acidification (a drop in pH) often associated with the accumulation of $H^+$ ions during intensive exercise.

ATP Re-synthesis Rate

The speed at which ATP is regenerated, measured in $mmol\,ATP\,kg^{-1}\,dm^{-1}\,s^{-1}$, which determines which energy system fuels specific forms of exercise.

Formative Assessment

Assessments such as online quizzes used for on-going learning to help students identify content they find easy or hard.

Summative Assessment

Evaluative tasks used to determine grades, such as the 1750-word coursework report or the 40-question multiple choice examinations.