Free Fatty Acids and Energy Metabolism Quiz

Endurance Training and Energy Production

• The primary source of energy during endurance training is carbohydrates.
• Phosphofructokinase (PFK) is the rate-limiting step in glycolysis.
• When pyruvate is converted to lactate, it occurs through the process of lactic acid fermentation.
• Endurance training leads to an increase in lactate dehydrogenase (LDH) 1 and 2 isoforms.

Cellular Energy Production

• The primary function of the Glycerol-phosphate shuttle in muscle cells is to regenerate NADH from FADH2.
• An increase in mitochondrial volume is an adaptation that occurs with endurance training.
• Intermyofibrillar mitochondria show greater adaptability to training.
• The primary function of myoglobin in muscle cells is to store oxygen.

ATP Production

• Pyruvate Dehydrogenase (PDH) is activated via PDH phosphatases when stimulated by insulin and NAD+.
• With an increase in VO2max, the O2 cost for any absolute workload decreases.
• The net ATP production from the complete oxidation of one molecule of palmitate-16 through Beta-Oxidation and the Krebs Cycle is 106 ATP.
• The primary function of the Electron Transport Chain (ETC) in ATP production is to generate ATP through the transfer of electrons.

Glucose Metabolism

• The formula for calculating total ATP production from 1 molecule of glucose-6 is 36-38 ATP.
• Glucose-6 is converted to pyruvate through glycolysis, producing 2 ATP and 2 NADH.

Cardiovascular Function

• The average stroke volume (SV) per beat is 70-80 mL.
• The formula for calculating stroke volume (SV) is SV = EDV - ESV.
• The primary factor influencing preload in the context of stroke volume is ventricular filling.
• The formula for calculating ejection fraction (EF) is EF = (SV / EDV) x 100%.

Regulation of Stroke Volume

• The primary function of the Frank-Starling Mechanism in the context of stroke volume is to regulate cardiac output by adjusting ventricular stretch.
• The primary factor influencing afterload in the context of stroke volume is systemic vascular resistance.
• During moderate-intensity (MOD) exercise, stroke volume increases.
• The primary consequence of thermoregulation on stroke volume is a decrease in SV due to increased blood flow to the skin.
• When transitioning from lying down to standing, the primary factor influencing preload is the decrease in venous return.
• The primary function of the respiratory pump in influencing preload is to increase venous return through the creation of negative pressure.
• The primary function of the muscle pump when transitioning from standing to running is to increase venous return through the contraction of skeletal muscles.