L1. Physiology of training Flashcards
What is VO2max?
It is the maximum rate of oxygen consumption measured during incremental exercise
What physiological factors determine VO2max?
Cardiac output, oxygen delivery, and oxygen extraction by tissues
How is cardiac output calculated?
Cardiac output = Stroke Volume x Heart Rate
What does the Fick equation represent in exercise physiology?
It quantifies the relationship between oxygen consumption, cardiac output, and arterial-venous oxygen difference
What are the central and peripheral factors limiting exercise performance?
Central: Cardiac output and pulmonary diffusion. Peripheral: Muscle oxygen extraction and mitochondrial function
Why is the heart a key focus for exercise training?
It directly impacts cardiac output, stroke volume, and oxygen delivery to tissues
What experiment demonstrated the role of the pericardium in exercise performance?
Pigs with pericardiectomy showed a 30% increase in VO2max compared to sham-operated controls
How do oxygen levels affect exercise capacity in highly trained athletes?
Supplemental oxygen enhances performance in highly trained athletes due to improved pulmonary diffusion
What is the role of hemoglobin in exercise physiology?
Hemoglobin carries oxygen in the blood, and higher hemoglobin levels improve oxygen delivery and exercise performance
What was the significance of the blood transfusion experiment in runners?
It demonstrated that increasing hematocrit through transfusion enhances endurance performance
How does altitude training influence exercise performance?
Exposure to low oxygen pressure stimulates erythropoiesis, improving oxygen delivery capacity
What does the term ‘athlete’s heart’ describe?
An enlarged heart with greater stroke volume and reduced resting heart rate in trained athletes
What adaptation occurs in muscles during endurance training?
Increased mitochondrial density and oxidative capacity
How does lactate threshold differ between trained and untrained individuals?
Trained individuals have a higher lactate threshold, allowing prolonged high-intensity exercise
What is anaerobic threshold?
The point at which lactate starts accumulating in the blood during exercise
How does aerobic exercise differ from anaerobic exercise?
Aerobic exercise relies on oxygen metabolism, while anaerobic exercise relies on glycolysis
What is the significance of PGC-1α in exercise adaptation?
It is a master regulator of mitochondrial biogenesis and metabolic adaptation to exercise
What metabolic pathway is predominantly used in high-intensity anaerobic exercise?
Glycolysis, leading to lactate production
What experiment showed the muscle’s capacity for oxygen extraction?
One-legged exercise experiments demonstrated higher oxygen extraction compared to two-legged exercise
What physiological changes are observed in high-altitude adaptations?
Increased red blood cell count and improved oxygen carrying capacity
What are the metabolic benefits of prolonged exercise?
Improved fatty acid oxidation and increased efficiency in ATP production
How does type 2 diabetes affect exercise physiology?
It impairs glucose metabolism and reduces exercise efficiency
What is the role of the TCA cycle in exercise metabolism?
It produces ATP through oxidative metabolism in mitochondria
What device is commonly used to measure VO2max?
A cardiopulmonary exercise test (CPET) system
What was observed in Paula Radcliffe’s training data?
Her VO2max remained stable, but her lactate threshold improved significantly over time
What is the difference between VO2max and VO2peak?
VO2max is the plateau of oxygen consumption, while VO2peak is the highest observed value during a test
Why is resting bradycardia observed in athletes?
Due to increased stroke volume and cardiac efficiency
What experiment involved grayhounds and exercise performance?
Grayhounds with pericardiectomy showed improved performance due to enhanced cardiac filling
What is the oxygen cascade in exercise physiology?
The sequential drop in oxygen levels from the lungs to mitochondria
How does pulmonary fibrosis affect exercise capacity?
It reduces oxygen diffusion, limiting aerobic performance
What is the significance of diffusion limitation in trained athletes?
High cardiac output reduces time for oxygen diffusion in the lungs
What is cardiopulmonary exercise testing (CPET)?
A method to assess VO2max, ventilation, and other exercise parameters
What did experiments on red blood cell transfusions reveal?
Increased hematocrit improves VO2max and endurance
How does oxidative metabolism differ in trained muscles?
Trained muscles have greater mitochondrial density and ATP production capacity
What limits anaerobic exercise performance?
Accumulation of lactate and depletion of phosphocreatine
Why is mitochondrial biogenesis important for endurance?
It enhances the muscle’s ability to produce ATP and sustain prolonged activity
What are the central adaptations to aerobic training?
Increased cardiac output, stroke volume, and capillary density
What are peripheral adaptations to anaerobic training?
Increased muscle fiber recruitment, glycolytic capacity, and lactate tolerance
What experiment used supplementary oxygen during exercise?
Studies showed minimal effect in untrained but improvement in highly trained athletes
What is the role of hemoglobin concentration in exercise?
Higher hemoglobin improves oxygen transport and endurance performance
