Adaptations in Energy Systems and Enzymes

Adaptations in Energy Systems and Enzymes with Training

• The intensity of the workout affects the adaptations in the energy systems and enzymes.
• Sprint training leads to a faster rate of ATP hydrolysis and increased activity of ATPases and ATP regeneration enzymes.
• Sprinters have higher levels of ATP and total creatine compared to endurance athletes.
• Aerobic system does not respond well to 5-second sprints, but the glycolytic system shows a massive increase in sprint training.
• Carbohydrates are the primary fuel source at high power output, while fats are utilized more at lower intensities.
• With training, the transport of glucose into cells is increased through the stimulation of GLUT-4 by insulin or exercise.
• Trained individuals have higher glycogen levels, which allows them to exercise at higher intensities or for longer durations.
• Trained individuals are better able to utilize lactate as fuel.
• Protein has little involvement in energy production, but there is increased alanine production in the liver for gluconeogenesis.
• Enzymes involved in glycogen metabolism and glycolysis show adaptations with training, such as increased activity of glycogen phosphorylase and LDH.
• Training increases mitochondrial volume, enzyme activity, and myoglobin concentration, enhancing the capacity for oxidative phosphorylation and oxygen transport.
• ATP production remains the same from fuels, but there is an increased storage of ATP and PCr, resulting in less depletion of PCr during exercise.