Lecture 8: Cardiovascular adaptations to exercise training

Question 1

Exercise training does not change static or Dynamic Lung Function

Answer 1

regular exercise training generally does not lead to significant changes in these static or dynamic lung function measurements. In other words, exercise training does not usually increase the total volume of the lungs or improve the speed of airflow during breathing.
=> while exercise greatly benefits the cardiovascular system, it doesn’t notably increase lung capacity or airflow speed.

This is because the actual capacity of the lungs to move air in and out (ventilation) is usually not a limiting factor in most people.
==> respiratory muscles generally do not reach their maximum capacity even during intense exercise.

Expcetion : Swimmers/Divers Due to Resistance Imparted by Water
swim or dive, the water creates resistance against your chest and lungs as you breathe
==> resistance can strengthen the respiratory muscles (like the diaphragm and intercostal muscles) because they have to work harder to overcome the pressure exerted by the water.
==> could include better respiratory muscle endurance, possibly leading to marginal increases in lung volumes or the efficiency of air movement during breathing
-> though these changes are generally not as pronounced as the cardiovascular adaptations seen with exercise.

Question 2

Exercise training HR and CO

Answer 2

After training, the heart doesn’t need to beat as often to deliver the same amount of blood to the body at rest. This results in a lower resting heart rate, which is often seen as a sign of good cardiovascular health.

Similarly, during exercise at submaximal intensities (less than maximum effort), the heart rate is lower after training.

===> heart’s stroke volume has increased due to cardiac hypertrophy, meaning it can pump more blood with each beat, reducing the need for a higher heart rate to meet the body’s demands for oxygen.

Max HR remains the same:
primarily determined by age and is not significantly altered by training
Even though your heart becomes more efficient, the maximum rate at which it can beat typically stays the same.
so HR is the same, but with training, less likely to reach it because you’re adapted

Despite no change in maximum heart rate, maximal cardiac output increases with training
cardiac hypertrophy = increased stroke volume// pump more blood per beat
-> A higher cardiac output means more oxygen can be delivered to the muscles, which enhances performance and endurance.

Question 3

Exercise training improves Neuromuscular Efficiency

Answer 3

Regular training improves the efficiency of neural connections that control muscle movements.
==> more coordinated and efficient muscle contractions
==> better performance and reduced energy expenditure for the same movements, delaying fatigue.

Question 4

Exercise training Delay in Fatigue Onset

Answer 4

better at utilizing fat as a fuel source, especially during prolonged exercise
=-> reduces the reliance on muscle glycogen (the stored form of glucose)
[glycogen depletion is closely associated with fatigue] == this “glycogen sparing” effect helps delay the onset of fatigue.

trained muscles produce less lactate at a given exercise intensity due to improved aerobic capacity,
[Lactate accumulation in the muscles is a key factor leading to fatigue]

Question 5

Exercuse training improves Oxygen Delivery and Utilizationce

Answer 5

causes increased cardiac output and higher hemoglobin levels
=> n more efficient delivery of oxygen to the working muscles
=> receive adequate oxygen even during intense exercise, which is crucial for sustained performance.

Training increases the number and efficiency of mitochondria in muscle cells
=> produce energy more efficiently, which delays the onset of fatigue.

Question 6

Exercise training improved Cardiovascular Efficiency

Answer 6

Exercise training, especially aerobic training, leads to cardiac hypertrophy, which is an increase in the size and strength of the heart muscle
- pump more blood per beat (increased stroke volume)
- higher cardiac output (CO)
- without requiring an increase in heart rate.

the heart becomes more efficient, so it doesn’t need to beat as fast to deliver the same amount of oxygen to the muscles during submaximal exercise
Low heart rate is an indication of improved cardiovascular fitness.

Question 7

glycogen depletion on muscle funtion and fatigue

Answer 7

• glycogen stores become depleted == muscles’ ability to produce ATP through glycolysis decreases
• muscles cannot sustain the same level of power output or endurance.
• the body shifts more heavily toward fat metabolism
  ==> it is metabolized more slowly than glycogen, meaning the rate of ATP production is reduced. This slower energy production contributes to a decline in exercise intensity.
  As glycogen stores diminish, the body begins to experience fatigue

Question 8

Reversibility Principle

Answer 8

All of these training-induced changes can be rapidly
reverse without constant training
* i.e. de-training
* Dose-dependent fashion
* Use it or lose it – reversibility principle

==> the adaptations resulting from exercise training can be rapidly reversed if training ceases—a concept known as de-training. Regular, consistent training is necessary to maintain these benefits and continue improving performance and delaying fatigue.