Responding to exercise
What increases during exercise?
1) Heart rate 2) Breathing rate 3) Breath volume
Explain why the breathing rate and breath volume increase during exercise.
A greater breathing rate means that air is inhaled and exhaled more frequently, and a greater breath volume means that more air is moved in and out each time. The rate of respiration increases during exercise, and these changes allow oxygen to be taken into the body faster and waste carbon dioxide to be released faster.
What happens when not enough oxygen is supplied to the respiring muscle cells?
Anaerobic respiration occurs in muscles: 1) Glucose undergoes incomplete oxidation 2) Lactic acid builds up in muscles 3) The muscles become fatigued and stop contracting efficiently.
What does a greater heart rate mean?
Blood is pumped faster around the body. It can transport oxygen and glucose to cells faster, and remove carbon dioxide faster.
Where does blood transport lactic acid to and from?
From the muscles to the liver, where it is converted back into glucose.
What happens to oxygen during exercise?
Insufficient (not enough) oxygen may be supplied to the respiring muscles for anaerobic respiration.
How is heart rate calculated?
Measured by counting the pulse rate in the wrist. It is usually counted during periods of 15s, then multiplied by 4 to get beats per minute.
How is resting breathing rate counted?
Over periods of one minute. During exercise, and after it, shorter periods of 15s or 30s may be better.
What do your muscles need more of when you exercise?
Oxygen and glucose, and release more carbon dioxide.
What does the human body do during exercise?
Reacts to the increased demand for energy
What is oxygen debt?
The amount of extra oxygen the body needs after exercise to react with the accumulated (saved) lactic acid and remove it from the cells. This is why, for a while after exercise, you still breath heavily and your heart continues to beat faster than normal.
What happens to your muscle cells when you exercise?
They respire faster
How is breath volume measured?
Using a device called a spirometer