BIOD43H3 Lecture Notes - Lecture 22: Excess Post-Exercise Oxygen Consumption, Cardiac Output, Motor Unit
BIOD43- Lecture 22: Physical Training
1. Circulation and Exercise
Blood flow back to the heart occurs through cycles of muscle contraction
• Isotonic exercises occur when muscle is contracting and relaxing over and over again,
like when running. Isotonic exercise results in increased cardio output and increased
blood pressure, due to blood flowing through one-way valve.
• Isometric exercises when someone is sustaining muscle contraction without subsequent
relaxation of muscle, there is large increase in Total Peripheral Resistance (TPR)
*TPR= the opposition to flow that blood encounters in vessels away from the heart
-No relaxation means that blood flow can not continue through. This in turn increases
blood pressure, however the central cardiac output has little change.
• Telecost bony fish have 2-chambered heart.
-Greater pressure at front of fish than the end (fins)
-Direction of blood flow flows from head to tail
-These fish have accessory heart to help pump blood back to head
• Ventilatory Control System
-Running increases rate of breathing to offset the lose of oxygen due to increased
carbon dioxide concentration
-CO2 increases, as pH and O2 decrease= increases ventilation drive
-Fish and amphibians under go ram ventilation and buccal oscillations (respectively)
1) Buccal cavity expands and air flows through the nose into bottom of mouth
2) Glottis opens; air flows from lungs and out of nostrils
3) Floor of mouth is raised; buccal cavity is compressed; air gets pumped into lungs
and glottis closes
• Lizards run with axial ventilation; where their spines move back and forth.
• Lizards= Increase ventilation with increased speed
=Increase oxygen consumption
=Limbs are below animal (not off to side)
• Iguana= Ventilation rate is greater during recovery (when animal stops and rests)
=No increase in ventilation with increased speed
=Experiences oxygen debt
=Axial ventilation impedes on its ability to ventilate with increased speed
=Limbs are more off to the side
Endurance Training Effects
• High motor unit activation frequency
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Document Summary
Biod43- lecture 22: physical training: circulation and exercise. Blood flow back to the heart occurs through cycles of muscle contraction. Isotonic exercises occur when muscle is contracting and relaxing over and over again, like when running. Isotonic exercise results in increased cardio output and increased blood pressure, due to blood flowing through one-way valve. Isometric exercises when someone is sustaining muscle contraction without subsequent relaxation of muscle, there is large increase in total peripheral resistance (tpr) *tpr= the opposition to flow that blood encounters in vessels away from the heart. No relaxation means that blood flow can not continue through. This in turn increases blood pressure, however the central cardiac output has little change: telecost bony fish have 2-chambered heart. Greater pressure at front of fish than the end (fins) Direction of blood flow flows from head to tail. These fish have accessory heart to help pump blood back to head: ventilatory control system.
