Unit 13: Cardiovascular System
Identify the component of blood responsible for transporting oxygen.
Erythrocytes (red blood cells)
Identify the structure where gas exchange occurs in the lungs.
Alveoli
Identify the division of the nervous system that acts as the control center of the body.
Central Nervous System (CNS)
Define the principle of specificity.
Training must be matched to the specific demands of the sport or goal
Identify the hormone that regulates red blood cell production.
Erythropoietin (EPO)
Describe two functions of blood in the human body.
Transports gases, nutrients, and waste products
Regulates body temperature and pH
Describe two functions of the respiratory system.
Gas exchange (oxygen intake and carbon dioxide removal)
Regulation of blood pH by controlling carbon dioxide levels
Describe two functions of the nervous system.
Detects internal and external stimuli (sensory function)
Initiates responses through muscles or glands (motor function)
Describe two variables that can be adjusted to apply progressive overload.
Intensity (e.g., increasing weight or speed)
Duration or frequency of training sessions
Describe two ways the body maintains homeostasis during exercise.
Adjusts heart rate and breathing rate
Regulates body temperature through blood flow and sweating
Explain how oxygen is transported from the lungs to working muscles.
Oxygen enters the blood in the lungs where partial pressure is high
Oxygen binds to hemoglobin in red blood cells
At muscles, where oxygen pressure is low, oxygen dissociates from hemoglobin and diffuses into tissues
Explain how the diaphragm contributes to inhalation.
The diaphragm contracts and flattens
This increases the volume of the thoracic cavity
Increased volume lowers pressure in the lungs, causing air to move in
Explain the difference between the sympathetic and parasympathetic nervous systems.
The sympathetic nervous system activates the “fight or flight” response
It increases heart rate and prepares the body for activity
The parasympathetic nervous system promotes “rest and digest,” slowing heart rate and conserving energy
Explain the principle of reversibility.
Training adaptations are lost when training stops or is reduced
The body returns toward its original fitness level
This loss occurs faster than the rate of adaptation
Explain how the respiratory and cardiovascular systems work together during exercise.
The respiratory system increases oxygen intake and removes carbon dioxide
The cardiovascular system transports oxygen to muscles via the blood
Together, they ensure muscles receive oxygen for aerobic respiration
Explain the differences in structure and function between arteries and veins.
Arteries have thick, muscular walls to withstand high pressure and carry blood away from the heart
Veins have thinner walls and valves to prevent backflow and return blood to the heart
Arteries transport blood under high pressure, while veins operate under low pressure
Veins rely on valves and muscle contractions to assist blood flow
Explain how structural features of the alveoli make gas exchange efficient.
Alveoli have thin walls, allowing rapid diffusion of gases
They have a large surface area, increasing the rate of gas exchange
They are surrounded by capillaries, maintaining a diffusion gradient
Moist surfaces allow gases to dissolve and diffuse efficiently
Explain the roles of proprioceptors, chemoreceptors, and baroreceptors in maintaining homeostasis.
Proprioceptors detect body position and movement
Chemoreceptors detect changes in blood chemistry such as oxygen and carbon dioxide levels
Baroreceptors monitor blood pressure
Together, they send information to the CNS to regulate body functions and maintain stable internal conditions
Explain how recovery contributes to improved performance in a training program.
Recovery allows the body to repair damaged tissues
It enables physiological adaptation to training stress
Prevents overtraining and reduces risk of injury
Adequate recovery improves overall performance and consistency
Explain how the nervous system regulates heart rate during exercise.
Sensory receptors detect increased activity and changes in the body
The CNS processes this information
The sympathetic nervous system increases heart rate
This allows greater oxygen delivery to working muscles
Analyze how an increase in red blood cell count (e.g., through altitude training or blood doping) can improve athletic performance.
Increased red blood cells raise hemoglobin levels
More hemoglobin allows greater oxygen transport capacity
Increased oxygen delivery enhances aerobic respiration
This leads to greater ATP production for endurance performance
As a result, athletes can sustain higher intensity exercise for longer periods
Analyze how ventilation increases during exercise and how this supports performance.
Exercise increases carbon dioxide production and oxygen demand
Chemoreceptors detect increased CO₂ levels and stimulate breathing rate
Ventilation rate and depth both increase
More oxygen is delivered to the blood and transported to muscles
Increased oxygen availability enhances aerobic respiration and ATP production, improving performance
Analyze how the nervous system helps regulate physiological responses during exercise.
Sensory receptors detect changes such as increased CO₂ levels and muscle activity
The CNS processes this information and coordinates a response
The sympathetic nervous system increases heart rate and breathing rate
Motor signals are sent to muscles to sustain contraction and movement
This coordination ensures the body meets increased energy demands during exercise
Analyze how the principles of specificity and progressive overload can be applied to improve athletic performance.
Specificity ensures training targets the relevant muscles, skills, and energy systems
This leads to sport-specific adaptations
Progressive overload gradually increases training demands
This prevents plateaus and promotes continuous improvement
Together, they optimize performance by ensuring targeted and ongoing adaptation
Analyze how altitude training improves endurance performance using multiple body systems.
Lower oxygen levels stimulate increased EPO production
This increases red blood cell count and oxygen-carrying capacity
The respiratory system adapts to improve oxygen uptake
The cardiovascular system transports more oxygen to muscles
These adaptations improve aerobic performance and endurance