Cardiovascular, Respiratory, and Energy Systems in Exercise - Vocabulary Flashcards

A set of vocabulary flashcards covering cardiovascular/respiratory responses to exercise, energy systems, and macronutrient roles based on the lecture notes.

HR (Heart Rate)

The number of times the heart beats per minute; increases with exercise and then reaches a steady state; normal resting HR is approximately 50-60 bpm,

HRmax (Max Heart Rate)

Estimated maximum heart rate used to gauge exercise intensity; roughly 220 - \text{age} .

Stroke Volume (SV)

The amount of blood ejected from the left ventricle with each beat; rests around 60 mL (female) to 80 mL (male) and can rise to \sim 110-150 mL during activity.

Cardiac Output (CO)

Total amount of blood pumped by the heart per minute; CO = HR \times SV ; typical resting values: female \sim 4 L/min, male \sim 5 L/min.

Blood Pressure (BP) – Systolic

Pressure in the arteries during heart contraction; increases with activity (normal \sim 120 ).

Blood Pressure (BP) – Diastolic

Pressure in the arteries during heart relaxation; relatively unchanged during exercise (normal \sim 80 ).

Blood Redistribution

Vasodilation to working muscles and vasoconstriction to non-active areas; during maximal exercise up to 80-90\% of blood flow directed to muscles.

Ventilation

Flow of air into and out of the alveoli; training can decrease the ventilation required at a given workload due to more efficient gas exchange; it still increases during exercise and then steadies.

Oxygen Uptake (VO2 Max)

Maximum rate at which oxygen can be taken up and used during maximal exercise; increases with training due to better delivery and extraction.

Haemoglobin

Oxygen-carrying protein in blood; levels can increase with training as plasma volume and red blood cell count rise to improve oxygen transport.

Capillarisation

Increase in capillary density around the heart and working muscles; expands surface area for diffusion and improves oxygen delivery.

Oxygen Exchange

Gas exchange between alveoli and capillaries; enhanced by greater diffusion surface area from training.

ATP (Adenosine Triphosphate)

The energy currency of cells; stored briefly in muscles (about 2-3 seconds) and must be replenished during activity.

Creatine Phosphate (CP)

High-energy phosphate store used to rapidly resynthesize ATP; limited stores and quickly depleted.

ATP-CP System

Immediate, anaerobic energy system that uses CP to rapidly regenerate ATP; dominant 0-10 seconds of high-intensity effort; very fast but limited fuel.

Lactic Acid System (Anaerobic Glycolysis)

Short-term energy system that breaks down glycogen to glucose without oxygen, producing lactate; dominant 10-60 seconds; yields \sim 2-3 ATP per glucose and causes fatigue via H+ accumulation.

Lactate

By-product of anaerobic glycolysis; accumulation can contribute to muscle acidosis and fatigue.

Aerobic System

Energy system that uses oxygen to fully oxidize glucose and fats; produces CO2, H2O , and heat; yields about 36 ATP per glucose; primary for rest and submaximal exercise.

Glycogen

Stored carbohydrate in muscle and liver; major carbohydrate fuel for high-intensity exercise.

Carbohydrates (CHO) as Fuel

Primary energy source during moderate-to-high intensity; stored as glycogen and glucose; all CHO ultimately contribute to ATP.

Fats as Fuel

Major energy source during rest and low-to-moderate intensity; requires more oxygen; stored as fats and mobilized as fatty acids for energy.

Proteins as Fuel

Not a primary energy source; mainly for growth/repair; may contribute to ATP in extreme situations.

Glycaemic Index (GI)

Classification of carbohydrate-containing foods by their impact on blood glucose levels.

Glycogen Depletion (Fatigue Factor)

Fatigue is limited by depletion of glycogen stores in the liver and muscles during prolonged or intense exercise.

Energy System Continuum

All energy systems contribute to energy production; there is a predominant system depending on activity: ATP-CP ( 0-10 s), Lactic ( 10-60 s), and Aerobic ( >60 s).

Oxygen Debt / EPOC

Oxygen debt refers to the initial oxygen deficit at exercise onset; Excess Post-Exercise Oxygen Consumption (EPOC) is the elevated oxygen uptake after exercise to restore the body to resting conditions.

Cardiac Hypertrophy

Increase in size of the left ventricular muscle from training; contributes to higher stroke volume.

Resting Heart Rate (RHR) with Training

Resting heart rate tends to decrease as the heart becomes more efficient at delivering oxygen and nutrients.

Blood Volume (Haemoglobin & Plasma)

Total blood volume can increase with training due to expanded plasma volume and higher red blood cell count, improving oxygen transport.

Which heart chamber is responsible for ejecting blood with each beat (Stroke Volume)?

The left ventricle.

Explain the terms 'vasodilation' and 'vasoconstriction' in the context of blood flow.

Vasodilation is the widening of blood vessels, while vasoconstriction is their narrowing. These processes regulate blood flow to different body areas.

During maximal exercise, what proportion of blood flow is directed to working muscles?

Up to 80−90%

What are alveoli, and what is their role in respiration?

Alveoli are tiny air sacs in the lungs that serve as the primary site for gas exchange between air and blood.

How does consistent training influence the amount of ventilation required for a given workload?

Training can decrease the ventilation required at a given workload due to more efficient gas exchange.

Describe the training adaptation affecting Haemoglobin levels and total blood volume.

With training, Haemoglobin levels and total blood volume (including plasma volume and red blood cell count) can increase, enhancing oxygen transport.

What are the main contributing factors to fatigue in the Lactic Acid System?

Accumulation of H+ ions, which leads to muscle acidosis, and the resulting accumulation of lactate, disrupt muscle function.

List the primary end-products generated by the Aerobic Energy System.

CO2, H2O, and heat.

In what specific form are fats utilized as fuel for energy in the body?

They are mobilized and used as fatty acids.

Where are the body's main glycogen stores located?

In the liver and muscles.

What does the acronym EPOC stand for, and what is its physiological significance?

EPOC stands for Excess Post-Exercise Oxygen Consumption. Its significance is the elevated oxygen uptake post-exercise to restore the body to pre-exercise resting conditions.

Which specific part of the heart undergoes an increase in size due to cardiac hypertrophy from training?

The left ventricular muscle.

How does Heart Rate typically change during a sustained period of exercise?

It increases and then reaches a steady state.

What are the approximate resting Stroke Volume (SV) values for females and males?

Female: 60 mL, Male: 80 mL.

To what approximate range can Stroke Volume (SV) rise during physical activity?

∼110−150 mL.

What are the typical resting Cardiac Output (CO) values for females and males?

Female: approximately 44 L/min, Male: approximately 55 L/min.

What is considered a normal resting Systolic Blood Pressure (BP) value?

Approximately 120.

What is considered a normal resting Diastolic Blood Pressure (BP) value?

Approximately 80.

What is the primary mechanism of blood redistribution during exercise?

Vasodilation to working muscles and vasoconstriction to non-active areas.

Why can training decrease the ventilation needed for a specific workload?

Due to more efficient gas exchange in the trained state.

What are the two main reasons VO2 Max increases with training?

Better oxygen delivery to muscles and more efficient oxygen extraction by muscles.

What two blood components increase with training that lead to improved oxygen transport via Haemoglobin?

Plasma volume and red blood cell count.

How does Capillarisation primarily improve oxygen delivery?

By expanding the surface area available for diffusion.

How long can ATP be stored in the muscles for immediate use?

About 2−3 seconds.

What is continuously required for ATP during physical activity?

It must be constantly replenished.

What are the key characteristics regarding the availability and depletion rate of Creatine Phosphate (CP) stores?

CP stores are limited and quickly depleted.

What distinguishes the ATP-CP system in terms of speed and fuel availability?

It is very fast but has limited fuel stores.

Approximately how many ATP molecules are yielded per glucose molecule in the Lactic Acid System?

Around 2−3 ATP.

What are the primary by-products of the Aerobic System?

CO2, H2O, and heat.

Approximately how many ATP molecules are yielded per glucose molecule in the Aerobic System?

About 36 ATP.

What is a key difference in oxygen requirement for fat metabolism compared to carbohydrate metabolism?

Fat metabolism requires more oxygen.