Respiratory Processes & Exercise Physiology: Key Concepts and Training Principles

What are the four respiratory processes?

Pulmonary ventilation, pulmonary diffusion, transport of gases via blood, capillary diffusion (internal respiration)

What is pulmonary ventilation?

Movement of air into and out of the lungs.

Which muscles are primarily responsible for inspiration?

Diaphragm and external intercostals.

What happens to thoracic volume during inspiration?

It increases.

What happens to intrapulmonary pressure during inspiration?

It decreases below atmospheric pressure.

Why does air enter the lungs during inspiration?

Air moves from high pressure to lower pressure.

Is expiration normally active or passive?

Passive.

Which muscles are used during forced expiration?

Internal intercostals and abdominal muscles.

What is the respiratory pump?

Pressure changes during breathing that help return venous blood to the heart.

Approximately what percentage of resting VO₂ is used for breathing at rest?

<5%.

During intense exercise, breathing may require up to what percentage of VO₂?

About 30%.

What instrument measures lung volumes?

Spirometer (spirometry).

What is tidal volume?

Amount of air inhaled or exhaled during a normal breath.

What is vital capacity (VC)?

Maximum amount of air exhaled after a maximal inspiration.

What is residual volume (RV)?

Air remaining after maximal expiration.

What is total lung capacity (TLC)?

Vital capacity + residual volume.

What is atmospheric pressure at sea level?

760 mmHg.

What percentage of atmospheric air is oxygen?

About 20.93%.

What percentage of atmospheric air is nitrogen?

About 79%.

According to Dalton's Law, total atmospheric pressure equals what?

The sum of the partial pressures of all gases.

What drives diffusion of oxygen and carbon dioxide?

Partial pressure gradients.

How is most oxygen transported in blood?

Bound to hemoglobin.

Approximately what percentage of oxygen is dissolved in plasma?

Less than 2%.

What is oxyhemoglobin?

Hemoglobin bound to oxygen.

What is deoxyhemoglobin?

Hemoglobin not bound to oxygen.

One gram of hemoglobin can carry approximately how much oxygen?

1.34 mL O₂.

What determines the oxygen-carrying capacity of blood?

Hemoglobin concentration.

What condition decreases oxygen-carrying capacity because of reduced hemoglobin?

Anemia.

What are the three forms of CO₂ transport?

Bicarbonate ions, carbaminohemoglobin, dissolved in plasma.

Which form transports the greatest percentage of CO₂?

Bicarbonate (60-70%).

Approximately what percentage of CO₂ is transported as carbaminohemoglobin?

About 20-33%.

Approximately what percentage of CO₂ is dissolved in plasma?

About 7-10%.

What does the arterial-venous (a-v) O₂ difference represent?

The amount of oxygen extracted by tissues.

During heavy exercise, what happens to the (a-v) O₂ difference?

It increases.

Which muscle protein stores and transports oxygen within muscle fibers?

Myoglobin.

Compared with hemoglobin, does myoglobin have a higher or lower affinity for oxygen?

Higher affinity.

What three blood variables are tightly regulated by ventilation?

PO₂, PCO₂, pH.

Which change is the strongest stimulus for increased ventilation?

Increased CO₂ (and increased H⁺/decreased pH).

Where are central respiratory centers located?

Medulla oblongata and pons.

Where are peripheral chemoreceptors located?

Carotid bodies and aortic bodies.

What information do peripheral chemoreceptors detect?

Blood PO₂, PCO₂, and H⁺.

What is muscular strength?

The maximal force a muscle or muscle group can generate (often measured by 1 RM).

What is muscular power?

The rate of doing work.

What is the equation for power?

Power = Force × Distance ÷ Time.

What is muscular endurance?

The ability to sustain repeated muscle contractions or maintain a static contraction.

What does the principle of individuality state?

Training programs should be tailored to the individual's needs and abilities.

What does the principle of specificity state?

Adaptations are specific to the type of training performed.

What does the principle of reversibility state?

Training gains are lost when training stops.

What does the principle of progressive overload state?

Training stress must gradually increase as the body adapts.

What does the principle of periodization state?

Training should systematically vary intensity, volume, and specificity over time.

What should be included in a resistance training needs analysis?

Goal assessment, muscle groups to train, type of training, energy systems to train, injury-prevention concerns.

What training variables should be decided when designing a resistance program?

Exercises, exercise order, sets, repetitions, intensity, rest periods, movement speed.

Recommended rest between sets for muscular endurance?

20-30 seconds.

Recommended rest between sets for hypertrophy?

30-90 seconds.

Recommended rest between sets for maximal strength?

2-3 minutes.

In what order should muscle groups generally be trained?

Large muscles before small muscles.

Which exercises should generally come first?

Multi-joint (core) exercises.

Should multi-joint or single-joint exercises come first?

Multi-joint.

Why are core lifts generally performed before auxiliary lifts?

They require more energy, coordination, and multiple muscle groups.

What is a macrocycle?

The overall long-term training cycle.

What is a mesocycle?

A medium-length phase within a macrocycle.

What is a microcycle?

The shortest training cycle (usually about a week).

What are the four phases of periodization?

Preparation, pre-competition, competition, active rest.

What is hypertrophy?

Increase in muscle fiber size.

What is hyperplasia?

Increase in the number of muscle fibers (limited evidence in humans).

Which muscle fiber conversion commonly occurs with training?

Type IIx → Type IIa.

What are the major neural adaptations to strength training?

Increased motor unit recruitment, altered motor neuron firing rates, enhanced motor unit synchronization, reduced neural inhibition.

What is progressive resistance exercise?

Gradually increasing resistance as muscles adapt.

Why is progressive overload necessary?

To continue stimulating strength gains.

Recommended repetition range for strength?

4-12 RM.

Strength gains generally decrease when repetitions exceed what number?

About 15 repetitions.

How many sets are recommended for highly trained athletes?

4-8 sets per muscle group.

How many sets are recommended for trained non-athletes?

3-8 sets.

How many sets are recommended for untrained individuals?

1-4 sets.

What is the recommended resistance-training frequency?

About 3 days per week.

Do free weights and machines produce similar strength gains?

Yes, overall.

What is one advantage of free weights?

Greater movement specificity and stabilization.

What is one disadvantage of free weights?

Greater injury risk if technique is poor.

Do males and females gain strength similarly with short-term training?

Yes.

Why do men generally show greater long-term hypertrophy?

Higher testosterone levels.

What is undertraining?

Training below the level needed to improve performance.

What is acute overload?

Training stress sufficient to stimulate adaptation.

What is overreaching?

Short-term heavy overload followed by recovery and improved performance.

What is overtraining?

Chronic excessive training causing prolonged performance decline.

What two training variables can become excessive?

Volume and intensity.

As training intensity increases, what should happen to training volume?

It should generally decrease.

Can a few days of rest usually fix overtraining syndrome?

No.

What is one common sign of overtraining?

Declining performance.

What are other common symptoms of overtraining?

Chronic fatigue, sleep disturbances, irritability, loss of motivation, poor concentration, appetite changes.

What is one practical way to monitor for overtraining?

Heart rate response to a standard exercise bout.

What is considered the easiest practical indicator of early overtraining?

Changes in heart rate during standardized exercise.

What is the primary treatment for overtraining?

Markedly reduce training or rest completely.

What is the best prevention strategy for overtraining?

Proper periodization.

Why is adequate carbohydrate intake important during heavy endurance training?

It helps maintain glycogen stores and reduce overtraining risk.

What is tapering?

Reducing training volume and intensity before competition.

Why does tapering improve performance?

It allows recovery while maintaining fitness.

Does tapering reduce VO₂max?

No.

What is the average performance improvement with proper tapering?

About 3%.

What is detraining?

Loss of training adaptations due to reduced or stopped training.

What happens to muscular strength during detraining?

It decreases.