test 2

Most Likely Test Terms

Know these definitions word-for-word-ish:

1. Anaerobic training — high-intensity, intermittent exercise.

2. Motor unit — motor neuron + all muscle fibers it innervates.

3. Henneman's Size Principle — motor units are recruited from smaller to larger.

4. Hypertrophy — increase in muscle size/CSA.

5. Hyperplasia — increase in number of muscle fibers.

6. Cross-education — training one limb produces an effect in the opposite untrained limb.

7. Bilateral deficit — bilateral force is less than the combined unilateral force.

8. Bilateral facilitation — bilateral force is greater than the combined unilateral force.

9. Bone mineral density — amount of mineral in a given area of bone.

10. Wolff's Law — bone adapts to mechanical loading.

11. Overreaching — short-term excessive training that decreases performance.

12. Overtraining — excessive training over an extended period causing fatigue, illness, injury, and decreased performance.

13. Overtraining syndrome — prolonged maladaptation from excessive training/inadequate recovery.

14. Detraining — loss of adaptations due to stopping or substantially reducing training.

15. Retraining — adaptations returning after training resumes.

⭐ One thing to memorize above everything else:

ANAEROBIC TRAINING → NEURAL + MUSCLE + BONE + CONNECTIVE TISSUE + CV ADAPTATIONS → MORE STRENGTH, POWER & PERFORMANCE

OVERTRAINING → SYMPATHETIC FIRST → PARASYMPATHETIC LATER


1. What is Anaerobic Training?

Anaerobic training = high-intensity exercise performed in short or intermittent bouts.

Examples:

• Resistance/weight training

• Plyometrics

• Sprinting

• Speed and agility training

• HIIT

Energy systems

Remember: Anaerobic = high intensity + short duration.

2. Nervous System Adaptations ⭐

The nervous system is one of the first systems to adapt to anaerobic training.

This is why beginners can become stronger before their muscles actually get much bigger.

Main adaptations

A. Increased motor unit recruitment

Your body becomes better at activating more motor units.

More motor units recruited → more force produced.

B. Better Type II fiber recruitment

The nervous system gets better at recruiting Type II muscle fibers, which are important for high force and power.

C. Increased firing rate

Motor neurons send signals more quickly and frequently.

Faster firing → stronger muscle contraction.

D. Better synchronization

Multiple motor units can fire at the same time.

Better synchronization → faster force production → greater power/RFD.

E. Better coordination

Agonist and synergist muscles work together more effectively.

Better coordination → more efficient movement.

Motor Unit

Motor unit = one motor neuron + all the muscle fibers it controls.

Henneman's Size Principle

Motor units are generally recruited from:

Small → medium → large

Small motor units have a lower recruitment threshold.

Large motor units, including those controlling Type II fibers, require more force to be recruited.

Selective recruitment

Experienced athletes can more effectively recruit higher-threshold motor units when they need to produce a lot of force quickly.

3. Neuromuscular Junction Adaptations

The neuromuscular junction (NMJ) is where the nervous system communicates with the muscle.

Anaerobic training can cause:

• Larger NMJ area

• Longer nerve-terminal branching

• More acetylcholine receptors

• Faster action potentials

• Faster motor-unit firing

Easy way to remember:

Better nerve → muscle communication = better force production.

4. Reflex Adaptations

Muscle spindle

A muscle spindle detects rapid muscle stretch.

When a muscle is rapidly stretched:

Stretch → muscle spindle → contraction → force

Training can increase muscle-spindle sensitivity.

This can improve:

• Explosive strength

• Power

• Rate of force development (RFD)

Golgi tendon reflex

The inverse myotatic reflex/Golgi tendon reflex normally helps inhibit muscle contraction when tension gets very high.

With anaerobic training:

Decreased inhibitory sensitivity → greater force can be produced before inhibition occurs.

This contributes to increased maximal strength.

5. Cross-Education

Cross-education = training one limb causes strength benefits in the opposite, untrained limb.

Example:

You can't train your injured left leg, so you train your right leg.

Your left leg may still maintain some strength because of central nervous system adaptations.

Strength increases of about 8–22% have been observed in the untrained limb.

Remember:

Train one side → nervous system helps the other side.

6. Bilateral Deficit vs. Bilateral Facilitation ⭐

Bilateral Deficit

Bilateral deficit = both limbs together produce LESS force than the combined force of each limb individually.

Example:

• Right arm = 60 lb

• Left arm = 60 lb

• Individually = 120 lb total

• Together = less than 120 lb

More common in novice lifters.

To reduce it:

Use more bilateral training.

Bilateral Facilitation

Bilateral facilitation = both limbs together produce MORE force than the combined force of each limb individually.

More common in experienced lifters.

It is associated with increased voluntary agonist activation.

Easy memory:

Deficit = together is worse

Facilitation = together is better

7. Muscular Adaptations ⭐

Hypertrophy

Hypertrophy = increase in muscle size/cross-sectional area (CSA).

Resistance training causes mechanical tension and exercise-induced muscle damage, leading to the addition of contractile proteins within myofibrils.

Type II fibers generally hypertrophy more than Type I fibers.

Hypertrophy results in:

• Bigger muscles

• Greater force production

• Increased strength

• Increased power

Hyperplasia

Hyperplasia = increase in the number of muscle fibers.

It can occur through fiber splitting.

However, evidence is strong in animals but inconclusive in humans, and it is thought to have a relatively small effect.

Don't confuse:

Hypertrophy = bigger fibers

Hyperplasia = more fibers

8. Muscle Fiber Type Changes

Muscle fibers exist on a spectrum from less oxidative to more oxidative.

With anaerobic/resistance training:

Type IIx → Type IIa

Type IIa fibers are more fatigue-resistant.

With detraining:

Type IIa → Type IIx

Evidence that Type II fibers completely change into Type I fibers, or vice versa, is not conclusive.

Easy memory:

Training → IIx becomes IIa

Detraining → IIa moves back toward IIx

9. Other Muscle Adaptations

Anaerobic training can cause:

• Increased muscle circumference

• Increased muscle-fiber size

• Increased myofibrillar volume

• Increased strength

• Increased power

• Increased pennation angle

• Increased ATP/CP storage

• Improved acid-base buffering capacity

Acid-base buffering

High-intensity exercise causes H⁺ accumulation.

Repeated training helps the muscles become better at buffering H⁺.

Better buffering → ability to tolerate high-intensity exercise better.

10. Bone Adaptations ⭐

Bones respond to the mechanical stress placed on them.

Anaerobic training can increase:

• Bone diameter

• Bone strength

• Bone mineral density (BMD)

Bone Mineral Density

BMD = amount of mineral in a given area of bone.

Progressive loading increases BMD.

Inactivity/immobilization decreases BMD.

Wolff's Law

Wolff's Law = bone adapts to the loads placed on it.

More mechanical loading → stronger bones.

Minimal Essential Strain

The minimum amount of strain needed to stimulate bone formation.

It is about 1/10 of the force needed to fracture the bone.

Best exercises for bone adaptation:

Large-muscle, multi-joint, weight-bearing exercises.

Examples:

• Squats

• Lunges

• Deadlifts

11. Connective Tissue Adaptations

Connective tissues include:

• Tendons

• Ligaments

• Fascia

• Cartilage

Tendons, ligaments, and fascia

Anaerobic training can increase:

• Collagen fibril diameter

• Number of collagen fibrils

• Density of collagen fibrils

• Tendon stiffness

Important:

Connective tissue adapts more slowly than skeletal muscle.

Therefore:

Muscle gets stronger faster than connective tissue can adapt.

Rapidly increasing training loads can cause connective-tissue damage.

12. Cartilage

Training can help maintain cartilage health.

Weight-bearing forces through a full range of motion are important for cartilage viability.

Cartilage doesn't have its own blood supply, so nutrients move through synovial fluid.

Key point:

Moderate-intensity exercise can increase cartilage thickness.

The slides state that strenuous exercise does not appear to cause degenerative joint disease.

13. Cardiovascular Adaptations ⭐

Acute = happens during/immediately after exercise

During resistance/anaerobic exercise:

• HR increases

• Stroke volume increases

• Cardiac output increases

• Blood pressure increases

• Vascular resistance increases

Muscle contractions can compress blood vessels.

The sympathetic nervous system also causes vasoconstriction in areas that aren't exercising.

Valsalva Maneuver

The Valsalva maneuver increases pressure inside the chest.

It can:

1. Compress the aorta

2. Decrease venous return

3. Increase sympathetic activity/vasoconstriction

This is important during heavy resistance exercise.

14. Reactive Hyperemia

After finishing a resistance-training set:

Muscles relax → blood vessels open → blood flow/venous return increases

This surge in venous return is called reactive hyperemia.

After a set:

• HR can increase

• BP may decrease

• Sympathetic activity decreases

• Vasodilation increases

15. Chronic Cardiovascular Adaptations

After consistent training:

Resting blood pressure decreases

Approximately 2–4% for SBP and DBP.

The decrease is greater in people who started with elevated BP.

Resting heart rate decreases

Approximately 4–13%.

Also:

Same workload → lower cardiovascular response after training.

In other words, your body becomes more efficient.

16. Left Ventricular Adaptation

Resistance training creates pressure overload.

This can cause:

Concentric cardiac hypertrophy

Meaning:

• Left ventricular wall gets thicker

• Little/no change in LV volume

Easy comparison:

Resistance training → pressure overload → thicker wall

Aerobic training → volume overload → larger chamber

17. Pulmonary Adaptations

Acute

During anaerobic exercise:

• Respiratory rate increases

• Tidal volume increases

These increase significantly after completing a set.

Chronic

With training:

Max exercise:

• Increased respiratory rate

• Increased tidal volume

Submax exercise:

• Increased tidal volume

• Decreased respiratory rate

This can make breathing more efficient.

18. Anaerobic Overreaching vs. Overtraining ⭐

Overreaching

Short-term excessive training → temporary decrease in performance.

It isn't necessarily bad.

It can sometimes be intentionally used to "shock" the system and help with adaptation or peaking.

Overtraining

Too much training for too long + not enough recovery → extreme fatigue, illness, injury, and decreased performance.

Common causes:

• Too much training

• Not enough rest

• Not enough recovery

• Possibly inadequate nutrition

19. Overtraining Syndrome (OTS) ⭐⭐⭐

Overtraining syndrome = excessive training/recovery imbalance lasting weeks to months that results in prolonged maladaptation.

The key phrase to remember is:

PROLONGED MALADAPTATION

20. Stages of Overtraining Syndrome

This is VERY important for Question #2.

Stage 1: Sympathetic OTS

Occurs earlier.

The sympathetic nervous system becomes overly active.

Think:

OVER-RESPONSIVE

Signs:

• ↑ Resting HR

• ↓ HRV

• ↓ HR recovery

• Possible ↑ BP

Stage 2: Parasympathetic OTS

Occurs later.

The parasympathetic nervous system becomes overly active.

Think:

UNDER-RESPONSIVE

Signs:

• Lethargy

• ↓ Resting HR

• Blunted HR response during exercise

21. Volume-Related vs. Intensity-Related Overtraining

Volume-related overtraining

Think:

TOO MUCH WORK

Caused by:

• Too many sets

• Too many exercises

• Too many training sessions

• Too much overall workload

• Not enough recovery

This is a metabolic stressor.

Intensity-related overtraining

Think:

TOO MUCH NEURAL STRESS

Caused by:

• Loads that are too heavy

• Peaking too often

• Too much neural demand

• Not enough recovery between heavy sessions

This is a neural stressor.

You can also have a combination of both.

22. Sympathetic vs. Parasympathetic OTS ⭐⭐⭐

Super easy memory:

Sympathetic = SPEED UP

Parasympathetic = SLOW DOWN

During OTS:

Sympathetic first → Parasympathetic later.

23. Detraining ⭐

Detraining = loss of adaptations/performance because training is stopped or substantially reduced.

Causes:

• Injury

• Decreased frequency

• Decreased volume

• Decreased intensity

Principle of Reversibility

If you stop training, you gradually lose the adaptations you gained.

Important points:

• Power decreases relatively quickly.

• Muscle CSA decreases quickly without a stimulus.

• Type II fibers decrease more.

• Fiber-type changes occur more with longer periods of detraining.

• Strength is maintained longer in experienced lifters than beginners.

24. Retraining

Retraining = returning to training after a period of detraining.

The good news:

Adaptations usually return quickly once training resumes.

Strength and power can return especially quickly because of neural adaptations.

This supports the idea of muscle memory.