neuromuscular

A whole muscle is divided into __________, which are individual muscle cells

muscle fibers

Muscle fibers are grouped into __________, which are bundles of muscle fibers.

fascicles

Excitation-contraction coupling (ECC) refers to the process that leads to __________.

muscle contraction

myocytes

muscle cells

Alpha motor neurons transmit an __________ to the muscle fiber.

action potential (AP)

At the neuromuscular junction (NMJ), __________ is released and binds to receptors on the muscle fiber membrane.

acetylcholine (ACh)

The signal travels down __________, activating voltage-gated Ca²⁺ channels.

t-tubules

Ca²⁺ binds to __________, which leads to actin-myosin cross-bridge formation.

troponin

A motor unit consists of a motor neuron and all the __________ it innervates.

muscle fibers

The number of fibers within a motor unit determines its __________.

function

Small motor units are responsible for __________ motor control.

fine

The size principle states that motor units are recruited from __________ to __________ depending on force needed.

smallest, largest

Low-force movements recruit __________ motor units.

smaller, more fatigue-resistant

Higher force demands recruit __________ motor units for greater power output.

larger, fast-twitch

EMG records the __________ of skeletal muscles.

electrical activity

Surface EMG uses electrodes placed on the __________.

skin

Intramuscular EMG involves needle electrodes placed __________.

inside the muscle

Raw EMG displays the __________ signals.

raw electrical

Integrated EMG processes raw EMG data to provide a __________ signal.

smoother

MVC stands for __________ maximal volitional contraction.

greatest amount of force a person can voluntarily exert

As contraction intensity increases, more motor units are __________.

recruited

During prolonged isometric contractions, motor units __________.

fatigue

After sustained contraction, muscle fatigue leads to __________ in force output.

reduction

EMG analysis can identify the most __________ abdominal exercises.

effective

EMG signals vary between individuals due to differences in muscle size, skin thickness, and __________.

fat distribution

Diseases such as amyotrophic lateral sclerosis (ALS) show __________ in motor unit recruitment.

decreased

Myasthenia gravis is characterized by reduced __________ efficiency at the neuromuscular junction.

transmission

Diseased EMG recordings may show reduced __________ in muscle activation.

amplitude

Muscle fatigue can lead to depletion of __________ and accumulation of metabolic byproducts.

ATP

The second MVC is typically __________ than the first due to muscle fatigue.

lower

Different biceps curl variations target different __________ activation patterns.

muscle

A supinated curl maximizes __________ activation.

biceps brachii

The brachialis lies __________ the biceps and is a primary elbow flexor.

underneath

Elbow flexion can also involve the __________, which contributes during neutral grips.

brachioradialis

Forearm flexors assist with grip and __________ during elbow flexion.

stabilization

Increased fatigue may show __________ decline in signal strength in EMG readings.

rapid

Integrated EMG provides a more __________ representation of muscle activation over time.

meaningful

Motor unit recruitment patterns can drastically affect __________ measured by EMG.

muscle activation

Neuromuscular dysfunctions can be evaluated using __________ EMG testing.

intramuscular or surface