Essentials of Strength and Conditioning NSCA chapter 1

The dark band in a sarcomere where thick (myosin) and thin (actin) filaments overlap.

A neurotransmitter that triggers muscle contraction at the neuromuscular junction.

A thin filament protein in muscle fibers that interacts with myosin to produce contraction.

A rapid change in electrical charge across a cell membrane that transmits nerve or muscle signals.

A principle stating that a muscle fiber or neuron either fully responds or does not respond at all.

The pressure within the pulmonary alveoli; drives airflow during breathing.

Tiny air sacs in the lungs where gas exchange occurs.

The valve that controls blood flow from the left ventricle into the aorta.

The bones of the limbs and limb girdles (shoulder and pelvic girdles).

The network of blood vessels (arteries) that carry oxygenated blood away from the heart.

A small branch of an artery leading into capillaries.

A blood vessel that carries blood away from the heart.

The bundle of conductive fibers between the AV node and ventricles (also called the bundle of His).

A specialized heart node that delays electrical impulses before they pass to the ventricles.

Valves (tricuspid and mitral) that prevent backflow into the atria during ventricular contraction.

An upper chamber of the heart that receives blood returning to the heart.

The central framework of the body, including skull, vertebral column, and rib cage.

Joints that allow movement around two axes (e.g., wrist joints).

A dense membrane covering bone surfaces containing nerves and blood vessels.

Slower than normal heart rate, typically under 60 beats per minute.

The two main branches of the trachea that lead into the lungs.

Smaller branches of the bronchi that lead to the alveoli.

A small blood vessel where exchange of gases, nutrients, and waste occurs between blood and tissues.

Involuntary, striated muscle found only in the heart.

The breakdown of complex molecules into simpler ones, releasing energy.

The brain and spinal cord; processes and sends signals throughout the body.

Relating to the coccyx (tailbone), the final segment of the vertebral column.

Part of muscle responsible for generating force (primarily actin and myosin).

The connection between actin and myosin filaments during muscle contraction.

A change in a cell's membrane potential, making it more positive and triggering an action potential.

Movement of molecules from an area of higher concentration to an area of lower concentration.

Farther from the center of the body or point of attachment.

The phase of the heartbeat when the heart muscle relaxes and fills with blood.

Connective tissue that surrounds the entire muscle.

Connective tissue that surrounds muscles, blood vessels, and nerves.

Bundles of muscle fibers grouped together within a muscle.

Muscle fiber type that contracts quickly and powerfully but fatigues rapidly.

A lever where the fulcrum is between the effort and the load (like a seesaw).

A sensory receptor that detects tension in tendons and helps prevent muscle damage.

A muscular organ that pumps blood throughout the body.

A protein in red blood cells that carries oxygen.

The upper arm bone connecting shoulder to elbow.

Muscle fibers inside muscle spindles that detect stretch.

A byproduct of anaerobic metabolism, associated with muscle fatigue.

Organelles that produce ATP, the energy currency of the cell.

The valve between the left atrium and left ventricle of the heart.

A nerve cell that sends signals from the nervous system to muscles.

A single muscle cell, long and cylindrical in shape.

Threadlike structures in muscle fibers made of actin and myosin, responsible for contraction.

A thick filament protein that pulls on actin to cause muscle contraction.

The site where a motor neuron communicates with a muscle fiber.

A nerve cell that transmits electrical signals throughout the body.

The fixed attachment point of a muscle.

The part of the autonomic nervous system that conserves energy and slows the heart rate.

The kneecap; a small bone in front of the knee joint.

Connective tissue surrounding bundles of muscle fibers (fasciculi).

All nerves outside the brain and spinal cord.

The liquid portion of blood that carries cells and proteins.

The membrane surrounding the lungs and lining the chest cavity.

Closer to the center of the body or point of attachment.

Circulation of blood between the heart and the lungs.

Fibers in the heart that carry electrical impulses to cause ventricular contraction.

An index of myocardial oxygen demand; heart rate × systolic blood pressure.

A cell in blood that carries oxygen using hemoglobin.

The electrical charge across the membrane of a resting neuron or muscle cell.

The cell membrane of a muscle fiber.

The functional contractile unit of a muscle fiber.

The cytoplasm of a muscle fiber, containing organelles and glycogen.

Organelle in muscle fibers that stores and releases calcium for contraction.

A lever where the load is between the fulcrum and effort (like a wheelbarrow).

Valves between the ventricles and the arteries (pulmonary and aortic valves).

A nerve cell that carries signals from sensory receptors to the central nervous system.

Voluntary muscle attached to bones, responsible for body movement.

Muscle fiber type that contracts slowly and is resistant to fatigue.

The explanation of how muscles contract via actin and myosin interaction.

The part of the central nervous system that runs through the spine, relaying messages to and from the brain.

An organ involved in filtering blood and immune responses.

The breastbone; located in the center of the chest.

Having a striped appearance due to repeating sarcomeres, characteristic of skeletal and cardiac muscle.

The amount of blood pumped by the heart in one beat.

Located or applied under the skin.

Part of the autonomic nervous system that prepares the body for action ("fight or flight").

The junction between two neurons or a neuron and a muscle cell.

A freely movable joint enclosed in a capsule filled with synovial fluid.

Circulation of blood from the heart to the body (excluding lungs) and back.

Connective tissue that attaches muscle to bone.

The rib cage; protects the heart and lungs.

The part of the body between the neck and abdomen, containing the chest cavity.

The minimum stimulus required to cause a muscle contraction or nerve impulse.

A protein that blocks binding sites on actin in a relaxed muscle.

A protein that binds calcium and moves tropomyosin, exposing binding sites on actin.

The central part of the body, excluding the limbs and head.

A slow-twitch muscle fiber; fatigue resistant and used for endurance.

A fast-twitch muscle fiber with both power and endurance characteristics.

A fast-twitch muscle fiber that fatigues quickly; used for explosive power.

The inner and longer of the two bones of the forearm.

A joint that allows movement in one plane (e.g., elbow).

Structures that prevent the backflow of blood in the heart and veins.

Enlarged, twisted veins often caused by faulty valves.

A blood vessel that returns blood to the heart.

The flow of blood back to the heart via veins.

A chamber of the heart that pumps blood out to the lungs or body.

One of the individual bones that make up the spinal column.

A blood cell involved in immune defense.

The boundary of a sarcomere where actin filaments are anchored.