ISSA CERTIFIED FITNESS TRAINER
COMPREHENSIVE STUDY GUIDE 2026
◉ smooth muscle.
Answer: Involuntary muscle found inside many internal organs of
the body
◉ skeletal muscle.
Answer: A voluntary muscle that is attached to the bones of the
skeleton and provides the force that moves the bones.
◉ connective tissue.
Answer: A body tissue that provides support for the body and
connects all of its parts
◉ Sarcoplasm.
Answer: cytoplasm of a muscle fiber
◉ Glycogen.
Answer: the stored form of glucose found in the liver and muscles
◉ Myofibrils.
,Answer: Parallel filaments that form muscle
◉ Myofilaments.
Answer: filaments of myofibrils, constructed from proteins,
principally myosin or actin
◉ Actin.
Answer: the thin filaments of muscle myofilaments where myosin
bind to contract muscles
◉ Myosin.
Answer: the thick filaments of myofilaments with a fibrous head,
neck, and tail that bind to actin
◉ sarcomere.
Answer: Contractile unit of muscle
◉ z line.
Answer: A dark thin protein band to which actin filaments are
attached in a striated muscle fiber, marking the boundaries between
adjacent sarcomeres.
◉ Endomysium.
,Answer: Connective tissue surrounding a muscle fiber
◉ Epimysium.
Answer: a sheath of fibrous elastic tissue surrounding a muscle.
◉ Fasciculi.
Answer: bundles of muscle fibers
◉ Perimysium.
Answer: The connective tissue that surrounds a bundle of muscle
fibers
◉ Tendon.
Answer: Connects muscle to bone
◉ Periosteum.
Answer: a dense layer of vascular connective tissue enveloping the
bones except at the surfaces of the joints.
◉ neuromuscular junction.
Answer: the junction between a nerve fiber and the muscle it
supplies
, ◉ Neurotransmitters.
Answer: Chemicals that transmit information from one neuron to
another
◉ Acetylcholine.
Answer: A neurotransmitter that enables learning and memory and
also triggers muscle contraction
◉ sliding filament theory.
Answer: theory that actin filaments slide toward each other during
muscle contraction, while the myosin filaments are still
◉ Type 1 fibers (slow twitch).
Answer: Slower contracting, but contract for longer periods of time;
endurance activities
◉ Type 2A fibers (fast twitch).
Answer: moderately fatigable muscle fibers with moderate
mitochondrial density; used in high intensity exercises requiring
strength and power
◉ type 2x fibers (fast twitch).
COMPREHENSIVE STUDY GUIDE 2026
◉ smooth muscle.
Answer: Involuntary muscle found inside many internal organs of
the body
◉ skeletal muscle.
Answer: A voluntary muscle that is attached to the bones of the
skeleton and provides the force that moves the bones.
◉ connective tissue.
Answer: A body tissue that provides support for the body and
connects all of its parts
◉ Sarcoplasm.
Answer: cytoplasm of a muscle fiber
◉ Glycogen.
Answer: the stored form of glucose found in the liver and muscles
◉ Myofibrils.
,Answer: Parallel filaments that form muscle
◉ Myofilaments.
Answer: filaments of myofibrils, constructed from proteins,
principally myosin or actin
◉ Actin.
Answer: the thin filaments of muscle myofilaments where myosin
bind to contract muscles
◉ Myosin.
Answer: the thick filaments of myofilaments with a fibrous head,
neck, and tail that bind to actin
◉ sarcomere.
Answer: Contractile unit of muscle
◉ z line.
Answer: A dark thin protein band to which actin filaments are
attached in a striated muscle fiber, marking the boundaries between
adjacent sarcomeres.
◉ Endomysium.
,Answer: Connective tissue surrounding a muscle fiber
◉ Epimysium.
Answer: a sheath of fibrous elastic tissue surrounding a muscle.
◉ Fasciculi.
Answer: bundles of muscle fibers
◉ Perimysium.
Answer: The connective tissue that surrounds a bundle of muscle
fibers
◉ Tendon.
Answer: Connects muscle to bone
◉ Periosteum.
Answer: a dense layer of vascular connective tissue enveloping the
bones except at the surfaces of the joints.
◉ neuromuscular junction.
Answer: the junction between a nerve fiber and the muscle it
supplies
, ◉ Neurotransmitters.
Answer: Chemicals that transmit information from one neuron to
another
◉ Acetylcholine.
Answer: A neurotransmitter that enables learning and memory and
also triggers muscle contraction
◉ sliding filament theory.
Answer: theory that actin filaments slide toward each other during
muscle contraction, while the myosin filaments are still
◉ Type 1 fibers (slow twitch).
Answer: Slower contracting, but contract for longer periods of time;
endurance activities
◉ Type 2A fibers (fast twitch).
Answer: moderately fatigable muscle fibers with moderate
mitochondrial density; used in high intensity exercises requiring
strength and power
◉ type 2x fibers (fast twitch).
