Muscular System Pt 3

Fiber Architecture

Parallel: fibers run parallel to each other; less powerful; muscle can shorten better; moves body segments through large

ranges of motionEX: Biceps brachii, rectus abdominis, Pectoralis major

Fiber Architecture

Pinnate: fibers attach obliquely to a central tendon; generates more force because you can

pack more fibers into the muscle; does not shorten as much

ex: Rectus femoris, Deltoid

Muscle Strength, Power and Endurance

Strength

Amount of weight being lifted is an indirect measure of strength

More precisely – the amount of torque (rotary force) muscles can generate

Torque = product of size of force abd the perpendicular distance of that force from an axis of rotation

T= FmxdF

Power

Related to force and velocityMuscle force multiplied by muscle

shortening velocitySprinter with greatest leg strength may

not be the fastest

Endurance

Ability of a muscle to produce tension over a period of time

Usually the longer the physical activity is maintained, the greater the endurance

Definition is specific to activity (gymnast, rower, etc.)

The faster a muscle fatigues, the less endurance it has