| A | B |
|---|
| all -or-none law | a stimulated muscle or nerve fiber contracts or propogates a nerve impulse either completely or not at all; in other words, a minimal stimulus causes a maximal response |
| fast-twitch fiber | a muscle fiber haracterized by fast contraction time, high anaerobic capacity, and low aerobic capacity, all making the fivber suited for high-power output activities; fatigability |
| frequency of activation | one way to to grade muscular force; increasing this so that the twitch forces are allowed to summate results in greater force developed by the motor unit; generally used in small muscles (eg. hand) |
| Golgi tendon organ (GTO) | A proprioceptor located within a muscular tendon |
| hypertrophy | An increase in the size of a cell or organ |
| kinesthetic sense | conscious appreciation of the body in 3D space; essential for executing coordinated movement and maintaining muscle tone and body posture |
| muscle spindle | A proprioceptor (stretch receptor) surrounded by intrafusal muscle fibers |
| proprioceptor | Sensory organs found in muscles, joints, and tendons, which give information concerning movement and position of the body (kinesthesis); provide the CNS with info concerning kinesthetic sense |
| recruitment | One way to increase muscular force; varying the number of of motor units activated; motor units are activated at near-fusion frequency when called; additional motor units are called upon; complete activation of the available motor neuron pooli is porbably not possible in untrained people |
| slow-twitch fiber | A muscle fiber characterized by slow contraction time, low anaerobic capacity, and high aerobic capacity, all making the fiber suited for low-power output activities; generally fatigue resistant |
| tetanus | The maintenance of tension of a motor unit at a high level as long as the stimuli continue or until fatigue sets in; twitches completely fuse |
| twitch | A brief period of contraction followed by relaxation in the response of a motor unit to a stimulus (nerve impulse) |
| contraction speed | FT=fast ST=slow |
| power output | FT=High ST=Low |
| Endurance | FT=Low ST=high |
| Aerobic enzymes | FT=low ST=high |
| Anaerobic enzymes | FT=high ST=low |
| Fatigue resistance | FT=Low ST=high |
