Having trouble with a few definitions for muscles

Can't figure out contraction phase, passive force, total force and  relaxation phase

Any help would be helpful.



_____  Muscle Fatigue      A.  Decreased force after stimulation and contraction stops

_____  Contraction Phase      B.   Sum of active and passive forces

_____  Isometric Contraction      C.   Increased force with relaxation between contractions
                       seen during muscle warm up

_____  Passive Force         D.  Smooth, sustained contraction

_____  Lag Phase         E.  Force produced by contraction of muscle fibers

_____  Total Force         F.   Second stimulus before relaxation causes increased
                      force

_____  Tetanus         G.   Decreased force due to lactic acid build up and
                      low ATP

_____  Relaxation Phase      H.   Tension changes; muscle length constant

_____  Isotonic Contraction       I.   Actin and myosin actively overlap as they shorten
                      the sarcomere

_____  Active Force          J.  Stimulation of additional motor units

_____  Motor Unit         K.  Force produced by elasticity of muscle fibers

_____  Treppe            L.  Time from stimulation to beginning of contraction

_____  Wave Summation      M.  Tension constant; muscle shortens

_____  Recruitment         N.  One motor neuron and all muscle fibers it innervates