NOW IS THIS TRUE ??????????? WHY WAS OUR STRENGTH GAIN SO FAST IN INITIAL MONTHS OF JOINING????????????
There are something called as MOTOR NEURONS, these are neurons in our CNS, the axons of these comes out of CNS and control our muscles.
Now this motor neuron connect muscle fiber and that connection is called neuro muscular junction.
Now One Motor neuron and to how many muscles fibers it is connected is called ONE MOTOR UNIT. according to ALL OR NONE PRINCIPLE (BOWDITCH LAW) - when motor unit innervates all muscle fibers in that motor unit has to contract. eg: one motor unit of thigh will control 1000 muscle fibers, while one motor unit of eye will control 10 muscle fibers (muscle needing very minute movements need less muscles fibers for 1 motor unit)
A muscle (eg. gastrocnemius) can have multiple motor units controlling various groups of muscle fibers in it.
HOPE YOU UNDERSTOOD TILL HERE.......... ;-)
NOW HOW DOES STRENGTH GAIN HAPPENS..
THESE ARE THE TWO MAIN POINTS..
1. MOTOR UNIT RECRUITMENT- Increasing the number of active motor units
2. RATE CODING- Increasing the firing rate (firing frequency) at which individual motor units fire.
eg: Now lets imagine my pectoralis major has 50 motor units,
1.in chest workout, when i newly joined gym first time then i was used to using only 10 motor units so less muscle fibers were contracting and gradually the number of motor units involved increased and more muscle fibers started contributing thus more strength gains
2. When nearly all motor units are recruited, increase in firing frequency becomes the predominating mechanism to increase motor strength.
thus when all these 50 motor units are firing the speed of firing will increase, as while contracting small small same amount of signals are sent with small gaps between each signal and these gap or in between time of relaxation reduces, and it keeps on continuously firing and further increasing strength...
AND ONCE WE REACH ABOUT THE MAXIMAL OF THESE ADAPTATION (our weight lifting capacity hits plateau), HYPERTROPHY IS THE ONLY WAY TO GAIN STRENGTH FURTHER.
