then it says this…
" M: No, you’re right. According to muscle-fiber physiology, the all-or-none principle states that a fiber either fires completely or not at all. So from that standpoint a lot of fibers are firing all out even with light weights and not going to failure. Did most of the pros you trained with go to failure on their work sets? What about Padilla?
No, that is NOT what the all or none principle is pointing to. It’s pointing to a fiber twitch, not that a fiber fires with full tension or not at all. Everyone gets that wrong…(sorry that idea always bugs me when mis-used )
Fibers CAN fire and do fire, with variable tension.
Email directly to me from Roger Enoka
Good morning Ron,
It is important to realize that motor units are probably never achieve a fused tetanus during a voluntary contractions. The rate at which action potentials are generated is only ever sufficient to produce an unfused tetanus, which is less than the maximal force a motor unit can produce. Of course, the force produced by a motor unit during an unfused tetanus can range from low to high, but it is never maximal. We do not know why rate coding is never enough to achieve a fused tetanus.
I hope this helps.
Roger M. Enoka, Ph.D.
Room W205B, Ramaley
Department of Integrative Physiology
University of Colorado
Boulder, CO 80309, USA