A number of EMS sessions will add to the overall training load and shift its role from tone setting more towards muscular work.
My original experience with EMS was in the Godfrey study in the early 70s.
I was tested at the start and again after two days and I demonstrated a HUGE increase in power on a cybex- above 50% more force. This of course should make no sense but could be explained by the fact I had been doing hard training leading in, making the ratio of fired (unavailable) higher and non-fired (available) lower.
The EMS picked up addn’l fibre I couldn’t recruit on my own from the fibres the body normally holds in reserve (especially white fibre), thus allowing more fibre to operate in unison, and when, in that same unison, this fibre shifted back to unfired, I had a far higher pool of fibre available to use voluntarily.
As the CNS was bypassed, and as the strength gain was measured after two days of EMS in a row, it seemed obvious that this fibre cycling operated over a 24hr rather than 48 hr period.