Person X
How many reps do you recommend for my working sets?
Helder
There are reps and then there are reps, the reps that really matter for me are the so called stimulating reps. A stimulating rep involves the recruitment of high-threshold motor units and therefore the activation of their associated muscle fibres, and a slow shortening velocity, meaning it’s challenging enough that the movement becomes slower and harder as a byproduct.
Person X
How do I know many stimulating reps I have done?
Helder
This is largely dependant by the effort involved in performing a movement. When we lift a heavy load, or move a light load explosively, or lift a load to muscular failure, we are using a high level of effort and motor unit recruitment is high.
However, simply recruiting the motor units is not enough. We need to expose the muscle to high levels of mechanical loading. Going back to what I said earlier, a slow shortening velocity, meaning it’s challenging enough that the movement becomes slower and harder as a byproduct.
Person X
Ok, so if I do 8 reps and the last 5 reps are very hard to a point where the movement becomes slow, does this mean the last 5 reps are stimulating reps?
Helder
Yes, absolutely. Those 5 reps are what really matters and those are the reps that should count towards your volume of work.
Person X
Should I always go to failure?
Helder
Training to failure is often a good way of measuring training volume, because every set to failure usually contains the same amount of stimulating reps. When we do not perform a set to failure, it is not clear how many stimulating reps are done.