While the wattage may be more readily quantified, and compared, via the use of an accelerometer, the degree to which the CNS is stressed would be most accurately measured via, as one example, Omega Wave technology.
A note, I have found repeated success with my American footballers, regarding squat work during SPP, in waving the load between 50-70% and NOT lifting the weight explosively.
While the nature and demands of our training and competition are distinct from the sprints in T&F the similarities exists as the training impacts yielded via the performance of the more CNS intensive training (ergo sprints, jumps, throws, etcetera) and, thus, how the organism is effected via the cumulative result of these different stressors.
It’s a balancing act.
I think many would be surprised to find out how effective sub-maximal weight training is, regarding lifts that affect the muscles that mobilize the sport act, with respect to retaining previously concentrated efforts so long as the load is compensated for via the concentrated performance of training means that have a more direct impact on improving sport results (ergo SPP as contests draw near)
More similar to a T&F event, none of my pro-day guys squatted during the final 4 weeks of their preparation; and instead, performed only explosive strength movements in the form of squat jumps with a kettlebell, depth jumps, and SLJ and nearly all of them set significant PRs in the 40yd, VJ, and SLJ.
This is not to state that this is the only way; but merely to instill confidence in those who may fear the idea of getting too far away from a certain training means.
Important to note is that intensive training means may effectively be cycled in and out of the training so long as the sequential superimposition of the new means positively/smoothly builds upon the foundation laid by the preceding means.
While one of the many advantages of Charlie’s Vertical Integration is, to the contrary, the generally always present existence of all means used in the training (with only the volumes varying) it is important to understand that adaptation stiffness only results when the ‘new addition’ to the training was not effectively prepared for, OR, if the new training means is introduced in a fantastically voluminous fashion (ergo American football training camp) .
While I would not universally recommend a strict block approach to all comers (as the model that I use for our annual plan does not strictly adhere to block model as it is described in the literature); there is no question as to its efficacy when appropriately used.