But it doesn't shift the dissonance. If i'm at low miles (because athletic background) b/c im slow then it would make sense to progress my speed, no? And yet of the the various variables that's one you're being told to go backwards in.
Literally all of my objections amount to this, is it ok to do a 40 minute run where you're only getting 5km of distance covered? how does this help make me a faster runner? also if you look at basketball studies, the average HR for a player over the entire match (including dead periods) is 160-180bpm. So would it make sense to do more training closer to that range than say 140. I know what the argument is for long slow running (if you accept it and even if i did) it runs into a wall cos weekly mileage wud be so low to not offer much benefit to faster runs. tbh i can see how it 'could work' if you were sufficiently fast then going submax you can still get a decent amount of km done
the answer to the question i bolded is, "yes, if that is a moderately challenging effort for you." low intensity steady state cardio is a tick or two above walking; you should be able to have a conversation with someone but not without having to catch your breath once in a while. if you're really overweight or have emphysema, then maybe walking is the quickest you can do, in which case covering 3 km in 40 minutes is ok. building aerobic capacity makes you faster for sports by, among other things, improving your body's ability to recover from bursts of effort. that was what i noticed during my ultimate game last spring: i wasn't necessarily any faster at max speed, but i could reach max speed -- and change direction quickly -- more times over the course of multiple points. that made a big difference in my capacity on the field.
i think you're making a mistake that a lot of people do, myself included, which is assuming too direct a correlation between two different data points. you think "basketball is played at 160-180 bpm, jogging gets me to 140 bpm, therefore maybe jogging isn't an optimal way to train for basketball." but jogging and basketball are different activities, and jogging can absolutely help build physical capacities that improve your ability to do specific training for and to play basketball. it's GPP. same as squatting: there isn't a 1:1 relationship between squatting and basketball ability, to claim one would be silly. but getting a bigger squat has carryover into speed and jumping and boxing people out. jogging has carryover into not getting winded as easily during gameplay.