>While one might think "I can do 50 reps with low weights"
The caveat is that you need anaerobic training. Low enough weight and it’s cardio, you don’t get giant legs by walking to failure for example.
Has anyone really ever walked to failure on a regular basis? I typically have to stop because of blisters not muscle failure. (The furthest I've done is 12 miles with +10% weight.)
Well you’re not applying much mechanical tension to the quadriceps when “walking to failure”. This is nowhere near analogous.
I don't know. All cyclists I know seem to have massive thighs. And these are amateurs who don't do any kind of strength training, just hours and hours of cycling every week.