Volume/Intensity ratio, niji. You won't typically feel any soreness during the exercise itself unless you're really pushing it, but the more you exercise, the more you reach for your boundaries.
When I first started, I did things like bicep curl sets of 30 repetitions with 5 kg on each hand - nowadays I do sets of 30 or 40 with 20 kg (depending on what other exercises I've got lined up). If I did now what I did then I wouldn't even feel a tingle, but with what I do now I'm in a good place where I'm not pushing too hard but I'm not dicking around either.
Now if only I could control my diet, I might lose more weight.
I sometimes feel my muscles stiffen and sometimes not. Sometimes I go a bit overboard (sets of 200 stomach crunches anyone?) and I need to lay low for a bit.
...You know, I just realized that out of context that might sound like I'm some kinda fitness nut... >.>;;
indeed, nonetheless, regardless of how hard i push, what soreness i get never comes until several days later, if at all.
i heard of one guy that never gets sore at all, he was on stan lee's superhumans - turns out he can't build up the fatigue chemical faster than his body can dispense with it. so he can literally run for an entire day with no cramps or soreness afterwords.
