Does anyone take into account the kind of activity done during the day? For example, if I go on cycling trips, I can do perfectly fine with 4-6 hours of sleep

Does anyone take into account the kind of activity done during the day? For example, if I go on cycling trips, I can do perfectly fine with 4-6 hours of sleep per day. On the other hand, during revision times when I try to cram as much as possible into my poor memory, I tend to sleep a lot, i.e. 12-14 hours per day (and work/revise for about 6, tops). Under normal conditions, I still prefer 8-9 hours of sleep (and conversely ~10 of work).