How to keep a good pace

I was able to swim consistently for an hour at 2:21/100yd. I felt comfortable was able to think on random things for several laps but I can't stop thinking what am I missing to keep a good pace under 2 min?, I saw post of people swimming for couple hours at 1:30min/100m how!?!. I mean I tried but then I get tired or my muscles start burning. I can keep that 1:30 for maybe 200m but 1h seems impossible lol. submitted by /u/virtualdvid [link] [comments]