So I would say my endurance is okay, my record is 1:35. But by next this upcoming february I would like to be able to hold a HS for at least 3:30. I am currently working on doing intervals, so like 45 secs on and 1 min off and as it gets easy take 10 sec off the resting time, and many more exercises (wall hold, holding hs, etc.) I was wondering if anyone has any other great endurance exercises for me? Any tips what so ever? Any diet changes specific to endurance training (my dad says diet is important with endurance)? And is this goal even possible for me? Thank you.