I've just been confirmed as T1 (LADA) rather than the T2 my GP/DSN thought. (I've been on insulin since early 2017). I picked up this thread as I've been having big challenges with aerobic exercise causing rapid BG drops (starting from around the end of 2017). I can totally relate to NoKindOfSusie, and the issues she describes. I can only dream of doing the long cycle rides or walks I used to do a few years ago. But everyone is different and I'm happy for those T1s who can. My aerobic BG drops are fairly spectacular: 15 mins brisk walking or 10 mins biking drops 3-4 points 20 mins walking and I can be close to hypo 10 mins very brisk walking once caused a 6 point drop 20 mins vacuuming generally drops 3 points I used to find badminton needed juggling extra carbs during play to maintain BG - testing every 10 mins. However, in the past month my body seems to have decided that badminton is now anaerobic exercise, and a couple of weeks ago my BG rose from 8 to 15 at the end of an hour's play (without eating carbs)... My Freestyle Libre (self funded) often shows vertical down-trends and I have to be soooo careful then (as Libre's interstitial fluid measurement lags 15mins behind BG, I will then fingerprick to check where I actually am). Occasionally my BG drops are so rapid that Libre presumably cannot believe it and responds with "sensor error, try again in 10 mins" or similar. Later when I look at the trace it will have a gap. I've watched: I also found this article useful: http://www.diabetesincontrol.com/ex...justing-insulin-dosing-for-physical-activity/ Paradoxically, I use my rapid BG drops to manage post meal spikes with carefully "calibrated" walks. I just wanted to put my experience "out there". I'm not expecting any magic answers for myself, though.