I have a Forerunner 35, I am a runner of many, many years, and now I am slower than I used to be, of course. ButrI really do great for my age (69) After a consistent VO2Max of 45-46 for weeks, all of a sudden my number started to go down daily. It went down to 35 in 10 days, I dont think it is me (I havent changed my training much at all, nor my ability and characteristics. Did a factory reset, then also deleted four folders on the computer Connect Express acct, did another hard reset, and went to run a mile or two at my top max HR level. I ran a mile in 9:43 today, which is great for me nowadays, and thought I would have earned at least a 44 or 45, if not slightly more (my usual 46). I earned myself today, a 36 only. All of this started since I did a software update on the watch, because it wasnt recording any sleep data or steps.Any ideas out there about what could explain this? A daily down trend in the VO2 max, makes no sense.