I have had the Garmin 245 since last June. It has consistently measured my VO2 max at 52-53. I'm 71 years old and this is too high. It affects the race time calculations and gives me times I've never run. My older watch the 235 had me in the upper 40's. I chatted with Garmin and they said nothing was wrong. Something is. I'm a strong runner but not that strong. Anyone else have this problem?