Good morning. I am a 65 year old guy, using Fenix sapphire 6 and a Garmin chest strap/monitor. According to the “chart” graphic display, yesterday I averaged 135bpm for 30 mins peaking at 145 on an elliptical cross trainer. On checking the Garmin app on my mobile this morning I’m astounded to see my recorded max pulse at around 194bpm ~ which to me clearly is beyond my physical/ mechanical capacity, in part due to age, but also regardless of age, the workout could not have produced that HR even if I was in my 20’s. I have read a few txts on this site suggesting optical and electrical pulse reading differences. Can anyone tell me which I should take notice of. I. Still upright this morning so I guess the 194 is just a little fanciful….