Do you know your max heartbeats from running ? Was this measured with a chest strap ? Did you drink energy drinks before or take Rhodolia ? This will raise your heartbeat up to 20 beats. My garmin sometimes gives me really high readings on the couch, when i did not take it off and wash and dry it properly, and i will not trust it on zone 5. Did you put on sunscreen. If it is wrist monted is really higher than this wrist bone bump, it should not sit on zhe wrist bone, i wore my watch to low , near the hans for along tiw. Depends on the level of opponents and if they can make me run like a poor bunny, but at 53M normally below 130 average, 46 to 50 beats on the couch. Try cycling to the club, if it is just 20 to 25 mins away, thats a good warmup and cooldown.
No chest strap and no energy drinks prior to playing. I think it’s a combination of being rather unfit and playing intensely. Since it’s singles, I’m running for every ball and by the end of session I was shattered. This usual happens each time I play on a weekly basis so I think that answers that. Seems like similar folk have similar stats when playing singles.
