Hi. I would say that fitness watches and such are not always the most accurate or reliable for readings. But, good news. That is totally within normal. Resting heart rate normal is 60 to 100 and heart rate with exercise is normal if within 160 to 220. You're good. How quickly does it come back down? If fit, it usually does so relatively quickly. Glad you are exercising and you sound normal. good luck
My advice, for what it's worth, is leave the fitbit at home. Never look at it. Return it if you can. You're apparently a very active athlete, and part of doing what you do is to get that heart rate up. It's why those of us still fit enough to do cardio do it. Wish I could still do it. When you get your regular physicals, they will check you bp and vitals and do blood test that show levels of calcium that are far better indicators of heart problems than a watch. I'm sure with time particularly given their vast resources Apple will come up with something that is accurate eventually, but even then, we all have our own levels, we're not all the same. Averages are averages, they don't necessarily mean anything to an individual. What these devices do, however, is increase anxiety, and possible even encourage obsessive thinking. People have been exercising since there have been people and somehow they all got along without a device to measure every fluctuation. Now, if you ever suffer symptoms of disease that might be heart related, then go see your doc. But if you're feeling fine, nobody can really tell even if there is something wrong. For example, if you got a resting heart test at a doc's office, it might indicate something for further investigation but by itself it's pretty useless. I had to get a heart test before a surgery, and it came out my heart was slow. Resting heart rates for athletic people can be that way. So it can indicate a heart that is working so well it doesn't have to work very hard. It can also indicate a pacemaker in my future. Absolutely, minus symptoms of disease, no way to tell, according to my doc. So it goes.