I'm 15 and have just started puberty. (Yes I know at a late age, I have had this checked over with my endocrinologist and have blood work just to make sure it wasn't something that would be an issue)
Lately, I have become aware of my heart and its pulse, and have began to exercise more and get into shape as my doctor told me that exercise would stimulate testosterone release and allow me to develop better, so I have began doing training with exercise bands, and going on moderate-high intensity bike rides to improve cardiovascular health.
My family has a history of heart problems, three family members almost died due to a clot in their "widow-maker" and my uncle may have suffered a heart attack when he was 30 years old. (doctors aren't sure, they just found damage to the heart)
On my bikerides, I only go about 2 or so miles, but the trail I ride has many hills and I try to keep my speed above 10 miles per hour during the whole workout. My heart rate climbs to around 160-180 and when I stop the bike ride, everything returns to normal within the first 2-3 minutes. I have a heart rate recovery of ~55 after the biking workout but my heart rate stays at ~90-100 for the next 1-2 hours.
I don't have any other symptoms, I think I have tightness in my chest, but I'm chalking that up to me over analyzing.
My real question is,
Is it normal for my pulse rate to remain high after workout? ( I know it is to a certain extent, but I haven't found anything on whether it's different for someone just going through puberty)
And does the heart grow during puberty to an extent that it will cause any noticeable changes, or what actually happens to your heart during puberty.