So I don't know a lot about the heart rate. Mine's usually 45-50 BPM sitting down, walking so on and so forth.I've never seen it over 90 (after dancing) I don't know much about the heart rate other than I know my dad says his is a little high being around 80-90 "rested" Though he tends to check after working on the farm which could have it increased compared to truly rested.He has high blood pressure problems, and it's apparently genetic so I've been trying to keep mine down, I don't know if heart rate is related or not. My common Blood pressure and such is98-115 over 50-60 and heart rate 45-50 rested. But I know in exercise my heart rate has been as high as 98-110 I just don't want to get it too high and hurt myself or something.
45-50 is actually low, and technically considered to be bradycardia (which just means 'slow heart rate'). It is common in athletes and people who do regular training or working out - such people have built up their heart size (temporarily, so long as they are in training) and so it doesn't have to beat as often when resting. But it is interesting, considering that you experience fatigue, because in people with normal-sized hearts bradycardia often leads to fatigue - other symptoms that may be experienced from bradycardia include weakness, dizziness, lightheadedness, fainting, chest discomfort, palpitations, or shortness of breath. Perhaps you should get your heart checked out?You don't need to worry about high heart rate with exercise - at your age your heart rate could probably get to 180-190 without problems.Your father's heart rate is normal, though on the high end of normal.98-115 systolic blood pressure is perfectly normal, but 50-60 diastolic is a bit low. Again, low blood pressure is normal for athletes in training.