Welcome and thanks for your question I am Dr. German I would be here to help you and give you assistance until you are satisfied, when you are exercising ,there is a formula ,you need to subtract your age from 220 .
In your case , this would be 220 -22=198 .The normal heart rate while you are exercising would be 50-85 % of this number , for you would be from 99-168 .
This means that when you are exercising or when you are performing physical activity like climbing stairs your heart rate could go up from 99 to 168 beats per minute and that would be normal .
So at your age , this is normal that your heart rate changes like that and nothing to get worried ,specially when your heart beat rate is within the normal range levels like yours is .
If you need any additional information I will be happy to continue further and assist you until you are completely satisfied .
Good luck to you and have a good day !
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