Hi and welcome to XXXXXXX Thank you for your query.
It would be easier if you ve told me the exact level of blood calcium.
If this is elevation higher than 3.1 mmol/L (12.2 mg/dL) it can be significant for some parathyrod gland disorder so you should evaluate this.
Hypercalciema usualy dont cause any symptoms and this shouldnt prevent any sports activities. If he doesnt have symptoms such as fatigue,muscle and bone pain, then this elevation is proably minor.
But as I said,try to rule out this what I ve mentioned above just to be sure that there isnt some hromonal imbalance which can be easily terated by certain medicines.
WIsh you good health. If you have any question I ll be glad to help.

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Ok, then it can be something more serious and it can cause certain diffiulties. I suggest to do further testing because triathlon is extremely demanding activity which can provoke serious heart incidents. YOu must be sure that there is no even minor heart disease when you do such sports.
If calcium score is higher than 150 you should do do ergometry and holter ECG for the beginning. I suggest not to exercise till your cardiologist allow you to do it. If ergometry testing is normal you can continue with your sport, but you should do cardiologic check up on annual base and avoid risk factors of course( smoking, bad food, high sugar and lipids levels).

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