Hello.

Thanks for your query.

There are two points to be noted here about pounding headache.

First you have the headache during change of postures which can be related to large variations of blood pressure due to posture change. So it is important to check the blood pressure during each of these postures.

Second is McArdle's disease. It is a glycogen storage disease associated with myopathy.
Normally it is not associated with any headache but if there is a prolonged exercise then the muscles start using alternative sources of energy like fatty acids, etc and this might cause mild headache due to accumulation of breakdown products or lactic acid.

If the headache is there in the resting state or on minimal effort then there might be a different cause that needs to be explored.

Hope I have answered your query. I will be available if you have any further queries.
Regards

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