Respected user, hi I evaluated your query thoroughly.
*
Chest pain is due to decreased lung compliance in regard to exertion given
by the body relates to - decreased oxygenation - excess mouth breathing
- low levels of
Haemoglobin, lack of
proteins , trace elements,
vitamins,
minerals.
*Black out vision is related to decreased perfusion levels mostly dehydration
state.
*What all you have to do is :
@ Make him properly hydrated before gym by giving more liquids preferably
lemon juice , coconut water, rice water , green tea etc.
@ Get his haemoglobin level checked.
@ Give him diet containing more proteins , iron , vitamins , minerals, trace
elements.
@ Make him to perform deep breathing exercises with
YOGA for 30 min.
daily at home without failure.
@ Avoid more oily / spicy / junk foods / beverages .
Hope this clears your query.
Thanks for using Health Care Magic & keeping trust in our services.
Feel free to ask any further health related issues.
Wishing your child a fine happy healthy life ahead.
Regards dear.