Brief Answer:
Need to rule out pathologies first

Detailed Answer:
Hello XXXXXXX and welcome.

Thank you for writing to us.

I have gone through your query with diligence and would like you to know that I am here to help. Getting fatigued easily can at times be totally normal and at times can have some underlying cause. So our aim should be to rule out any possible abnormalities before considering this to be normal.

First let me list a few common causes for an easily fatigued status, they are:

-Low hemoglobin levels (anemia)
-Low blood glucose levels
-Poor nutrition (eg. low potassium level, etc.)
-High caffeine intake
-Lack of sleep
-Inadequate amount of exercise
-Being overweight or obese
-Thyroid abnormalities
-Depression
-Underlying heart condition
-Dehydration

I would thus recommend the following investigations to rule out any possible abnormalities:
-Complete blood count
-Blood glycemic profile
-Sleep cycle
-ECG (EKG)
-Thread mill test
-Thyroid profile
-Vitamin and electrolyte levels

If any abnormalities are noted, adequate correction will be required. Once all these reports have ruled out any abnormalities, we can assume the cause to be a poor stamina. Building stamina is not difficult, but at the same time requires determination. Building your stamina will require a regular exercise regimen, which gradually increases and pushes you to do more. This in turn will result in an increase over time, allowing you to run for longer distances and climb more flights of stairs without getting exhausted. I would also recommend complete discontinuation of smoking, drinking carbonated drinks and alcohol consumption; on the other side increase your fluid intake and vegetable intake.

I hope you find my response both helpful and informative. Please feel free to write back to me for any further clarifications, I would be more than happy to help you.

Best wishes.

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