Brief Answer:
100 years - you can be active.

Detailed Answer:
Hi XXXX
I am Dr. Prakash HM and I would like to answer your question.

Aging is an ongoing process. It is associated with certain degenerative changes in various organs like musculoskeletal system, reduced vision and hearing, neurological deterioration and malnutrition secondary to reduced intake and malabsorption.

For your question, I would say "No".

Once somebody told on his 100th birthday - "If i had known I was gonna live this long, I would have taken better care of myself"
You have to compare somebody with your age to assess your tiredness. Of course, you know you cannot run with somebody in their fifties too, unless you are actively into exercise. You have an activity limiting condition - Sciatica. Otherwise all other tests are normal and you need to get on with mild to moderate exercise and well nourished diet.
Exercise is important - "To live effectively, with a real purpose and not merely to exist, you must be active, interested, involved - both physically and mentally" - XXXXXXX J Frankel

Tiredness indicates reduced nutrition and physical and mental inactivity.
It is never normal. You might require more rest due to various changes in your body as told earlier, but if you get actively involved, then it should improve.

Try to maintain a good physical and mental activity along with balanced diet for six months. After six months, you will definitely feel good. Extra supplements for protein, vitamins and calcium can be taken as necessary.
Take care.
"Nothing ages like happiness"
If you have any further queries, do ask again. Always available to help you.
Thanks for asking.
Dr. Prakash HM

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