Brief Answer:
Yes, this is not totally unexpected!

Detailed Answer:
Hi,

Thanks for this query. I have reviewed your information fully. While a knee replacement might cause pain during exercise, it should not cause you to be unnecessarily tired during exercise.

If this is a recent occurrence, I will say you should get your cardiac function evaluated too, as this is the most common cause of tiredness during exercise.

What medications are you on at this time ?

With healing going great, another approach could be to allow for full healing and recovery. If the tiredness persists even after this, then we need to go more aggressive for a comprehensive clinical and laboratory evaluation targeting the heart, thyroid and red blood levels.

I hope this helps address your worry. Let me know what plan you may want to adopt at this time and I will provide more insights along that line.

Regards

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