Brief Answer:
follow the advises.. maintain a healthy lifestyle..

Detailed Answer:
Hello XXXXXXX Welcome to HCM..

I've gone through query and understand your concern..

Now in an otherwise healthy male (since you've not mentioned any ailments, I'm assuming that you don't have any significant past/present medical history) , the best way to replenish weakness is by taking well-balanced diet with a proper hydration..it's always advisable to compensate naturally with a proper diet plan at first..

Take protein rich diet(animal protein like eggs,fish, meat products sp.white meat as well as veg protein like cottage-cheese, legumes, soybean, nuts) along with green vegetables(simple salad will do) and plenty of fresh fruits(since it's summertime, go for water containing fruits like watermelon,lemons,pineapple etc.) ..

A good hydration is a must specially during the summertime as you'll need to compensate for the heat and sweating(even dehydration and electrolyte imbalance can cause weakness too), avoid fizzy carbonated beverages and start drinking a lot of water(3-3.5 ltr per day)..

Also let me know any other problems are you facing apart from the weakness?

Is it a whole body weakness or any particular part ?

When was your last health check-up was done and how was the report ?

Are you getting enough sleep?(remember, to stay healthy our body must need a proper 8 hr of sleep per day)..

If you feel despite of following all of the above mentioned advises, still weakness is persisting then I'd advice to get checked by any of local physician at first to rule out any significant metabolic deficiency then probably consider starting multi-vitamin supplementation as per your need (it varies from person to person so you may need to get investigated accordingly at first)..

Please let me know if there's any further query , I'll be glad to clarify..

Take Care
Regards

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