Brief Answer:
Both a/c and weight-lifting is harmful for singers

Detailed Answer:
Hello Deep and welcome.

Thank you for writing in, it is my pleasure to help you.

Vocal chords which are solely responsible in production of voice help in singing and require mucous layers to help in bringing out your voice successfully. Air conditioning (a/c) results in drying of the vocal chords, by drying all the mucous produced; this can affect your voice, and in turn your singing.

As for gymming (especially weight lifting), improper breathing technique can result in damaging your vocal chords, which can be potentially harmful for singers. So I would advice against this as well.

I hope this information helps in answering your queries. Please feel free to write back to me for any further clarifications, I would be more than happy to help.

Take care Deep and best of luck for your future.

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