In Jainism, going to the gym is not inherently paap.

What matters is the intention and conduct:

• If it is done for health, discipline, and maintaining the body for dharma, it is generally not considered paap.
• But if the gym activity involves violence, harm, ego, intoxication, or attachment, then it can become spiritually harmful.

From the Jain point of view:

• Body care is allowed, because the body is a साधन for sadhana.
• But excessive attachment to body, appearance, or pride should be avoided.
• Any activity should be done with ahimsa, संयम, and moderation.

So, gym itself is not paap in Jainism, but the bhav behind it matters.