Is fitness deductible as a sports instructor?

Hey community, I am self-employed in secondary occupation – I teach spinning classes and do graphic design (from logos to corporate identities, from printed matter to websites and social media). While I was teaching my spinning class this morning (which I do twice a week), I wondered whether I could claim part of my fitness subscription?

I have read that if I can prove that I made purchases for the subscription for professional reasons, among other things, it would be tax-deductible. What do you think? Preparing lessons, building up cardio for my classes, building up strength training for my classes, it all sounds logical that I should be able to claim it, right?