Query on nominal code

I am sole proprietor of my own gardening business. Through a recent big, strenuous job I picked up a few slight muscle pulls in my back. To try and help the recovery, I had a professional massage done. This wasn’t for pure relaxation, more a business need to aid the recovery. Can I therefore class it as a business expense (allowable?), and if so, what nominal should I post the cost to? Would be grateful for any thoughts/suggestions on this.

Unfortunately I don’t believe massage therapy is an allowable expense due to there being an element of personal benefit (relevant thread here on the subject). I must confess I am not an accountant so it’s always worth seeking professional advice.