1393 - The strong arm of the tax law

I'm sitting, or should that be slumping, here
In the once-proud department of Customs
And Excise, now HMRC, where beer
And wine and cigs and fuel are all taxed, on
Top of VAT, with duty. The sun
Has popped behind the thin cloud; cooling breeze
Snaps the blinds back and forth; window open
Upon a Salford road junction. My knees
Ache less now they've been rested for some days:
No bike rides or runs. Even walks appear
To cause a groaning somewhere in my bones
Good news though on my home exercises
I used to do forty press-ups; then sheer
Collapse. Now I do sixty. Big strong arms!