Tuesdays and Thursdays 7pm at Lambton Street do a fitness/boxing session. It's good like, only £3. Do a bit of fitness and also do some pad work, bags, sparring, technical stuff, etc. all relaxed atmosphere and no dickheads. If you are any good they will train you up for the team if you were looking to take it further.

Lambton Street boxing been about as long as I can remember (and im old).

Lambton Street Boxingclub
Might give this a gan
I’m taking a look at a boxing place near to where I work in Nottingham.

They do coaching via the university that I work at.

One of the coaches is this lad:

Jawaid Khaliq - Wikipedia
It's a great way to get in shape and lose pounds like. Don't realise how unfit you are until you are in the ring with someone and you are blowing out of your arse after 30 seconds of padwork, nevermind actual sparring/fighting!