I swim at the Hampstead lido (not to be confused with the Hampstead ponds) in the mornings before work. It's the nicest pool I've come across in London and the staff are also incredibly nice.
I go before work and it's £2. Gets pricier (£4 something…
Hi, if Crouch End isn't too far for you then I definitely recommend Nakama. Lovely (if a little slow) staff and great food
http://nakamarestaurant.co.uk/