I am transferring my Gym ( and yoga studio) membership for 6 months. Each month costs 89 and you have unlimited access to the gym and the yoga classes, including the wellness area. It is very central and great for people working or living around Implerstrasse or Goetheplatz. The gym is in Lindwurmstrasse, here is a link so you can take a look at what they offer:
If you do a contract with them it has to be a two year contract, but since I already used it for 1.5 years you would only need to pay for the next 6 months, starting anytime after the middle of August. If you later want to keep the membership you might be able to keep my antiquity and only make a one year contract with them.
If you are interested PM me so we can arrange details.