NUFFIELD Health has bought nine Virgin Active Health Clubs, including the Taunton site.
The gym in East Reach - previously known as Esporta - will complement the services offered by Nuffield Health Hospital, in Staplegrove.
Hospital director Sasha Burns said: “We're excited to be working with the new gym.
“By combining our expertise we can offer more local people access to a range of health professionals and services that can improve their health and wellbeing.”
Nuffield plan to introduce new services to gym members, including a free Health MOT and access to experts from health mentors to physiotherapists and nutritionists.