Objective: To investigate the long-term effects of targeted follow-up of new fitness center members compared to usual practice, on frequency of visits and membership terminations after four years.

Design and setting: A participant and provider blinded parallel group randomized controlled trial conducted at eight Fitness Centers in Trondheim, Central Norway.

Participants: The inclusion criteria were new members >16 years who between September 1st to 9th 2014 signed up for an ordinary contract with a minimum duration of 12 months.

Intervention: The intervention consisted of two phone calls and one e-mail delivered over 6-8 weeks after enrollment, aiming to motivate members to get started using the fitness center and its services. Usual practice at the fitness center is self-directed use.

Inclusion Criteria:

• The study included new members (16 years in 2014 or older) on ordinary contracts with a minimum duration of 12 months and monthly automatic membership renewal that enrolled independent of the study at one of eight 3T-Fitness Centers in Trondheim between September 1st and September 9th, 2014.

Exclusion Criteria:

• Exclusion criteria were members with free contracts, employee contracts, cash membership, shorter membership contracts (duration <12 months) and loyalty contracts (indicates that the member is improving his old contract and is not a new member).