How European Fans in Training (EuroFIT), a lifestyle change program for men delivered in football clubs, achieved its effect: a mixed methods process evaluation embedded in a randomised controlled trial.BACKGROUND
 A randomised trial of European Fans in Training (EuroFIT), a 12-week healthy lifestyle program delivered in 15 professional football clubs in the Netherlands, Norway, Portugal, and the United Kingdom, successfully increased physical activity and improved diet but did not reduce sedentary time.  1) how was EuroFIT implemented?  We analysed qualitative data implementation notes, observations of 29 of 180 weekly EuroFIT deliveries, semi-structured interviews with 16 coaches and 15 club representatives, and 30 focus group discussions with participants (15 post-program and 15 after 12 months).  We successfully recruited clubs, coaches and men to EuroFIT though the draw of the football club seemed stronger in the UK and Portugal.  Advertising that emphasized getting fitter, club-based deliveries, and not 'standing out' worked and attendance and fidelity were good, so that coaches in all countries were able to deliver EuroFIT flexibly as intended.  EuroFIT was delivered as planned by trained club coaches working flexibly in all countries. 
EuroFIT