Table 1. Description of researchers' primary role in trial conduct and mechanisms for blinding.

Description of researcher(s)	1° role in trial conduct	Mechanism(s) to ensure blinding
Exercise physiologists supervising exercise interventions, including supervision of exercise group leaders (ND and HM)	Administer and monitor exercise interventions and measure adherence to prescribed exercise, including heart rate response to exercise	Following participant randomization, researchers excluded from data collection, other than recording exercise attendance and heart rate. Downloaded heart rate data not analyzed until intervention completed.
Exercise physiologists undertaking VO2max tests (GB, MH, JS, NK)	Responsible for VO2max testing at exercise laboratory and collection of raw data	Blind to group allocation
Exercise physiologist responsible for calculation of VO2max i.e. primary endpoint (JC)	VO2max calculation using raw data forwarded electronically from the exercise laboratory	Blind to participant identity and to group allocation and working at a remote site. Calculated VO2max results forwarded electronically to biostatistician at baseline and at follow up. Following calculation of baseline VO2max, researcher had no further access to these baseline data
Physician (HL)	Documentation of harms/adverse events	Blind to group allocation. Harms documentation locked with biostatistician after completion of exit interview
Research nurses (led by FL)	Collection of laboratory and pedometer data (used to measure non prescribed incidental activity)	Blind to group allocation
Dietitian	Interview participants about food records, analyze macronutrient intake	Blind to group allocation