title: Behavioral impacts of sequentially versus simultaneously delivered dietary plus physical activity interventions: the CALM trial.
abstract: BACKGROUND
  Few studies have evaluated how to combine dietary and physical activity (PA) interventions to enhance adherence.
  
  
  OBJECTIVE
  We tested how sequential versus simultaneous diet plus PA interventions affected behavior changes.
  
  
  METHODS
  Two hundred participants over age 44 years not meeting national PA and dietary recommendations (daily fruit and vegetable servings and percent of calories from saturated fat) were randomized to one of four 12-month telephone interventions: sequential (exercise first or diet first), simultaneous, or attention control. At 4 months, the other health behavior was added in the sequential arms.
  
  
  RESULTS
  Ninety-three percent of participants were retained through 12 months. At 4 months, only exercise first improved PA, and only the simultaneous and diet-first interventions improved dietary variables. At 12 months, mean levels of all behaviors in the simultaneous arm met recommendations, though not in the exercise- and diet-first arms.
  
  
  CONCLUSIONS
  We observed a possible behavioral suppression effect of early dietary intervention on PA that merits investigation.
authors.affiliation: Department of Health Research & Policy and Stanford Prevention Research Center, Department of Medicine, Stanford University School of Medicine, Stanford, CA, USA, king@stanford.edu.
authors.forename: Abby C
authors.initials: AC
authors.lastname: King
authors.forename: Cynthia M
authors.initials: CM
authors.lastname: Castro
authors.forename: Matthew P
authors.initials: MP
authors.lastname: Buman
authors.forename: Eric B
authors.initials: EB
authors.lastname: Hekler
authors.forename: Guido G
authors.initials: GG
authors.lastname: Urizar
authors.forename: David K
authors.initials: DK
authors.lastname: Ahn
mesh_terms: D004032:Diet; D015444:Exercise; D005260:Female; D015438:Health Behavior; D006293:Health Promotion / Q000379:methods*; D006801:Humans; D008297:Male; D008875:Middle Aged; D009043:Motor Activity; D009751:Nutritional Requirements; D010349:Patient Compliance / Q000523:psychology*