Annals of Behavioral Medicine

, Volume 49, Issue 2, pp 286–292 | Cite as

Behavioral Mediators of Weight Loss in the SHED-IT Community Randomized Controlled Trial for Overweight and Obese Men

  • Myles D. Young
  • David R. Lubans
  • Clare E. Collins
  • Robin Callister
  • Ronald C. Plotnikoff
  • Philip J. Morgan
Brief Report



Little is known about which behavioral strategies are most important to target in weight loss interventions for men.


The aim of the current study was to identify behavioral mediators of weight loss in the male-only Self-Help, Exercise, and Diet using Information Technology (SHED-IT) community weight loss study.


A randomized controlled trial with 159 overweight/obese men [mean (SD) age = 47.5 (11.0) years; body mass index = 32.7 (3.5) kg/m2] assessed at baseline, 3 months (post-test) and 6 months (follow-up).


In an intention-to-treat, multiple-mediator model, the significant intervention effect on weight at 6 months (−3.70 kg; p < 0.001) was mediated by increases in physical activity (steps/day) and decreases in takeaway meals (kJ/day) and portion size at 3 months. The largest mediation effect was for physical activity (−0.6 kg; 95 % confidence interval −1.4, −0.1). Overall, the targeted mediators accounted for 47.0 % of the intervention’s effect on weight.


Step counts, takeaway food consumption, and portion sizes may be key areas to target in future weight loss programs for men (ACTRN12610000699066).

Supplementary material

12160_2014_9657_MOESM1_ESM.doc (97 kb)
ESM 1(DOC 97 kb)


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Copyright information

© The Society of Behavioral Medicine 2014

Authors and Affiliations

  • Myles D. Young
    • 1
  • David R. Lubans
    • 1
  • Clare E. Collins
    • 2
  • Robin Callister
    • 3
  • Ronald C. Plotnikoff
    • 1
  • Philip J. Morgan
    • 1
  1. 1.Priority Research Centre in Physical Activity and Nutrition, School of Education, Faculty of Education and ArtsUniversity of NewcastleCallaghanAustralia
  2. 2.Priority Research Centre in Physical Activity and Nutrition, School of Health Sciences, Faculty of Health and MedicineUniversity of NewcastleCallaghanAustralia
  3. 3.Priority Research Centre in Physical Activity and Nutrition, School of Biomedical Sciences and Pharmacy, Faculty of Health and MedicineUniversity of NewcastleCallaghanAustralia

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