Physical activity interventions differentially affect exercise task and barrier self-efficacy: a meta-analysis
Health Psychology (2014) - Comment
pubmed: 23957904  doi: 10.1037/a0033864  issn: 1930-7810  issn: 0278-6133 

Torrance J. Higgins, Kathryn R. Middleton, Larry Winner, Christopher M. Janelle