title: The effect of need supportive text messages on motivation and physical activity behaviour.
abstract: Few short messaging service (SMS) studies to support behaviour change have used a theoretical underpinning. Using a self-determination theory perspective, we explored the effects of need supportive (NS) SMS on physical activity in 65 (BMI = 24.06 kg/m(2), SD = 5.49; M = 25.76 years, SD = 10.23) insufficiently active individuals embarking on an existing exercise programme. For 10 weeks participants were randomised to an intervention group (NS) or control group (neutral). SMS were sent twice weekly, randomly, via an online SMS service. Mixed design ANCOVA and MANCOVA analyses of measures taken at baseline, mid and post intervention revealed increased levels of perceived autonomy support and psychological need satisfaction in the intervention group post intervention. Both groups reported increases in intrinsic motivation from pre to post intervention. Moderate intensity physical activity was greater in the intervention than the control group at 4-month post intervention with control group returning to baseline levels. Findings provide preliminary causal evidence to support the use of NS SMS to optimise physical activity behaviour change in individuals who are insufficiently active.
authors.affiliation: Institute of Health and Well-being, University of Northampton, Northampton, NN2 7AL, UK. florence.kinnafick@northampton.ac.uk.
authors.forename: Florence-Emilie
authors.initials: FE
authors.lastname: Kinnafick
authors.affiliation: School of Psychology and Speech Pathology, Curtin University, Bentley, WA, 6102, Australia.
authors.forename: Cecilie
authors.initials: C
authors.lastname: Thøgersen-Ntoumani
authors.affiliation: School of Sport, Exercise and Rehabilitation Sciences, University of Birmingham, Birmingham, B15 2TT, UK.
authors.forename: Joan
authors.initials: J
authors.lastname: Duda
mesh_terms: D000328:Adult; D015444:Exercise / Q000523:psychology*; D005260:Female; D015438:Health Behavior; D006801:Humans; D008297:Male; D009042:Motivation; D026684:Personal Autonomy; D010549:Personal Satisfaction; D012944:Social Support; D060145:Text Messaging
keywords: Exercise class; Intervention; Need support; SMS; Self-determination theory