Abstract
Research suggests we need to increase physical activity (PA) as well as reduce sedentary behaviour (SB) to benefit health (Janssen et al., 2020). Normative messages were shown to alter both PA and SB in one study (Priebe & Spink, 2015), while in another, only SB changed (Anderson et al., 2022). Both studies used a normative message that combined PA and SB behaviours. To date, no studies have examined the effects of single versus combined behaviour messaging. This would be instructive, as single versus combined messages may generate different outcomes (Vandelanotte et al., 2005). This study investigated whether exposure to single or combined normative messages would influence on-campus PA or SB intentions. In an online survey, participants (N=129) were randomly assigned to receive one of four normative messages: activity, sedentary, combined activity and sedentary, or attention control. Following message receipt, participants reported future on-campus PA and SB intentions. Following an omnibus MANOVA condition effect (p=0.007), post hoc tests revealed that the messages significantly impacted both PA (p=0.014) and SB (p=0.003) intentions. For PA intentions, only those receiving the activity message reported greater intentions versus control (p=0.014). However, with respect to intention to decrease SB, those receiving the activity (p=0.008), sedentary (p=0.015), or combined (p=0.024) normative message all reported stronger intentions to reduce SB while on campus versus those receiving the control message. This provides initial evidence that single versus combined normative behaviour messages may result in different PA and SB outcomes depending on the behaviour targeted in the message.
