Exercise promotion on Instagram
Do influencers have more impact to change people’s attitude and intentions towards exercise compared to famous athletes?
Sanne Knulst – 11068426 University of Amsterdam
Graduate school of Communication
Master’s programme Communication Science Supervisor: Birthe Andrea Lehmann
Word count: 7.491 25-06-2020
Abstract
Nowadays there are still too many people that do not exercise on a regular basis, despite the reduction of health-related risks. The purpose of this study is to test whether differences between source type (influencer versus athlete) of an Instagram post promoting physical activity, source credibility, self-efficacy and gender affects attitude and intention towards exercise. The influence of source type, the possible mediating effect of source credibility and self-efficacy, and the possible interaction effect of gender of the participants and source, on attitude and intentions of 233 adults has been examined. Source type did not cause any differences in attitude and intention towards exercise. But the higher the self-efficacy the more positive the attitude and intentions towards exercise were. For source credibility opposite effects were found. When the message came from an influencer this has a negative impact on expertise and trustworthiness. When attractiveness and expertise were perceived high this has a positive effect on attitude. The effect of source type on attitude is mediated by expertise. Self-efficacy and the dimension expertise of source-credibility both can be used in the development of persuasive messages to promote physical activity. More research needs to be done to expand scientific literature about the promotion of exercise on Instagram and to provide better practical implications.
Introduction
Nowadays it is common knowledge that physical inactivity involves all kinds of health-related risks. The evidence that physical activity can contribute to your health is overwhelming. It is stated that almost everyone can benefit from becoming physically active (Warburton & Bredin, 2016). Physical inactivity is a changeable risk factor for cardiovascular diseases, a lot of other chronic diseases (e.g. cancer, obesity, diabetes and depression) and even mortality (Blair & Brodney, 1999; Blair, Cheng & Holder. 2001; Kohl, 2001; Manson et al., 2002; Myers, Froelicher, Do, Partington, & Atwood, 2002; Warbutron, Nicol & Bredin, 2006).
According to a study carried out by the European Commission on sport and physical activity, the number of Europeans exercising on a regular basis, despite an increase, is very low. Nearly half of Europeans say that they never exercise or play a sport (European
Commission, 2018). Because of the health benefits and the low number of people who engage in physical activity, it still very important to promote physical activity. Government
institutions, health organizations, health experts and scientists expose individuals to many campaigns to persuade and motivate people to engage in physical activity on a regular basis. But are these campaigns effective? And are these campaigns based on empirical studies? Social media has become an integral part of everyday life. In this regard, it is impossible to imagine a world without the so-called influencers. The question arises how social media can be used when motivating people to exercise? Can one source be better used than another?
The effectiveness of celebrity (including athletes) endorsement is widely investigated, but mainly in the marketing research field (Chung & Cho, 2017; Erdogan, 1999; Lee & Koo, 2015; Pradhan, Duraipandian, & Sethi, 2016). There is also a lot of research done about athletes and their impact as role models (Armour & Duncombe, 2012; Biskup & Pfister, 1999; Brown, Basil, & Bocarnea, 2003; Jones, 2011; Lines, 2001; Martin & Bush 2000). But,
despite the growth in number of influencers, scientific research on their effect to increase physical activity is limited. Scientific knowledge about the overall impact of influencers is understudied. Another aspect that is widely investigated is inspirational fitness (fitspiration) images on social network sites and the impact on viewers (Robinson, Prichard, Nikolaidis, Drummond, Drummond, & Tiggemann, 2017; Slater, Varsani, & Diedrichs, 2017; Tiggemann & Zaccardo, 2018). Fitspiration is an online trend to inspire recipients for a healthier lifestyle by promoting exercise and eating healthy food (Tiggemann & Zaccordo, 2018). Social media provides opportunities to promote physical activity and can be an important tool to change behaviour. There can be a gap identified in research, because little research is done about the differences between sources, a famous athlete and an (non-athlete) influencer, and its impact on physical activity.
A possible solution to promote exercise could be Instagram posts promoting exercise by influencers. Most influencers on social media are women (Schouten, Janssen, &
Verspaget, 2020). This could have an impact on the persuasiveness of the message, which is why gender is included in this study. The present study investigates the impact of famous athletes versus influencer Instagram posts promoting physical activity on the effectiveness of the message posted on Instagram (attitude and behaviour intention), moderated by gender. Thus, the following research question has been formulated: Do posts of an (non-athlete) influencer on Instagram persuading people to exercise have a more positive influence on attitude and intention towards physical activity, compared to posts by a famous athlete? Do women respond differently than men?
The dependent variables in this study are attitude and intention towards physical activity. According to Caspersen, Powell and Christenson (1985) refers physical activity to
occupational, sports, conditioning, household, or other activities and exercise is a component of physical activity. It is planned, repetitive and structured. In this study referring to physical
activity, the subset exercise is meant. Exercise behaviour can be defined as exercising for at least 20 minutes, three times per week for the next three months (Terry & O’Leary, 1995).
Any differences in impact of the source, a famous athlete or an influencer, are examined. Kaplan and Haenlein (2010) defined social media as “a group of Internet-based applications that build on the ideological and technological foundations of Web 2.0, and that allow the creation and exchange of User Generated Content”. Instagram is an online mobile phone, image and video sharing social network service (Frommer, 2010). The growth of this platform continues. According to the Nationale Social Media report of Newcom Research & Consultancy B.V. (2020), Instagram is one of the fastest growing social media platforms. For this reason, this research will investigate Instagram as social media platform.
There are several key variables incorporated in this study, e.g. self-efficacy and source credibility. Gender is another key variable that also could have an impact on attitude and intention. Several studies mention that females and males respond differently when evaluating messages of the opposite sex (Peetz, Parks, & Spencer,2004; Popcorn & Marigold, 2000).
It is important that this research is done for a number of reasons. First of all, this research can provide more evidence for pre-existing behavioural change theories. Second, it is very important that physical activity continues to be promoted, because there are still too many people that do not exercise on a regular basis, while it has been proven to reduce health risks. It can also be examined to what extend a match between gender (source and participant) has an impact on source credibility. It can provide new insights in the effectiveness of the use of influencers to change health behaviour. Finally, the business community and government can benefit from the results of this study with regard to their persuasive messages. They can put the results of the empirical study into practice, and apply them to the development of persuasive messages to promote physical activity.
Theoretical Framework
There are many behavioural theories that help develop empirical driven exercise interventions. For example, the Theory of Planned Behavior and the Social Cognitive Theory. In addition, there are models widely used in marketing research, like the Elaboration
Likelihood model that could be relevant when developing an intervention to motivate people to exercise.
There are a couple of theories widely used for health behaviour change. One of these theories is the Theory of Planned Behavior (TPB) of Ajzen (1991), an extension of the Theory of Reasoned Action. A theory designed to predict and explain human behaviour. It states that human behaviour is guided by three different kind of beliefs: behavioural beliefs, normative beliefs and control beliefs. Behavioural beliefs are beliefs about the consequences of a certain behaviour. Attitude towards the behaviour emerges from these beliefs. Normative beliefs refer to beliefs about the normative expectations of others. These beliefs produce perceived social pressure or a subjective norm. Control beliefs refer to the beliefs about the presence of factors which may facilitate or interfere with the performance of a certain behaviour. Control beliefs provide the basis for perceptions of self-efficacy or perceived behavioral control. Perceived behavioural control is an important aspect of health behavioural change. It is comparable to the concept of the perception of self-efficacy of Bandura (1982). It refers to people’s perception of ease or difficulty to perform a certain behaviour. Intention is assumed to be a predictor of behaviour (Ajzen, 1999). Poobalan, Aucott, Clarke, and Smith (2012)
investigated physical activity attitudes and intentions. They based their design on health behaviour change theories, such as TPB and the Social Cognitive Theory. They found evidence that positive attitudes towards physical activity were strong predictors of exercise behaviour. In this study attitude refers to positive or negative feelings of the participants towards the exercise behaviour. It refers to the overall evaluation of physical activity (Ajzen
& Fishbein, 1977). Intention to exercise concerns the extent to which the participant is inclined to change their behaviour to exercise. It is about the motivation of someone to
perform a certain behaviour. It is an indication of how hard people al willing to try, in order to perform the behaviour (Ajzen, 1991). Differences between the source will be examined. The source is a famous athlete, when the person of interest is seen as a celebrity due to the achievements in the sport they practice. Djafarova and Rushworth (2017) showed with their research that non-traditional celebrities, such as influencers on Instagram have a bigger impact on purchase behaviour, compared to more traditional celebrities. Schouten, Janssen, and Verspaget (2020) found evidence in their marketing research that influencers are more effective product endorsers than celebrities, such as athletes. A social media influencer is someone who has gained fame by personal branding. They successfully developed a
distinctive public image and they are seen as experts on social media platforms (Khamis, Ang & Welling, 2016). Therefore, the expectation of this study is that influencers will have a greater impact on attitude and intention towards physical activity. The research question will be answered by testing several hypotheses. The first hypothesis concerns the main effect of exposure to an Instagram post of an influencer versus an athlete: Exposure to an Instagram post promoting physical activity of an influencer will lead to a more positive attitude and intention towards physical activity than exposure to an Instagram post of a famous athlete.
Another theory connected to physical activity and available to assist the development of persuasive communications is the Social Cognitive Theory of Bandura (1989). The theory states that learning occurs in a social context. It is related to many health practices. The key determinants include benefits and risks of health practices, perceived self-efficacy, outcome expectancies of the behaviour (exercise), health goals people set, plans to realize these goals and social or structural factors that can influence the behaviour of interest (Bandura, 2004). For example, if people lack knowledge about how exercise can positively affect their health,
they have little reason to change their behaviour. The outcome of a specific health behaviour can also determine whether people are willing to exercise, for example do they think it will positively affect their state of mind? The purpose of social cognitive theory is to give an explanation of how people regulate their behaviour through control and reinforcement to achieve a certain behaviour that can be maintained over time (Bandura, 1989). Another important determinant of health behaviour is self-efficacy. This concept can be defined as the confidence in ability to perform a certain behaviour and is strongly related to the actual ability to perform this behaviour. Self-efficacy affects health behaviour both directly and indirectly through the other determinants (Bandura, 2004). Self-efficacy beliefs are closely related to the performance of exercise behaviour and function as determinants of human motivation.
Marcus, Selby, Niaura and Rossi (1992) demonstrated with their research that self-efficacy is significantly related to different stages of change process of exercise. Terry and O’Leary (1995) found evidence that self-efficacy predicted intentions. Maintaining or adopting exercise depends to a great extent on self-efficacy beliefs of individuals. People with high self-efficacy are more likely to change their exercise behaviour (Kroll, Kehn, Ho & Groah, 2007). Celebrities can serve as role models, they can serve as a motivator to start exercising, and therefore increase self-efficacy (Martin & Bush, 2000). Influencers are more perceived as ordinary persons, compared to traditional celebrities, such as famous athletes. People have a bigger urge to behave the same and possess the same as the influencers, because it seems more attainable and feasible (Jin, Maqaddam & Ryu, 2019). People are better able to relate to influencers than more traditional celebrities (Djafarova & Rushworth, 2017), this has a positive impact on their efficacy (Lin, Hung & Chen, 2009). Due to these findings, self-efficacy beliefs will be incorporate into this research as a mediator. The next hypothesis targets the effect of self-efficacy: Exposure to an Instagram post promoting physical activity of an influencer will lead to a more positive attitude and intention towards physical activity
than exposure to an Instagram post of a famous athlete, and this effect is mediated by self-efficacy.
The Elaboration Likelihood Model (ELM) is a popular model for the investigation of attitude development. It is a dual process theory that describes how attitudes can be developed and changed. It describes the processes underlying the effectiveness of persuasive messages (Petty & Cacioppo, 1986). The model explains different ways of processing stimuli, why they are used, and what impact they have on attitude change. There are two routes of information processing to attitude change; the central route and the peripheral route. The central route is used, when the ability and the motivation of the recipient of the message are high; the information will be evaluated more thoroughly. In contrast, when the ability and motivation of the recipient are low, the message will be evaluated based on simple assumptions, i.e. peripheral cues. An example of a peripheral cue is source credibility. Source credibility is also widely investigated in the field of exercise promotion (Arora, Stoner & Arora, 2006; Berry & Shields, 2013; Jones, Sinclair & Courneya, 2003). Source credibility is described by Ohanian (1990) as the positive characteristics of communicators that have influence on recipient’s acceptance of the message. It consists of three dimensions; trustworthiness, expertise and attractiveness. This study uses the definition given by Ohanian (1990). Trustworthiness refers to the perceived honesty, integrity, and objectivity of the celebrity (Erdogan, 1999).
Goldsmith et al. (2000) concluded in their research that when someone is perceived as trustworthy, this has a positive effect on persuading consumers. Expertise refers to the knowledge, experience or skills of the celebrity. The celebrity does not have to be an expert, but the recipients must have the perception that he or she is an expert (Ohanian, 1999). Attractiveness refers also to other characteristics than to the physical appearance, such as: lifestyle, athletic performance, intellectual and personal skills (Erdogan, 1999).
When these three dimensions of the source are perceived as high, it will have a positive effect on attitude towards the message of the source, compared to a source perceived as
non-credible. Previous research showed that messages from non-traditional celebrities such as social media influencers were perceived as more credible, compared to more traditional celebrities such as athletes (Djafarova & Rushworth, 2016; Schouten, Janssen, & Verspaget, 2020). The third hypotheses targeted the effect of source credibility: Exposure to an
Instagram post promoting physical activity of an influencer will lead to a more positive attitude and intention towards physical activity than exposure to an Instagram post of a famous athlete, and this effect is mediated by source credibility.
Besides source credibility, gender is a determinant factor in the effectiveness of a persuasive message. Men and women process messages differently (Meyers-Levy & Maheswaran, 1991). Females engage in more detailed information processing; they tend to elaborate the message content comprehensively. Males limit cognitive effort and therefore use more heuristic processing, by focussing more on cues. Popcorn and Marigold (2000)
additionally found that women respond more positively to a female imagery, while men respond more positively to images of males. The study of Peetz, Parks and Spencer (2004) showed that the recipients saw male athletes as more credible compared to female athletes. Men were more likely to be influenced by male athletes. Djafarova and Rushworth (2017) have found evidence that female influencers have a bigger impact on females. Building on these studies, this study expected the impact to be stronger when the gender of source and participant is matched. According to previous research (Djafarova and Rushworth, 2017; Wilcox & Stephen, 2013) are females more susceptible to social influence and more likely to influenced by celebrities. Therefore, it is expected that the impact of the influencer conditions on females is bigger than on males. For this reason, it can be concluded that gender, of both source and recipient, has an impact on the persuasiveness of messages. In this study the
gender of the source is manipulated. The following hypotheses concerned the difference in response between men and women to the gender of the source: The impact of exposure to an Instagram post promoting physical activity on source credibility is bigger when the post comes from the same gender as the participants, compared to a different gender. The final hypothesis targets the gender differences: Exposure to an Instagram post promoting physical activity of an influencer will lead to a more positive attitude and intention towards physical activity than exposure to an Instagram post of a famous athlete, and this has a bigger impact on women compared to men. See Figure 1 for a conceptual model of the hypotheses.
Figure 1. Conceptual Model
Method Research Design and Stimuli
To answer the research question and test the hypotheses an empirical experiment was conducted. The choice for an experiment was the most obvious one for this research, because it made it possible to look clearly at how people react to different stimuli. In this way, the causal relationships of the source and gender on the dependent variables attitude and
intentions towards exercise could be clearly demonstrated. The experimental design of this study is a between subjects 2 (source: famous athlete versus influencer) x 2 (gender source: woman versus man) x 2 (gender participants: male versus female) factorial design. The source of the Instagram post has two levels: an Instagram post posted by a famous athlete and an Instagram post posted by an influencer. The gender of the source has two levels: male versus female. The source type and gender of the source are manipulated. The famous athletes are professional tennis players. Maria Sharapova for the female condition and Rafael Nadal for the male condition. The female influencer condition is Claire Rose Cliteur and the male influencer condition is Justin Bieber. The materials are images of the athletes and influencers holding a tennis racket. The message promoting physical activity of the posts is the same in all conditions. The caption below the image is: ‘Be active your way! Pick an activity you like, one that fits into your life. I love playing tennis, what kind of exercise do you like most? #beactiveyourway’ (see Appendix A for the stimuli). The gender of the participants cannot be manipulated, thus is tested at the beginning of the questionnaire. The construction of the research design is schematically demonstrated in the table below (Table 1).
Table 1
Design diagram of Experimental Design Experimental Variable Athlete Influencer Gender source: Male Gender source: Female Gender source: Male Gender source: Female Gender participant: Male 25 28 25 28 Gender participant: Female 32 31 34 30
Sample
The main inclusion criterion for the study was that the participants had to be between 18 and 33 years of age, to capture the so-called ‘net generation’ (Voorveld & van der Goot, 2013). The participants had to indicate their gender and age at the beginning of the
questionnaire. For this study 304 people agreed to participate. Twenty-nine participants had to be excluded because they indicated not meeting the criterion of the age between 18-33 years old. Another 42 additional participants stopped participating early in the study. These participants were removed from the dataset due to missing values. Analyses were, thus, conducted over a sample of 233 participants in total (see Table 1 for the distribution of participants across cells). The mean age of the participants was 25.21 (SD = 2.85, range 18 to 33), 106 participants were male, and 127 were female. The participants were almost all highly educated (n = 200); they completed a bachelor’s degree or higher. The number of participants with the required characteristics are a valid choice in light of the research question.
Procedure
The participants were recruited via an anonymous link, that was distributed via social network applications, such as WhatsApp, Facebook and LinkedIn. After signing the informed consent, the participants had to answer some demographic questions. Afterwards, they were exposed to different Instagram posts promoting exercise. The participants were randomly assigned to one of the four conditions. After being exposed to the Instagram post, they could click through to the questionnaire (see Appendix B). They had to answer questions about source credibility, self-efficacy, attitude and intentions. At the end they had to answer a recall question. The last question was the manipulation question. After completing the
questionnaire, the participants were thanked for their participation. The participants had the right to stop the questionnaire at any time and were not obliged to do anything.
Instruments
There are two dependent variables measured in this study. One of these variables is attitude towards exercise. Attitude towards exercise is measured using the scale of González, Lópex, Marcos, and Rodríguez-Marín (2012). They have developed an instrument (based on different sources) to measure different variables included in the Theory of Planned Behavior in a context of physical activity. There are seven items to measure attitude: ‘For me, to exercise at least 20 minutes, three times per week for the next three months would be: very bad/very good, etc. (see Appendix B for all items). A principal component factoring analysis with the seven items measuring attitude towards exercise with Varimax rotation was
conducted. The analysis showed a one-dimensional construct (EV = 4.65) and the factor explained 66.46% of the variance. The seven items form a reliable scale (α = .91). To construct the variable Attitude, the items were computed using mean scores (M = 5.71, SD = 1.06).
Another dependent variable is intention. Intention towards exercise is also measured using the scale of González et al. (2012). They developed four items to measure intentions. The first item is: ‘I have thought about exercising three times a week at least 20 minutes for the next three months’: rated from 1 (strongly disagree) to 7 (strongly agree). For the other three items see Appendix B. A principal component factoring analysis with the three items measuring Intentions with Varimax rotation is conducted. The analysis showed a
one-dimensional construct (EV = 3.33) and the factor explained 83.21% of the variance. The three items form a reliable scale (α = .93). To construct the variable Intention, the items were computed using mean scores (M = 5.45, SD = 1.38).
There are a couple of independent variables measured in this study. Source credibility is measured using the scale of Ohanian (1990). This is a fifteen-item, 7-point semantic scale and contained three dimensions: Attractiveness (attractive/unattractive; stylish/not stylish;
handsome/ ugly; elegant/plain; sexy/not sexy), Trustworthiness (dependable/undependable; honest/dishonest; reliable/unreliable; sincere/insincere; trustworthy/untrustworthy) and Expertise (expert/ not an expert; experienced/inexperienced; knowledgeable/
unknowledgeable; qualified/unqualified; skilled/unskilled). First, a principal component factoring analysis with fifteen items testing source credibility with Varimax rotation was conducted. The factors had to have a minimum Eigenvalue of 1. The analysis showed a three-dimensional construct, and the factors explained 80.99% of the variance. The first component Attractiveness (EV = 7.94), consisting of five items, forms a reliable scale (α = .92).
Therefore, the variable Attractiveness was constructed (M = 5.21, SD = 1.20). The second component Trustworthiness (EV = 2.85), also consisting of five items, forms a reliable scale (α = .94). The variable Trustworthiness was constructed (M =4.71, SD = 1.35). The last component Expertise (EV = 1.36) also forms a reliable scale (α = .96). For the construction of Expertise the last five items were computed using mean scores (M =4.69, SD = 1.59).
Another independent variable, measured with three items, was self-efficacy. These items were adapted from previous research and were found to be a reliable scale (Armitage & Conner, 1999; Rhodes & Courneya, 2003). The first item of the scale is: ‘How confident are you that you will be able to exercise regularly in the next 2 weeks?’; rated on a 7-point scale from 1 (very unconfident) to 7 (very confident). For the other items of the scale see Appendix B. A principal component factoring analysis with the three items measuring Self-efficacy with Varimax rotation is conducted. The analysis showed a one-dimensional construct (EV = 2.42) and the factor explained 80.79% of the variance. The three items form a reliable scale (α = .88). To construct the variable Self-efficacy, the items were computed using mean scores (M = 5.37, SD = 1.41).
To test the effectiveness of the manipulation two independent samples t-tests were conducted with 10 recipients per condition in a pre-test. The manipulation check was
measured with the following question about the source credibility: ‘On a scale from 1 to 10 to what extent do you feel the source was credible?’: rated from 1 (not credible) to 10 (very credible). The analysis showed no significant difference between the male athlete (M = 6.9, SD = 1.45) and male influencer condition (M = 7.1, SD = 1.73), t(18) = .280, p = .782. So, for the male conditions, there is no significant effect. The t-test for the female conditions did show a significant effect. There was a significant difference between the female athlete (M = 5.3, SD = 1.42) and female influencer condition (M = 6.8, SD = 1.56), t(18) = 2.254, p < 0.05. Participants in the female influencer condition indicated that the source was more credible than participants in the female athlete condition. Thus, the manipulation of the female condition is effective. Since the actual study included enough participants to have a good statistical power, this effect was also expected for the male conditions.
Results
This section shows the results of the tested hypotheses that have been drawn up, that together will answer the research question of this study.
Control variables
In order to check if participant characteristics were equally distributed across conditions, a randomization check has been conducted. An ANOVA analysis, with the dependent variable age and the conditions as the independent variable, showed no significant effect, F(3,229) = 1.920, p =0.127), η2 = .03. Therefore, it can be concluded that random assignment into conditions on this variable was successful.
In order to check whether gender and education of the participants could have an effect on the dependent variables Chi-square tests were conducted. The Chi-square test showed no significant difference for gender X2(3) = .566, p = .904. The Chi-square test for education also showed no significant effect X2(12) = 7.709, p = .804. This indicated that there
were no differences between conditions on gender and level of education. Based on these analyses we can assume that randomization was successful.
Manipulation check
At the end of the questionnaire the participants have answered a question about the manipulation, the perceived credibility of the source. Participants had to indicate how credible they perceived the source, on a scale from 1-10. To determine the effectiveness of the
manipulation, two independent samples t-tests were conducted. The analysis showed
significant differences between the female athlete condition (M = 7.41, SD = 2.09) and female influencer condition (M = 5.22, SD = 2.39), with regard to perceived credibility of the source, t(115) = 5.273, p < .001. In contrast to the pre-test, the manipulation check between the male athlete condition (M = 7.58, SD = 1.82) and the male influencer condition (M = 6.17, SD = 2.18) showed a significant effect, t(114) = 3.769, p < .001. Both t-tests indicated a significant difference, but not the way it was expected. The athlete conditions scored significantly higher on perceived credibility compared to the influencer conditions. Thus, the manipulation did have an effect, but in a different direction than hypothesized.
Hypotheses testing
To test the first hypothesis, independent samples t-tests were conducted, with attitude and intention as the dependent variables and source type (influencer versus athlete) as
independent variable. The conditions of both male athlete and female athletes were combined, and the conditions of male influencer and female influencer were combined computing mean scores. The analysis indicated that the average attitude towards exercise in the influencer conditions (M = 5.75 SD = 1.00) did not differ significantly from the attitude in the athlete conditions (M = 5.67, SD = 1.13), t(231) = -.518, p = .605. The independent samples t-test also indicated that the average intention towards exercise in the influencer conditions (M = 5.40, SD = 1.34) did not differ significantly from the intention in the athlete conditions (M =
5.28, SD = 1.45), t(231) = -.194, p = .054 (see Table 2 for an overview). Thus, Hypothesis 1 is rejected.
Table 2
Distribution of the participants across conditions and means and SDs for attitude and intention towards exercise.
Conditions n Gender m/f Attitude M SD Intentions M SD Athlete 116 53/63 5.67 1.13 5.28 1.45 Influencer 117 53/64 5.75 1.00 5.40 1.34
In order to test H2 and H3 mediation analyses, based on the traditional approach of Baron and Kenny (1986), were conducted. To test the second hypothesis about the mediating role of self-efficacy, regression analyses were conducted. The first regression analysis, with self-efficacy as dependent variable and source type as independent variable showed no significant effect, b = .048, t = 0.261, p = .794, 95% CI [-0.316, 0.413]. Source type was coded as 0 = athlete and 1 = influencer. The second model with attitude as dependent variable and source type and self-efficacy as independent variables, was significant F(2,230) = 33.060, p < .001. The model can be used to predict the attitude towards exercise, but the prediction is moderate in strength R2 = .22. Self-efficacy has a significant moderately strong correlation with attitude, b= .356, t = 8.11, p < .001, 95% CI [0.270, 0.443]. When self-efficacy
increases, the attitude towards exercise is more positive. But, the main effect of source type (influencer versus athlete) on attitude remains non-significant, b = .06, t = .447, p = .655, 95% CI [-0.188, 0.298]. To check if there was a significant mediation effect a Sobel’s test was conducted. The indirect effect is not significant, Z = 0.259, p = 0.795. To test the effect on intention a regression analysis is conducted. The second model was found significant, with
intention as dependent variable and source type and self-efficacy as independent variables, F(2,230) = 65.940, p < .001. The model showed that source type and self-efficacy were moderately strong predictors of intention, R2 = .36. Source type has a significant correlation with intention towards exercise, b = .320, t = 2.211, p = .0281, 95% CI [0.035, 0.606]. This means that influencer post predicts intention through self-efficacy. The correlation between self-efficacy and intentions was strong, b = .574, t = 11.15, p < .001, 95% CI [0.473, 0.676]. The indirect effect of source type on intention was not significant, Z = 0.26100948, p
0.7940852. The second hypothesis about the mediation effect of self-efficacy is rejected for the effect on attitude (See Figure 2). This study has also no evidence for the mediation effect on intentions towards exercise (See Figure 3).
* Significant values (p < .05)
Figure 2. Mediation effect self-efficacy between source type and attitude
* Significant values (p < .05)
It is examined whether there was a mediating effect of source credibility on source type and attitude and intention through regression analyses. Following the original study of Ohanian (1991), source credibility was measured through the three components:
attractiveness, trustworthiness and expertise. The effect of source type on attractiveness was not significant, b =.158, t = 1.005, p = .316, 95% CI [-.152, .468]. This means that influencer post has no effect on attractiveness. The regression analysis with trustworthiness as dependent variable was significant, F(1,231) = 12.620, p <.001, but the prediction was very weak R2 = .052. When the source of the Instagram post was an influencer the participants indicated that the source was significantly less trustworthy compared to the participants in the athlete
condition, b = -.610, t = -3.552, p <.001, 95% CI [-.949, -.272]. The analysis with expertise as dependent variable was also significant, F(1, 231) = 91.289, p <.001, but the prediction was weak R2 = .28. The participants in the influencer conditions indicated that the source was less perceived as an expert compared to the participants in the athlete conditions, b = 1.683, t = -9.555, p < .001, 95% CI [-2.030, -1.336]. The regression analysis with attitude as dependent variable, the three components of source credibility as mediators and source type as
independent variable was significant F(4,228) = 10.060, p <.001, but again the prediction was weak R2 = .15. The correlation between attractiveness and attitude towards exercise was significant, b =.208, t = 3.250, p = .001, 95% CI [0.082, 0.334]. The indirect effect of source type on attitude was not significant, Z = 0.50, p = 0.337. The correlation between expertise and attitude was also significant b = .142, t = 2.318, p = .021, 95% CI [0.021, 0.262]. The indirect effect of source type on attitude was significant, Z = -2.252, p = 0.024. But the correlation between trustworthiness and attitude was not significant b = .048, t = .715, p = .475, 95% CI [-0.085, 0.181]. The indirect effect of source type on attitude was also not significant, Z = -0.681, p = 0.496. There was no significant effect found for source type on attitude, b = .307, t = 1.926, p = .055, 95% CI [-0.007, 0.621. For an overview see Figure 3.
The same analyses were conducted with intention towards exercise as dependent variable. The regression analysis with intention as dependent variable, attractiveness, trustworthiness and expertise as mediators and source type as independent variable was not significant
F(4,229) = 1.231, p =.066. The three components of source credibility were all not significant (Attractiveness b =.058, t = .658, p = .511, 95% CI [-0.116, 0.232], trustworthiness: b =.039, t = .386, p = .700, 95% CI 0.148, 0.220], Expertise: b =.095, t = 1.122, p = .265, 95% CI [-0.071, 0.261]). There was a significant effect found for source type on intentions, b = .520, t = 2.370, p = .019, 95% CI [0.088, 0.953]. The third hypothesis about the mediation effect of source credibility on intention towards exercise is therefore not confirmed, but the mediation effect on attitude is partly confirmed.
* Significant values (p < .05)
Figure 3. Mediation effect of source credibility on attitude
The fourth hypothesis is tested by means of a multivariate ANOVA analysis with gender of the source and gender of the participants as independent variables and the source credibility components (attractiveness, trustworthiness and expertise) as dependent variables. The analyses were not significant (attractiveness: p =.516, trustworthiness: p = .757 and expertise: p = .189). Therefore, the fourth hypothesis is not confirmed. A match between the gender of the source and the gender of the participants has no significant impact on source credibility.
To test the fifth hypothesis a Univariate ANOVA was conducted, with attitude and intentions towards exercise as dependent variables and source type and gender of the
participants as independent variables. The results of the interaction effect between source type and gender of the participants showed no significant difference on attitude (F(1,229) = 0.035, p = 0.851) and intentions (F(1,229) = 0.017, p = 0.897). Therefore, the last hypothesis is not confirmed. The Instagram post of influencers have no bigger impact on women compared to men.
At the end of the questionnaire there was a recall question about the condition the participants were exposed to. The participants needed to answer the following question: ‘You were exposed to an Instagram post. What type of source did you see?’ With the answer options ‘I saw an Instagram post from a male athlete persuading me to exercise’/ ‘I saw an Instagram post from a male influencer persuading me to exercise’/ ‘I saw an Instagram post from a female athlete persuading me to exercise’/ ‘I saw an Instagram post from a female influencer persuading me to exercise’. 69 participants indicated that they were exposed to a post from a male athlete, but only 57 participants were actually assigned to that condition. 59 participants were assigned to the female athlete condition, and only 51 participants answered the recall question correct. Less participants than actually assigned to the male influencer condition (N = 58) indicated that they saw this condition (N = 51). More participants than assigned to the female influencer condition (N = 58) indicated that they saw the post of a female influencer (N = 61). It can be concluded that not all participants recalled the condition correctly. These participants were not excluded from this study, to not make the sample size smaller and have a good statistical power.
Conclusion and discussion
This study investigated the effect of source type, source credibility and self-efficacy on attitude and intention towards exercise. Based on the results of the conducted analyses the
following research question can be answered: Do posts of an (non-athlete) influencer on Instagram persuading people to exercise have a more positive influence on attitude and intention towards physical activity, compared to posts by a famous athlete? Do women respond differently than men? Based on a number of theories, an experiment was set up (N=233), consisting of four different conditions. With the results of this experiment a number of conclusions can be drawn with regard to gender, self-efficacy and credibility, the use of influencer or athlete sources, and the attitude and intentions towards physical activity. On top of that, practical implications for government institutions, health organizations and health experts developing messages promoting exercise of this study will be discussed.
First of all, the direct effect of different source types (influencer versus athlete) was examined. No difference has been found between the influencer conditions and the athlete conditions with regard to favourability of and motivation towards exercising.
Second, the role of self-efficacy was examined. Source type does not cause any difference for self-efficacy. There were no mediation effects of self-efficacy for attitude and intention. However, self-efficacy predicts both attitude and intention. The model with intentions as dependent variable showed that when the source of the message was an
influencer it increases intention. Previous research of self-efficacy and exercise indicated that self-efficacy is significantly related to maintaining or adopting exercise (Bandura, 2004, Kroll, Kehn, Ho, & Groah, 2007; Marcus, Selby, Niaura, & Rossi, 1992; Terry & O’Leary, 1995). Thus, this study confirms previous research and the Social Cognitive Theory. Evidence showed that self-efficacy has the ability to increase intention and attitude. Thus, self-efficacy should be used in interventions to change people’s exercise behaviour. Research needs to be done what aspects influences self-efficacy.
Furthermore, the role of source credibility was examined. Source credibility was tested by three components: attractiveness, trustworthiness, and expertise (Ohanian, 1990). Findings
showed that when the Instagram post is from an influencer, the source is perceived less credible compared to an Instagram post from an athlete, when it comes to trustworthiness and expertise. This is in contrast with findings of previous research of Djafarova and Rushworth (2017) and Schouten, Janssen, and Verspaget (2020). It could be that athletes are perceived more credible in a sport context compared to influencers, that is why this study found the opposite result. They found evidence that influencers are considered more credible than other celebrities when investigating advertising effectiveness. Findings of the current study showed that attractiveness and expertise predict attitude. Trustworthiness and expertise were indicated lower when the post came from an influencer. The mediation analyses showed only effect for the dimension expertise. Source credibility has no influence on intentions towards exercise. The Elaboration Likelihood model of Petty and Cacioppo (1986) described that when a peripheral cue as source credibility is perceived as high, this has a positive impact on the effectiveness of persuasive messages. The results of this study support this theory, but only for the impact of dimensions attractiveness and expertise on attitude. When developing an intervention, it is important that the source promoting exercise is perceived as an expert, such as an athlete.
A study of Peetz, Parks, and Spencer (2004) stated that recipients saw male athletes as more credible compared to female athletes, and that men were generally? more likely to be influenced by male athletes. Popcorn and Marigold (2000) found evidence that women respond more positively to a female imagery, while men respond more positively to male imagery. This study found no evidence to confirm previous research. Thus, a match between the gender of the source and participant does not contribute to an increase in perceived source credibility.
At last, it is examined whether the impact on attitude and intention is bigger for women in general. The results show no bigger impact on attitude and intention for women.
Previous research (Djafarova and Rushworth, 2017; Wilcox & Stephen, 2013) showed that women are more affected by social influences compared to men. Therefore, it was expected that the influence of a message promoting exercise on women would be bigger. This study has not been able to provide such evidence.
To answer the research question, posts of an (non-athlete) influencer on social media persuading people to exercise does not have a more positive influence on attitude and intention towards physical activity compared to posts of a famous athlete. Athletes have a positive effect on intentions and self-efficacy predicts intention. On top of that, the effect of source type on attitude was mediated by one dimension of source credibility, expertise. Moreover, men do not respond differently than women. Thus, it can be concluded that this study cannot provide evidence to support all the hypotheses.
An explanation for the absence of significant findings between source type (influencer versus athlete) and attitude and intention is that the sample includes few participants who are not highly educated. It could be that highly educated people evaluate dimensions as source credibility more thoroughly and therefore could perceive the source as less credible.
Another explanation could be that the participants were not exposed to the Instagram post in a natural environment and were aware that they were participating in a study. When exposed to the Instagram post in a natural environment, the processing of the message would take place more unconsciously. Now they had to evaluate their attitude and intentions more consciously. This can result in less extreme answers and consequently, missing significant results.
The way the conditions were manipulated could also be an explanation for the absence of significant findings. The four conditions were the same in all aspects except for the
manipulation: the type of source and gender. Participants could be not familiar with the source, or with type of sport (tennis). It could also be that the perceived difference between an
athlete and an influencer is not that big, and therefore the participants gave fewer extreme answers (e.g. not credible or very credible). Not all participants of this study recalled the conditions correctly, these findings showed that the perceived difference between the conditions was not clear for everybody. Nowadays, the concept influencer is hard to define. There are a lot of traditional celebrities that are now also famous through Instagram and are also so-called influencers. The distinction between influencers and more traditional celebrities is blurred. There is a fine line between influencers and athletes. This can be demonstrated by the results of the recall question. There were several participants that were not able to
distinguish the difference between conditions. This could have an impact on the results, or the absence of some results.
Last, source credibility was not something that changed the effect for intentions. But the manipulation check on source credibility was significant, which was measured differently than the main effects of source credibility. Athletes and influencers were both perceived as credible. It could be that athletes were perceived as credible based on their experience and knowledge of the specific sport, but the influencers were perceived as credible based on other aspects. Future research could pay more attention to the development of a persuasive message about physical activity.
Limitations and future research
Several limitations of this study need to be addressed. The first limitation is about the sample of the study. The sample includes over 80% highly educated participants (completed a bachelor’s degree or higher). This will likely limit the generalizability to a broader population of the findings. Future research should replicate the study, but conduct the experiment with a less homogeneous sample, such as including more participants who are less educated.
Another aspect of the sample of the study that could have limited the findings and its generalizability, is the relatively small sample size.
Second, the study focusses mainly on the influence of source type on attitude and intention. Future research should more closely examine other constructs that could affect participants’ attitude and intention to exercise on a regular basis, such as identification with the source, the reputation of the influencer and athlete and to what extent they already were physically active on a regular basis. More aspects of the message and participant could be taken into account.
A third limitation of this study is that there is no data collected about the exercise determinants before being exposed to the persuasive Instagram post promoting people to exercise on a regular basis. Measuring attitude and intentions prior to exposure to the stimuli could have showed whether attitude and intention were stable or might have been improved by both athlete and influencer conditions. Future research needs to address previous exercise behaviour determinants in order to draw better conclusions about the effectiveness of
persuasive messages promoting exercise on the attitude and intention change.
This study has contributed to existing scientific research and provides a set up for further research. Despite the evidence that physical activity contributes to health, nowadays the number of young adults exercising on a regular basis is still low. In order to change this and to use persuasive messages to change people’s exercise behaviour, more research needs to be done. For future research the manipulations must be adjusted, in order to draw better conclusions from the conducted analyses.
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Appendix A
Conditions
Female influencer
Male influencer
Appendix B
Questionnaire
Demographic questions 1. What is your gender?
o Male o Female
o Prefer not to say o Other (please specify): 2. What is your age?
o 18-22 o 23-27 o 28-33
3. What is the highest level of education you have completed? o Less than a high school diploma
o High school degree or equivalent o Bachelor’s degree (e.g. BA, BS) o Master’s degree (e.g. MS, MEd) o Doctorate (e.g. PhD, EdD) o Other (please specify):
The following questions are about the manipulation Source Credibility
Attractiveness
4. The source of the message is in my opinion: Attractive 0 0 0 0 0 0 0 Unattractive Stylish 0 0 0 0 0 0 0 Not stylish Handsome 0 0 0 0 0 0 0 Ugly Elegant 0 0 0 0 0 0 0 Plain
Sexy 0 0 0 0 0 0 0 Not sexy
Trustworthiness
5. The source of the message is in my opinion: Dependable 0 0 0 0 0 0 0 Undependable Honest 0 0 0 0 0 0 0 Dishonest Reliable 0 0 0 0 0 0 0 Unreliable Sincere 0 0 0 0 0 0 0 Insincere Trustworthy 0 0 0 0 0 0 0 Untrustworthy
Expertise
6. The source of the message is in my opinion: Expert 0 0 0 0 0 0 0 Not an expert Experienced 0 0 0 0 0 0 0 Inexperienced Knowledgeable 0 0 0 0 0 0 0 Unknowledgeable Qualified 0 0 0 0 0 0 0 Unqualified Skilled 0 0 0 0 0 0 0 Unskilled Self-efficacy
7. ‘How confident are you that you will be able to exercise regularly in the next three months?’
Very unconfident 0 0 0 0 0 0 0 Very confident
8. ‘How confident are you over the next three months that you could overcome obstacles that prevent you from exercising regularly?’
Completely unconfident 0 0 0 0 0 0 0 Completely confident 9. ‘I believe I have the ability to regularly exercise in the next three months’
Definitely do not 0 0 0 0 0 0 0 Definitely do Attitude
10. ‘For me, to exercise at least 20 minutes, three times per week for the next three months would be’:
very bad 0 0 0 0 0 0 0 very good
not important 0 0 0 0 0 0 0 very important very unpleasant 0 0 0 0 0 0 0 very pleasant very stressful 0 0 0 0 0 0 0 very relaxing very useless 0 0 0 0 0 0 0 very useful very harmful 0 0 0 0 0 0 0 very beneficial very absurd 0 0 0 0 0 0 0 very intelligent. Intentions
11. ‘I have thought about exercising three times a week at least 20 minutes for the next three months’
strongly disagree 0 0 0 0 0 0 0 strongly agree
12. ‘I will try to exercise at least 20 minutes, three times a week for the next three months’:
strongly disagree 0 0 0 0 0 0 0 strongly agree
13. ‘I will try to make an effort to exercise three times per week for at least 20 minuets for the next three months’
strongly disagree 0 0 0 0 0 0 0 strongly agree
14. ‘I will attempt to exercise for at least 20 minutes, three times per week the next three months’
15. You were exposed to an Instagram post. What type of source did you see? 0 I saw an Instagram post from a female athlete persuading me to exercise 0 I saw an Instagram post from a male athlete persuading me to exercise 0 I saw an Instagram post from a female influencer persuading me to exercise 0 I saw an Instagram post from a female athlete persuading me to exercise 16. On a scale from 1 to 10 to what extent do you feel the source was credible? not credible 0 0 0 0 0 0 0 0 0 0 very credible
