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The exercise motivation scale: Its multifaceted structureand construct validityFuzhong Li aa Oregon Research Institute, Eugene, OR

Online Publication Date: 01 March 1999To cite this Article: Li, Fuzhong (1999) 'The exercise motivation scale: Itsmultifaceted structure and construct validity', Journal of Applied Sport Psychology,11:1, 97 - 115To link to this article: DOI: 10.1080/10413209908402953URL: http://dx.doi.org/10.1080/10413209908402953

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JOURNAL OF APPLIED SPORT PSYCHOLOGY 11, 97-1 15 (1999)

The Exercise Motivation Scale: Its Multifaceted Structure and Construct Validity

FUZHONG LI

Oregon Research Institute, Eugene, OR

Building upon Deci and Ryan’s (1985, 1991) self-determination theory as well as previous empirical work on motivation, this paper presents studies on the devel- opment and validation of a multifaceted 31-item Exercise Motivation Scale (EMS). Evidence for the factorial validity of the EMS was sought for eight facets of the exercise motivation construct (amotivation, external regulation, introjected regulation, identified regulation, integrated regulation, intrinsic motivation to learn, intrinsic motivation to accomplish tasks, and intrinsic motivation to expe- rience sensations). Results from various analyses showed adequate evidence for the a priori hypothesized EMS factorial structure, acceptable subscale reliability estimates, and nomological validity. Findings provided initial empirical support for the applicability of self-determination theory in the context of exercise, and indicate the need for a multifaceted approach to the conceptualization of exercise motivation.

Understanding motivation for engaging in physical activity has been a central research topic in sport and exercise science. One theoretical ap- proach to the study of human motivation is Deci and Ryan’s (1985, 1991) self-determination theory. Based on Deci’s (1975) early work, Deci and Ryan (1985, 1991) proposed a multidimensional conceptualization of mo- tivation involving three general facets: (a) amotivation, (b) extrinsic mo- tivation, and (c) intrinsic motivation. These different facets of motivation are further delineated into several distinctive dimensions comprising amo- tivation, external regulation, introjected regulation, identified regulation,

This paper was based on a dissertation completed under the guidance of Vicki Ebbeck and Terry Wood at the Oregon State University, Corvallis, OR. The author would like to thank Elizabeth Hart, Edward McAuley, and Luc Pelletier for their helpful comments during initial EMS items development. The author would also like to extend the appreciation to Vicki Ebbeck, Peter Harmer, and Lisa Strycker for their valuable comments in the manu- script.

All correspondence should be addressed to: Fuzhong Li, Ph.D, Oregon Research Institute, 1715 Franklin Blvd., Eugene, OR 97403, Tel: (541) 484-2123, Fax: (541) 484-1108, E-mail: fuzhongl@ori.org

97 104-3200/99/0097-01 I S 1 .oo/o Copyright 1999 by Association for Advancement of Applied Sport Psychology

All rights of reproduction in any form reserved.

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integrated regulation, and intrinsic motivation, which form a continuum from an external to an internal perceived locus of causality conforming to a simplex-like pattern (Deci & Ryan, 1991; Ryan & Connell, 1989). This pattern suggests that relationships among types of motivation should correspond to the underlying self-determination continuum ranging from amotivation (lowest level of self-determination) to intrinsic motivation (highest level of self-determination).

The proposed multidimensional nature of human motivation has gained much from empirical results that support the existence of separate di- mensions of the motivation construct (Grolnick & Ryan, 1987; Ryan & Connell, 1989; Vallerand et al., 1992). Within this conceptualization, scales have been developed to assess content representing the various types of intrinsic and extrinsic motivation as well as amotivation. In par- ticular, Vallerand and his associates initiated a series of studies to develop and validate a motivation measure modified for each of the academic, sport, and leisure domains (Brikre, Vallerand, Blais, & Pelletier, 1995; Pelletier et al., 1995; Pelletier, Vallerand, Blais, & Brikre, 1990; Vallerand et al., 1992). Their work (Vallerand, Blais, Brikre, & Pelletier, 1989) also extended Deci’s ( 1975) intrinsic motivation conceptualization by propos- ing a tripartite taxonomy of intrinsic motivation: (a) intrinsic motivation to know, (b) intrinsic motivation to accomplish things, and (c) intrinsic motivation to experience stimulation.

The sport version of the motivation measure, initially developed in French (Briere et al., 1995) and further validated in English (Pelletier et al., 1995), has been shown to have construct validity for the various forms of motivation outlined in Deci and Ryan (1985). The measure consists of seven subscales that measure three types of intrinsic motivation (IM: IM to know, IM to accomplish things, and IM to experience stimulation), three forms of regulation for extrinsic motivation (identified, introjected, and external), and amotivation (see Pelletier et al., 1995, for detailed definition of each construct). It should be noted that in both of these studies (Brikre et al., 1995; Pelletier et al., 1995) integrated regulation, representing a fully self-determined form of extrinsic motivation, has not been identified empirically as a unique component of extrinsic motivation in sport settings.

Given the fact that the motive for engaging in activity is a function of both intrinsic and extrinsic motivating factors (Dishman, 1984; Dishman, Sallis, & Orenstein, 1985; Weinberg, 1984), self-determination theory provides a unique framework for studying and understanding multifaceted motivational orientations in the adoption of, and continued participation in, exercise and physical activity. In addition, the theory allows investi- gation of critical antecedents of motivational processes and of the cor- relates and consequences of those processes (Deci & Ryan, 1991). Given these positive features of the theory and its relevance to exercise behavior research, it is important that the theory be employed as a useful research framework in the domain of exercise.

Additionally, an instrument that is specifically designed to measure

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multifaceted exercise motivation would further facilitate substantive re- search in this area. Although the development of the sport motivation measure has proved useful, it has been argued that motivations in sport and exercise settings may differ (Frederick & Ryan, 1995; Vallerand, Deci, & Ryan, 1987). For example, unlike sport participation, common incentives such as weight loss, improved physical attraction, and health concerns are possible catalysts in physical activity (exercise) participation. The development of an exercise motivation measure that uses the same theoretical underpinning as the sport motivation measure, but utilizing a different population should give exercise researchers valuable insights about multifaceted motivations and their influences in exercise.

From a measurement standpoint, existing exercise motivation measures have focused solely on an intrinsic conceptualization (e.g., the exercise version of the Intrinsic Motivation Inventory (IMI) by McAuley, Wraith, & Duncan, 1991; the Self-Motivation Inventory by Dishman, Ickes, & Morgan, 1980). Therefore, a significant limitation in this area is the lack of an instrument that assesses the multidimensional nature of motivation. To understand these diverse motivating factors in the context of an ex- ercise setting, it is imperative that a self-report scale that reflects the various facets of motivation be available.

Thus, building upon Deci and Ryan’s (1985, 1991) self-determination theory as well as previous empirical work on sport motivation (Bribre et al., 1995; Pelletier et al., 1993, the primary purpose of this article is to present the results of three studies dealing with the development and validation of an Exercise Motivation Scale (EMS). The EMS is designed to assess motivational tendencies in the exercise context and, therefore, is intended to be used as a contextual scale in substantive research. The overall objective of these studies was to develop and validate an Exercise Motivation Measure that corresponds to the dimensions proposed by Deci and Ryan (1985) and work by Vallerand and his associates (Bribre et al., 1995; Pelletier et al., 1995; Vallerand et al., 1992). Given the possibility that some physical activities may be less intrinsically motivated (i.e., par- ticipation for reasons such as losing weight or feeling more attractive) and entail time commitment, effort, and persistence, it is likely that an exercise participant experiences the most self-determination for extrinsi- cally motivated behavior accompanied by the feeling of integrity in action and coherent sense of self. For example, an individual chooses to partic- ipate in exercise because it helps him or her stay healthy even though it requires that the individual invest less in other important life activities. Based on this reasoning, it was postulated that the dimension of integrated regulation would emerge as a perceived reason for participation in exer- cise.

In addition, although several investigations have included analyses of gender differences in motivation scores (e.g., Bribre et al., 1995; Fortier, Vallerand, Bribre, & Provencher, 1995; Li & Harmer, 1996; Pelletier et al., 1995; Vallerand & Bissonnette, 1992), the potential gender differences in the equivalency of measurement items have been virtually ignored.

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Therefore, the study has also sought to examine the equivalence issue in addition to examining motivational differences in mean levels across male and female exercisers. An additional analysis was also conducted to ex- amine motivational differences between frequent and non-frequent exer- cisers. Finally, within the self-determination theoretical framework a va- riety of relevant variables thought to be related to the antecedents and consequences of motivation were examined in a nomological model test. Of antecedents, the three most pertinent variables discussed at length by Deci and Ryan (1985, 1991) were: (a) competence, (b) autonomy, and (c) relatedness. Of consequences of motivation, exercise interest and ef- fort, which represent common motivational outcomes in physical activity and education (e.g., Bri2re et al., 1995; Pelletier et al., 1995; Ryan & Connell, 1989), were included.

STUDY 1 Study 1 was designed to construct domain-specific content of EMS in

three phases. Phase 1 focused on the conceptual formulation of motivation proposed by Deci and Ryan (1985, 1991) as well as on the existing in- strument for measuring sport motivation (Pelletier et al., 1995). The three major motivational orientations were expected to represent reasons for physical activity: (a) intrinsic motivation (IM), (b) extrinsic motivation (EM), and (c) amotivation. Underlying these motivators, eight factors were postulated to be related to exercise motivation comprising the three types of IM aforementioned, four types of EM (external, introjected, iden- tified, and integrated regulation), and amotivation.

Phase 2 involved a review of the existing exercise psychology literature to identify the descriptive reasons why individuals exercise, which might then be used to represent each of the eight theoretical constructs. The review included both exercise- and sport-related literature on participation motivation (e.g., Dishman et al., 1985; Ebbeck, Gibbons, & Loken-Dahle, 1995; Masters, Ogles, & Jolton, 1993; Sallis & Hovell, 1990). Reasons were scrutinized by the author for similarity, applicability to exercise, and frequency of appearance.

Phase 3 involved generating reasons from open-ended responses con- cerning why individuals exercise. This approach allowed members of a focus group, in this case the exercise participants, to be involved in the scale development process as active agents who express the meaning of exercise involvement. A total of 101 college students were recruited from physical activity classes in this phase. Students were asked to answer the questions: (a) “Why do you presently participate in exercise activities such as aerobic dance, swimming, jogging, and weight training,” and (b) “Why do your friends participate in exercise activities such as the ones just described?” A total of 57 open-ended responses were collected from the participants. A Delphi method (cf. Thomas & Nelson, 1990) was then employed to analyze the responses. The method involves the use of a panel of experts to evaluate the research questions under investigation

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and may consist of a series of rounds before a final consensus is reached by the panel. Using this method, a panel of raters (N = 3, consisting of both graduate students and physical activity instructors who were knowl- edgeable in exercise and sports science and familiar with exercise activ- ities, was formed to evaluate the content of the responses and provide categorization of these responses. A category was retained if agreement among the panel members was 95% and above.

After five rounds of the Delphi process, a total of four general cate- gories representing reasons for exercise participation were identified: (a) health, (b) self-esteem, (c) social, and (d) positive feelings. These iden- tified general categories were incorporated into each category of moti- vation specified by the theory which resulted in an initial pool of 33 items. The items were then scrutinized by two physical activity instructors for clarity in writing and content ambiguity. Next, the 33 items were evalu- ated by a panel of experts consisting of three exercise and sport psy- chologists who were familiar with the conceptual distinctions of the dif- ferent forms of motivation postulated by self-determination theory. The responses from the three panel members were examined and a decision was made to modify, delete, or add items. As a result of these systematic content evaluations, a 32-item initial version of the EMS was developed.

The final pool of 32 EMS items was incorporated into eight subscales, four items each, assessing the three types of intrinsic motivation (IM; IM to learn, IM to accomplish tasks, and IM to experience sensations), four types of extrinsic motivation, and amotivation. It should be noted that, although the labels of the three IM subscales are somewhat different from those of the sport scale (Pelletier et al., 1995), they were specifically chosen to fit the context of exercise.

STUDY 2 The purpose of this study was to construct an EMS instrument and

provide initial evidence of its psychometric properties.

Method A total of 371 college-aged males and females volunteered to partici-

pate in this study. Participants were selected from: (a) weight training, (b) aerobic dance, (c) jogging, (d) conditioning, and (e) swimming activity classes. Informed consent was obtained from each participant.

A Likert-type response format was adopted for the EMS because it is one of the most frequently employed self-report devices in exercise and sport psychology research and is easy to administer (i.e., readily under- stood and time efficient). Unlike the Sport Motivation Scale, which uses a 7-point Likert-type scale (ranging from Does not correspond at all to Corresponds exactly), all items of the EMS utilized a 6-point Likert-type scale, ranging from 1 (StrongZy Disagree) to 6 (StrongZy Agree). The even number of response options is advantageous since it does not allow for the rating of a middle point as “neutral,” which might suggest uncertainty

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about item meaning. It forces the respondent to either disagree (to a cer- tain extent) or agree (to a certain extent) on the item in question. One potential drawback of using this agree/disagree type scale is that it may lead to a ceiling effect with certain subscales items. For example, it is likely that some individuals may agree with most reasons listed under intrinsic motivation.

The inclusion of four items for each subscales was done to provide reliable indicators for the respective construct and a manageable number of items in analyses (e.g., structural equation modeling). When complet- ing the EMS, participants were asked “Why are you currently partici- pating in this activity?” and indicated their degree of agreement with each of the EMS items using the 6-point Likert scale described previously.

Analysis

Because the EMS structure was specified a priori, a confirmatory factor analysis, using LISREL (Joreskog & Sorbom, 1993), was employed to test the tenability of the proposed EMS internal structure.

Results

Descriptive statistics. Means for the 3 1 items ranged from 1.56 to 5.5 1 . Standard deviations indicated adequate variability for all subscales and ranged from .12 to 1.82. Among the eight subscales of the EMS, identified regulation was most strongly endorsed in this sample ( M = 5.51, SD = .39), followed by IM to experience sensations ( M = 4.89, SD = .33), IM to accomplish tasks ( M = 4.73, SD = .30), integrated regulation (M = 4.61, SD = .17), IM to learn ( M = 4.60, SD = .12), introjected regulation ( M = 3.57, SD = 1.82), external regulation ( M = 2.19, SD = .47), and amotivation ( M = 1.56, SD = .36).

The EMS model jit. The EMS model yielded a statistically significant chi-square test statistic, x? (436, N = 371) = 1052.96, p < .001. Good- ness-of-fit indices also indicated a relatively poor fit of the model to the exercise data; Tucker-Lewis index (TLI; Tucker & Lewis, 1973) = .84, comparative fit index (CFI; Bentler, 1990) = 36, and root mean square error of approximation (RMSEA; Steiger & Lind, 1980) = .08. Exami- nation of the factor loadings indicated that one of the amotivation items loaded negatively and nonsignificantly on the latent amotivation construct. It was, therefore, removed from this subscale. The model was re-estimated and the fit was improved; x? (406, N = 371) = 940.79, p < .001, TLI = .88. CFI = .89, and RMSEA = .06. Inspection of the factor loadings indicated that all loadings were statistically significant and moderate in size ranging from .59 to .88 (standardized) with an average value of .71.

Reliability. Values of internal consistency of the subscales varied from .75 to .90 with an average value of 30, suggesting adequate reliability. Temporal stability (i.e., test-retest with a I-week interval) of the EMS, based on an independent sample (N = 56), was quite high, ranging from .78 to .88 with average value of 32 .

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Summaries Findings from this study provided evidence for the internal structure

of the EMS. Specifically, the eight-factor EMS measurement model was shown to fit an exercising college student sample. The scale was further shown to have adequate internal consistency and stability over a l-week interval. Taken together, results suggested that the EMS possessed valid and reliable psychometric properties and therefore was appropriate for use in the primary study.

STUDY 3 The primary purpose of this study was to further examine the validity

of factor structures underlying the EMS by testing: (a) the eight factor structure of EMS, (b) a higher-order factor structure consisting of intrinsic motivation, extrinsic motivation, and amotivation, (c) a simplex structure reflecting the proposed continuum of self-determination (Deci & Ryan, 1985), and (d) the nomological validity of EMS by linking EMS con- structs to some selected theoretical constructs deemed to be antecedents and consequences of motivation.

Additional purposes of the study included examining the equivalence of EMS items for males and females, and differences in latent construct means across gender and frequent and non-frequent exercisers. Research has indicated gender differences in motivational orientations (e.g., Brikre et al., 1995; Pelletier et al., 1995; Vallerand & Bissonnette, 1992) in that females tend to have higher intrinsic-related motivation orientation than males, and males tend to exhibit higher external regulation than females. The extent to which differences are generalizable to the exercise popu- lation remains unknown. It is also of substantive interest to examine whether frequent exercisers differ from non-frequent exercisers in various types of motivational orientations.

Participants The participants in this study consisted of 598 (205 male and 393

female) college students recruited from two universities in the Pacific Northwest region of the USA. Participants ranged in age from 17 to 30 with a mean of 21.49 years (SD = 2.99) and were primarily Caucasians (84.7%), with the remainder of the sample consisting of Asians (8.45%), African-Americans (4.85%), and Hispanics (2.0%).

At the time of data collection, all participants were involved in a variety of physical activity classes offered through the university during the spring and summer terms of 1995. A total of 35.5% of the subjects par- ticipated in aerobics, 31.1% in weight training, 13.2% in swimming, 11.7% in jogging, and 8.6% in conditioning classes. In addition, self- report on exercise patterns outside class revealed that 38.7% did no ex- ercise activity outside the class, 12.5% exercised once a week, 12.7% exercised twice a week, 23.1% exercised three times a week, and 13.0% exercised more than three times a week.

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Measures

Six self-report measures were assessed: (a) exercise motivation, (b) perceived exercise competence, (c) perceived exercise autonomy, (d) per- ceived social relatedness, (e) exercise interest, and (f) exercise effort. Measures (b) through (f) were used for nomological validity test.

Exercise mofivarion. The EMS developed from Study 1 and validated in Study 2 was used. The scale contains subscales of amotivation reflected by sample items such as “I can’t understand why I am doing this,” ex- ternal regulation reflected by items such as “To satisfy people who want me to exercise,” introjected regulation reflected by items such as “Be- cause I must exercise to feel good about myself,” identified regulation reflected by items such as “Because I think it is a good thing for my personal growth,” integrated regulation reflected by items such as “Be- cause it is consistent with what I value,” IM to learn reflected by items such as “For the pleasure of understanding this activity,” IM to accom- plish tasks reflected by items such as “For the pleasure of mastering this activity,” and IM to experience sensations reflected by items such as “For the satisfaction I feel when I get into the flow of this activity.” A copy of this scale is available upon request.

Perceptions of exercise Competence. The sports competence subscale of the Physical Self-Perception Profile (Fox, 1990) was adapted to mea- sure participants’ perceptions of competence in an exercise setting. The original subscale contains six items measured on a 4-point structured- alternative response format, where a score of 4 is indicative of high per- ceived competence. Modifications were made so that the scale measured perceptions of competence within the context of an exercise activity. For example, a sample item is “Some people are not quite so confident when it comes to taking part in this activity.” An analysis of intercorrelations among the six items indicated that two of the items (i.e., “Some people are sometimes a little slower than most when it comes to learning new skills in this activity” and “Given the chance, some people are always among the first to join in this activity”) had low correlations with the remaining four items and were removed. The reliability for the remaining four items was found to be adequate both in the pilot testing (a = .76, N = 101) and the final study (a = .87, N = 592).

Perceptions of exercise autonomy. A modified version of the Exercise Objectives Locus of Control Scale (EOLOC; McCready & Long, 1985) was used to assess perceptions of autonomy. The EOLOC consists of three 6-item subscales-Internality, Powerful Others, and Chance. Only items from the internality subscale were used in the present study of which a sample item is “I am directly responsible for whether or not I reach my exercise goals in this activity.” Participants responded to each item using a 5-point Likert scale with the anchoring ranging from 1 (Srrongly Disagree) to 5 (Srrongly Agree). The scale was shown to pos- sess satisfactory internal consistency both in the pilot testing (a = 35, N = 101) and the final study (a = .87, N = 592).

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Relatedness. The teacher subscale of the Social Support Scale for Chil- dren (SST-T; Harter, 1985) was used to assess participants’ social relat- edness with significant others. The SST-T is designed to assess children’s perceptions of their teacher’s support and regard. The word “people” was substituted for the word “teacher” to indicate significant others. The SST- T consists of six items. Using a structured-alternative response format, the participants were asked to indicate what kind of people they are most like. For instance, participants responded to an item “Some people do know an individual who helps them do their very best” and then decided if the description was “sort of true” or “really true” of themselves. Item responses were scored on a 4-point scale, where a score of 1 indicated low perceived support and a score of 4 indicated high perceived support. The scale was found to have an acceptable reliability both in the pilot testing (a = .78, N = 101) and the final study (a = 3 6 , N = 592).

Exercise interest. The interest construct was measured by a four-item scale drawn from the interest/enjoyment subscale of the IMI (McAuley et al., 1991). Items reflecting interest toward an activity (e.g., “I am very interested in participating in this activity”) were adapted for use in the present study. The scale showed satisfactory reliability both in pilot test- ing (a = .83, N = 101) and the final study (a = 3 1 , N = 592).

Exercise efSort. The effort construct was assessed using a four-item scale adapted from two sources. One item, “I try hard to do well in this activity,” was derived from Ryan and Connell’s (1989) work in assessing children’s effort in school work. The item has been adapted and used in the sport setting as well (Pelletier et al., 1995). The remaining three items were adapted from the IMI effort-importance subscale (McAuley et al., 1991). Items reflecting effort were adapted to suit exercise activity. The scale demonstrated satisfactory reliability both in pilot testing (a = 3.5 , N = 101) and the final study (a = .88, N = 592).

Procedures

The questionnaires were administered to the participants at either the beginning or end of a class session by the author. All participants signed an informed consent form before filling out the questionnaires.

Data Analyses

Analyses were conducted on responses from participants who com- pleted all questionnaires (amounting to 99% of those who participated in the study). All models proposed in the present study were tested via structural equation modeling using the LISREL program (Joreskog & Sorbom, 1993). Covariance matrices were used as input matrices for all model tests. The overall analyses proceeded in four major stages.

In Stage 1, four first-order factor models of exercise motivation were hypothesized to account for the matrix of intercorrelations of the moti- vation variables: Model 1-a single-facet, general motivition model; Model 2-a three-facet model of intrinsic motivation, extrinsic motiva-

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tion, and amotivation; Model 3-a three-facet model containing self-de- termined forms of motivation (i.e., the three IM subscales, and integrated, and identified regulation subscales), less self-determined forms of moti- vation (i.e., introjected and external regulation subscales), and amotiva- tion; and Model &an eight-facet model representing the fully hypoth- esized model.

In Stage 2, three higher-order models of exercise motivation were pos- tulated to account for the covariances among the eight low-order EMS factors. The first model, H, , corresponds to the three forms of motiva- tional orientation (intrinsic motivation, extrinsic motivation, and amoti- vation) and represents the hypothesized model. The second model, H2, represents an alternative theoretically plausible model and postulates the existence of three forms of higher-order factor structure representing the self-determination continuum from the highest to the lowest level of self- determination: self-determined form of motivation, less self-determined form of motivation, and amotivation. The third model, H,, is an eight first-order factor model that is specified in order to compare models.

In Stage 3, a simplex model was tested using covariance structure anal- ysis. A simplex model examines the relationship of each latent variable to the next in a linear sequence in which the strength of the relationship between each latent variable is indicated by a path coefficient (see Li & Harmer, 1996, for an example of testing the simplex model). In line with the original theoretical propositions of Deci and Ryan (1985, 1991), the construct of intrinsic motivation was operationalized by three intrinsic motivation factors (i.e., IM to learn, IM to accomplish tasks, and IM to experience sensations) using composite scores from each of these factors.

In Stage 4, a model that focuses on the antecedents and consequences of various forms of motivational orientations was tested to establish the nornological validity of the EMS. Specifically, perceptions of competence, perceptions of autonomy, and social relatedness variables were specified to predict various facets of EMS constructs, which, in turn, predicted consequence variables of exercise interest and effort.

Results

Descriptik'e statistics for EMS. Examination of descriptive statistics in- dicated very similar patterns to those found in Study 2. Means for the 31 items varied considerably and ranged from 1.33 to 5.60. Standard devi- ations ranged from .19 to 1.56. Among the eight subscales of the EMS, motivational orientation categorized as identified regulation, was most strongly endorsed in this sample of college students ( M = 5.34, SD = .24), followed by IM to experience sensations ( M = 4.87, SD = .23), IM to accomplish tasks ( M = 4.80, SD = .28) , integrated regulation ( M = 4.74, SD = .19), IM to learn ( M = 4.35, SD = .18), introjected regulation ( M = 3.52, SD = 1.56), external regulation ( M = 2.11, SD = .43), and amotivation ( M = 1.37, SD = .23).

The oiTerull jit of the EMS measurement model. Goodness-of-fit indices

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Table 1 Intercorrelations among the EMS subscales

Subscale ~~

1 2 3 4 5 6 7 8

Amotivation ( 1 ) External regulation (2) Introjected regulation ( 3 ) Identified regulation (4) Integrated regulation ( 5 ) IM to learn (6) IM to accomplish tasks (7) IM to experience sensations (8)

Note. IM = intrinsic motivation.

1 .oo .51 1.00 .12 .49 1.00

-.38 -.15 .40 1.00 -.32 -.04 .46 .85 1.00 -.24 -.05 .02 .33 .49 1.00 -.32 -.07 .24 .69 .88 .67 1.00 -.36 -.24 .10 .57 .65 .67 3 3 1.00

indicated that the a priori, eight-factor model (M,) fit the data substan- tively better than the alternative one-factor model (x2 (434, N = 592) = 4,058.17, TLI = .46, CFI = S O , RMSEA = .12) or the two three-factor models (x’ (431, N = 592) = 3,405.18, TLI = .56, CFI = .59, RMSEA = . 1 1 for M,, x 2 (431, N = 592) = 2,434.39, TLI = .70, CFI = .72, RMSEA = .09, for M,, respectively). Chi-square difference, nested-model comparisons also revealed a better fit of the M, model than remaining models: x ~ ~ , ~ ~ = 3,017.90, dfdlff = 28, p < .001, between M, and M,; x2dw = 2,364.91, dfdlff = 25, p < .001, between M, and M,; xZdltf = 1394.12, dfdtff = 25, p < .001, between M, and M,. Note that the chi-square dif- ference test between M, and M, was not conducted because the two mod- els were not nested.

Inspection of the factor loadings for the eight-factor model indicated that all eight factors were well defined. Every factor loading was statis- tically significant (at the .001 level) and reasonably substantial in size (the standardized loadings ranged from S O to .84 with an average value of .67).

Finally, the relationships among all the EMS subscales, shown in Table 1, were reasonable. The lower level of self-determination factors (e.g., amotivation, external regulation, and introjected regulation) were all cor- related among themselves (ranging from -.38 to .88 with an average value of .37) with the first two negatively correlated with the remaining factors. Factors from intermediate to high levels on the self-determination continuum (e.g., identified regulation, integrated regulation, and the three IM factors) were found to be positively and moderately related (M = .66).

Equivalence of EMS items across gender. A model was also estimated with gender as a single-item factor that was allowed to be correlated with each of the eight latent first-order factors. The specification allows a straight-forward description of gender differences in the constructs con- sidered. Modification indices (MI) from LISREL for the EMS items on

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Table 2 Parameter estimates (path coefficients) for the simplex model

Estimate Unique Parameter (Standardized) t-value.' variance

Amotivation + External Reg. .49 1.97 .76

Introjected Reg. -+ Identified Reg. .38 6.24 .86 External Reg. -+ Introjected Reg. .44 6.59 .8 1

Identitied Reg. + Integrated Reg. -85 10.89 .2x Integrated Reg. + Intrinsic Motivation .x0 10.88 .36

Nore. Values of 1.96 are significant at p < .0S.

the "gender" factor were all small and nonsignificant, providing support for the hypothesis that the items work similarly for males and females.

Reliabiliv of EMS subscales. The reliability of the items used to mea- sure the eight exercise motivation subdimensions was evaluated by cal- culating the internal consistency reliability (Cronbach, 195 l ) for each subscale. The alphas averaged .77, ranging from a low of .71 (IM to accomplish tasks) to a high of .85 (IM to learn), and meet established standards at this early stage of development (Nunnally, 1978).

The overall j t for the higher-order factor models. In general, the two higher-order factor models, H, and H,, yielded significantly poorer fit (TLI = 34, CFI = .85, RMSEA = .06, for H, , TLI = .85, CFI = .86, RMSEA = .07, for H1) to the exercise data compared to the M, model (TLI = .90, CFI = .91, RMSEA = .05), which was used as a baseline model. These model fitting statistics suggested that the proposed higher-order factor configurations failed to account for the covariations among the eight lower-order factors.

Examination of parameter estimates from H, and H2 models also showed signs of an identification problem. Specifically, negative residual variances were found in the models. For example, two nonsignificant negative residual variances were revealed in the HI model (variance of integrated regulation and IM to accomplish tasks) and in the M2 model (variance of external regulation). Thus, because of inadequate fit and un- acceptable out-of-bounds parameter estimates, the higher-order models proposed in this study were rejected.

The overall j t for the simplex model. The LISREL analysis for the simplex model resulted in the following model fit: x2 (204, N = 592) = 726.94, p < ,001, TLI = .89, CFI = .89, and RMSEA = .07, suggesting that the proposed simplex structure in the data was tenable. Table 2 pre- sents standardized estimates (i.e., path coefficients) and residual variances for the simplex model. These coefficients indicate the strength of the relationship between each pair of motivational constructs along the self- determination continuum. Examination of these path coefficients revealed that all coefficients from the construct of amotivation to intrinsic moti- vation were statistically significant ( p < .05). Results were consistent with

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the hypothesis, suggesting that each construct was substantively related to the next in a linear sequence conforming to a simplex pattern. Variance explained by each preceding variable ranged from 14% to 72%.

To test whether the regression coefficients of the simplex model were invariant across gender, a model including a factor of gender was tested. Differences in path coefficients were examined using MI provided by LISREL. Inspection of the MI indicated no large index that would point to the differences in the regression coefficients, suggesting the simplex structure was invariant across the male and female samples.

Tests for latent mean diflerences across gender and frequent vs. non- frequent exercisers. Tests of latent mean differences were conducted (see Li, Harmer, & Acock, 1996, for an example of latent mean analysis). Using the male sample as a reference group, results from gender analysis indicated that females reported higher levels of intrinsic motivation (IM to learn, M = .23, p < .05, IM to accomplish tasks, M = .41, p < .01, and IM to experience sensations, M = .35, p < .01) and self-determined forms of motivation (integrated regulation, M = .23, p < .05, identified regulation, M = .12, p < .05) than their male counterparts. In addition, female participants also reported lower levels of external regulation (M = -.17, p < .05) and amotivation (M = -.20, p < .05) than male par- ticipants.

In analyzing differences across frequent vs. non-frequent exercisers, participants were divided into frequent (n = 290) and non-frequent (n = 302) exercisers based on their report of exercise frequency. Non-frequent exercisers were those who reported no exercise or exercise once a week while frequent exercisers were those who reported exercised twice or more a week. Using the non-frequent exercisers sample as a reference group, results indicated frequent exercisers showed higher levels of IM to learn (M = .32), IM to experience sensations ( M = .41, p < .Ol), integrated regulation (M = .14, p < .05), and identified regulation (M = .23, p < .05) than non-frequent exercisers.

Nomological validity analysis. The hypothesized structural model tested provided a reasonable fit to the data, as suggested by the goodness of fit indices: x2 (1,352, N = 592) = 3,699.03, p < .001, TLI = .82, CFI = 3 3 , RMSEA = .05. Estimates in the model indicated that most hypoth- esized relationships were tenable. For the relationships between percep- tions of competence and various facets of exercise motivation, results indicated that perceptions of competence were (a) significantly and pos- itively related to the three forms of intrinsic motivation (IM to learn, y = .13; where y indicates a path coefficient, IM to accomplish tasks, y = .20; and IM to experience sensations, y = .22) and the three forms of extrinsic motivation (integrated regulation, y = .20; identified regulation, y = .22; and external regulation, y = .12) and (b) significantly and neg- atively related to amotivation y = -.13. For the relationships between perceptions of autonomy and various facets of exercise motivation, results indicated that perceptions of autonomy were (a) significantly and posi- tively related to each of the three intrinsic motivation factors (IM to learn,

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y = .16; IM to accomplish tasks, y = .32; and IM to experience sensa- tions, y = .28) and the two self-determined forms of extrinsic motivation (integrated regulation, y = .32; and identified regulation, y = .31) and (b) negatively related to external regulation (y = -.20) and amotivation (y = -.23). For the relationships between perceptions of relatedness and various facets of exercise motivation, results showed that relatedness was (a) significantly and positively related to the three intrinsic motivation factors (IM to learn, y = .16; IM to accomplish tasks, y = .15; and IM to experience sensations, y = .18) and the two self-determined forms of extrinsic motivation (integrated regulation, y = .15; and identified regu- lation, y = .17), and negatively related to external regulation (y = -.14) and amotivation (y = -. 17).

For the relationships between various factors of exercise motivation and consequence variables, the results showed that exercise effort was (a) significantly and positively related to self-determined forms of motivation (i.e., IM to learn, p = .16, where indicates a path coefficient, IM to accomplish tasks, fi = .18, IM to experience sensations, p = .21, inte- grated regulation, p = .11, and identified regulation, f3 = . l 1) and (b) significantly and negatively related to introjected regulation (p = -. 1 1) and amotivation, p = -.lo. Results showed less support for the relation- ships between exercise interest and the eight dimensions of exercise mo- tivation, but a significant and positive relationship was found between intrinsic motivation and exercise interest (IM to learn, p = .18, IM to accomplish tasks, p = .24, IM to experience sensations, p = .31). Ex- ercise interest was found to be significantly and negatively related to introjected regulation, p = -. 12.

Summary and Discussion This article presented results related to the development and validation

of an Exercise Motivation Scale that was grounded on self-determination theory and existing motivation measures from the exercise and sport do- mains. Results from a series of lower-order measurement models indicated that the hypothesized EMS provided the best fit of the exercise data, suggesting that the eight-factor multidimensional EMS provided adequate theoretical representation of the exercise motivation data. The scale showed acceptable reliability. Furthermore, the scale items were shown to be equivalent across males and females for the sample.

Gender results indicated that females reported higher levels of intrinsic motivation and self-determined forms of motivation than their male coun- terparts. Females were also less externally regulated and amotivated than males. These results were consistent with empirical findings in sport and education (e.g., Fortier et al., 1995; Pelletier et al., 1995; Vallerand & Bissonnette, 1992) and suggest similar motivational profiles across several domains. An interesting question for future studies, however, is whether gender contributes to the motivational differences between sport and ex- ercise. Furthermore, results on exercise frequency indicated frequent ex-

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ercisers showed higher levels of Ih4 to learn, IM to experience sensations, integrated regulation, and identified regulation. These findings indicated that frequent exercisers perceive their exercise motivation as more intrin- sic and see themselves as being more self-determined in their exercise engagement than their non-frequent counterparts.

Results on higher-order structure models indicated a poor overall fit. The results are not surprising when the basic tenets of self-determination theory are revisited. According to the theory, when a behavior is initiated by individuals for their own sake, the behavior is considered to be intrin- sically motivated, whereas when a behavior is performed not out of in- terest but believed to be instrumental to some consequence, the behavior is viewed to be extrinsically motivated. With the latter, the theory suggests that there are different types of extrinsically motivated behaviors (exter- nal, introjected, identified, and integrated regulation) as represented in the EMS, and that these differ in the extent to which they represent controlled (i.e., external, introjected regulation) vs. self-determined (i.e., identified, integrated regulation) responding (Ryan & Connell, 1989). These types of motivational orientations, according to self-determination theory, are transformable through a regulation process called internalization, which describes the transformation of controlling types of motivation governed by external contingencies into self-determined types of motivation regu- lated by internal processes. Empirical verification for this was provided by the simplex model analysis.

Using the analysis of covariance, the study showed that the simplex hypothesis underlying the eight dimensions of EMS was tenable for the exercise data, suggesting a linear sequential order for the motivational constructs as proposed by self-determination theory: amotivation + ex- ternal regulation + introjected regulation + identified regulation -+ in- tegrated regulation + intrinsic motivation. The sequence of the relation- ships was found to be similar across gender. The finding provided addi- tional evidence for the EMS factorial validity and reinforced the theoret- ical proposition that perceptions of self-determination are based on a continuum concept of extrinsic and intrinsic motivation (Ryan & Connell, 1989). Results from this exercise data set were also consistent with find- ings from a sport study (Li & Harmer, 1996) using the sport motivation measure (Pelletier et al., 1995). However, the continuum as measured by the EMS differs from the sport-based studies in that it fully incorporates all the dimensions specified by the theory.

Tests on the selected antecedents and consequences of exercise moti- vation showed some evidence of nomological validity, and findings are comparable with the motivation literature in general. The majority of the hypotheses were supported and in the expected direction. Although lack- ing robust estimates (i.e., small magnitude of the coefficients), similar patterns were found between this study and existing empirical studies (Bribre et al., 1995; Pelletier et al., 1995; Ryan & Connell, 1989). For example, Bribre et al. (1995) and Pelletier et al. (1995) showed that in- trinsic-oriented motivation and self-determined forms of extrinsic moti-

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vation were, in general, significantly and meaningfully related to percep- tions of competence, perceptions of autonomy, and social support. Sim- ilarly, they demonstrated that high levels of self-determination are related to higher levels of activity interest and effort (Brikre et al., 1995; Pelletier et al., 1995).

The development and validation of the EMS makes an important con- tribution to exercise research as it offers a theoretically sound and meth- odologically valid and reliable measure. One of the major outcomes of these validation studies is the tenability of the integrated regulation di- mension as proposed by self-determination theory. Previous self-deter- mination theory-based motivation measures have failed to identify this construct as a high level of self-determined motivation (i.e,, Brikre et al., 1995; Pelletier et al., 1995; Vallerand et al., 1992). The recognition of integrated regulation differed from those sport and education motivation measures in that the EMS is not only a content-specific measure of mo- tivation (i.e., exercise motivation) but, more importantly, reflects a full developmental conceptualization of autonomy (Deci & Ryan, 199 1). It implies that for this exercise sample there is a developmental tendency toward greater internalization (i.e., “Exercising is an important aspect of how I view myself”) and that integrated regulation represents the most self-determined form of extrinsic motivation in the exercise domain.

The development of the EMS facilitates empirical research addressing issues of both substantive and methodological interest. For example, in testing hypotheses emanating from cognitive evaluation theory (Deci & Ryan, 1985), Li et al. (1998; see also Li & Harmer, 1998) investigated the interaction of perceptions of competence and autonomy on various types of intrinsic motivation as assessed by the EMS. Support was ob- tained for the proposed interactive effect using structural equation anal- ysis. Also, using the EMS, Li, Duncan, Duncan, Harmer, and Acock (1 997) analyzed between- and within-group variations in intrinsic moti- vation and demonstrated that it is possible to statistically capture the var- iations of motivation through the application of multilevel structural equa- tion modeling methodology.

From a practical point of view, the EMS can be used to measure ex- ercise motivation in various exercise-related programs. For example, it could be used to establish a baseline level of individuals’ exercise moti- vation in certain exercise programs or to examine possible change in the EMS when studying exercise adherence. The EMS can also be applied in intervention programs. As programs are implemented, practitioners could quantitatively measure levels of motivation at different points in time in order to better understand the specific circumstances leading to an increase or decrease in motivation.

Future research should continue EMS validation studies including: (a) continuing the effort to validate the EMS via applied and basic research involving issues related to exercise motivation, (b) using the EMS re- sponses as outcome variables in intervention research, and (c) adminis-

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tering the EMS to other populations (e.g., community- and/or recreation- based exercise programs) to test the generalizability of the current results.

In conclusion, these findings provided initial empirical support for the applicability of self-determination theory in the context of exercise and suggested a multifaceted approach to the conceptualization of exercise motivation. The EMS, overcoming the drawbacks of existing measures, reflects individuals’ perceptions of self-determination ranging from amo- tivation to extrinsic motivation, in which various middle-ground moti- vational orientations are considered, and, finally, intinsic motivation. As a valid and reliable multifaceted exercise motivation measure, the EMS allows one to understand various dimensions of exercise motivation as well as to study the structural relations among antecedents, motivational orientations, and consequences in the exercise domain.

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Final revision submitted: April 28, 1998