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Master of Science Thesis, Western Washington University, Bellingham, Washington, May 1986.Physical fitness testing, exercise reports, and psychological measures were used to assess the role of self-motivation as measured by the Self-motivation Inventory (SMI) (Dishman, Morgan, & Ickes, 1980) in exercise adherence.
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THE ROLE OF SELF MOTIVATION
EXERCISE ADHERENCE
West
A Thesis
Presented
The Faculty
n Washington
to
ofUniversity
Partial Fulfillmentof the uirements for the Degree
Master of Science
by
John W. Clark
May 1986
THE RI)LE OF SELF MOTMTIONIN EXERCISE ADHERENCE
John Clark
Accepterl in Partial CompletionOf the Rerluirements for the Degree
l aster of Science
Arlvisory Conttn1gl..
-W;,On4MRobert M. Thorndike
By
I.I .
Graduate
. Kleinknecht, Chairman
ABSTMCT
Physical fi.tness testirlg, exercise reports, and psychological measureswere used to assess thr: role of self-motivation as measured by theSelf-Motivation Inventr>ry (SMI) (Dishman, Ickes, & Morgan, 1980) inexercise adherence. Pirrticipants were healthy men and women who workedat an industrial plant where the employer was sponsoring a health andexercise program; 334 persons began the study and analyses werecarried out on this grorrp and smaller subgroupings of it dependi-ng onidentifying informatiorr avaj-labIe and on participation in the variousphases of the study. Data were collected on four occasions during theexercise program which continued approximately one year. Some of thesubgroupings for analyr;is had a very sma11 number of subjects with afull set of data due to the voluntary participation and identificationat each of the four da1:a collection sessions. Because of the sma1lnumber of subjects in riome of the subgroupings, the results of thisstudy and inferences dr:awn from the results must be treated wi-thcaution. Stepwise mult:ip1e regression analyses revealed that the SMIcoupled with percent body fat and weight did not account for a significantportion of the variance in exercise adherence as had been reported byDishman and GeLtman (1!f80), though evidence supporting some psycho-biologic mix of factors; was found. The presence of irnmediate rewardsfrom exercise seemed to play a more important role in exercise adherencethan did self-moEivation. Compilation of reasons cited for starting, notstarting, conti-nuing, ernd dropping out of exercise and cluster analysisof reasons cited for sl:arting and not. starting exercise indicated thatthose persons who starl:ed and continued exercise were 1i.ke1y to cite
immediate physical and psychological rewards from exercise while those
who did not start or who dropped out were likely to report difficulty
with scheduling 4nd le:ation of classes and not being motivated enough
to exercise. t-tests at the .05 alpha level revealed that SMI scores
of starters were signiEicantly higher than those of nonstarters, but
that there was no significant difference between SMI scores of those
who dropped out and those who adhered to an exercise program. SMI was
supported as a measure of self-motivation, but it does not appear to be
a pure measure of the ger.etaLj-zed, nonspecific tendency to persevere
defined by Dishman and Gettman (1980). A significant negative correlationbetween a measure of anxiety, the State-Trait Anxiety Inventory (STAI-T)
(spielberger, Gorsuch, & Luschene, L97O) and SMI (r=-.37, n=334) linkinghigher levels of anxiety to lower SMI scores suggests that as different
specific situations elicit different levels of anxiety in participants
the SMI administered in the context of the specific situations will tend
to vary. Self-motivation as measured by the SMI seems to be one factor
in exercise adherence, but the results of this study suggest that the
SMI score is at least partially siEuation specific and that the degree
of irnurediate reward th.e individual perceives as resulting from exercise
is probably more impoltant in exercise adherence than self-motivati-on'
Introduction
Regular, vigorousr physical exercise can have positive effects inseveral areas of life. The body functions better with improvedmetaboli-sm, a lower percentage of fat, and a more efficient use of oxygen.A general feeling of u'el1-being with increased effectiveness in work,sleep, and social behavior is associ.ated with exercise (Folkins & Si_me,1981; Morris & Ilusman, 1978). people who exercise regularly show adecreased tendency tovard heart disease, hypertension, and obesity(Morris, Everitt, Pollard, chave, & semmence, 19g1; paffenbarger, wing, &Hyde, L978). Fina11y, those who exercise display less anxiety, lesstension, less depressi.on, less fati.gue, and more vigor
-than those who donoL (Folkins & Sime, 19811 Blumenthal, wi11iams, Need.els, & wallace, L9B2;Kaplan, Mendelson, & Dubroff, 1983; Fetsch & Spri_nkle, 1983).
The issue of pote:rtia1 benefits of any activity is moot for those whodo not ParticiPate or Eor whom the participation level is not particularlyhigh. In reviewing strrdies of regular exercise Dishman (1982) and Martin& Dubbert (i982) noted that among those who began an exercj_se program,dropout rates between ll0 and 70 percent were conslstent.ly reported. Themost dropouts occurred during the first three months and after L2 to 24months the number of p
between them hold the keys to predicting who will have trouble maintainlngan exercise program. Such prediction might then enable us to tailor anexercise Program to ir.dividual needs and increase the adherence rate.
A number of factcrs related to exercise ad.herence have beenidentified and are divided into three groups: parti-cipant factors(physiological and psychological), social factors (famj-ly, friends,employers, etc.), and exercise program factors (location, schedule,leadership, and content). No one factor or one of the three groups offactors explains exercise adherence by itself; adherence results from ani-nteraction of factors.
Self-notivation (a psychological factor) and how the other factors inexercise adherence rel,rte to it are the central interests of this study.The self Motivation rn'rentory, (sMr), (Dishman, rckes, & Morgan, 19g0) isa paper and pencil tesE designed to measure a personrs level ofself-motivation. Presr:ntly, the sMr is the best single psychologicalpredictor of exereise irdherence (Dishman, rckes, & Morgan, 1990).Therefore, the Purpose of this study is to learn more about what the SMIis measuring, how that measure relates to the construct ofself-motivation, and h
Patterns of dropout. Since the lj.terature on medical compliance has alonger history and more breadth than that on exerci-se adherence it isuseful in the study oE exercise adherence.
In medici-ne, treirtment compliance means following the clinicalprescriptj-on in such r:hj-ngs as taking medications, following hygienicroutines, and making .Lifestyle changes (sackett, Lg76). synonyms areadherencer prsverence, and persistence. Antonyms are dropout, relapse,and recidivism.
The word compliarrce carries negative connotations for some byimplying blind obedierrce to professional dicta. This lmplication isunfortunate because ir. current usage it is felt that the best c1j-nica1prescription i-s formulated by the patient and physician together (Sackett,L976). However, both the history of use of the term compliance andpossible confusion of alternaEive words seem to d.ictate conti-nued. use ofthe term compliance.
Patients tend not to eomply with health related regimens and. thj-snoncompli-ance greatly conplicates treatment planning. rt is notsufficient to determi-ne what patients need to do; the helping professionalmust also get them to do it. until more is known about achieviagtreatment compliance we will continue to have useful treatments thatsignificant numbers of people cannot or will not fol1ow.
Treatment compliarrce behavior does not consistently follow any onepattern, but there are conmonalities that offer starting points forresearch and discussioll. Pati.ents have shown difficulty in mai-ntaining
compliance and simila:: patterns of dropout in such programs as following aphysiciants prescript:Lon for medication and hygiene; abstaining fromalcohol, tobacco, and other addictive substances; continuing inpsychotherapy; dietinl; to lose weight; and exercising regularly (Dishman& Gettman, 1980; Sutton, 1979; Hunt, Barnett, & Branch, L97L; Baekeland &Lundwall, L975).
In addition to tlte rather gross simi-laritj"es in dropout rates andpatterns, Haynes (197(t) has identified some major correlates ofnoncompliance that ap1rly to the variety of health settings that sharedropout Patterns mentj.oned above. These correlates of noncouplianceinclude: (a) psychi.at:ric illness, (b) a regimen that is complex, thatrequires a great deal of behavioral change, that is of long duration, orall of these, (c) treat,ment occurring in clinics that are inefficient,inconvenient, or both, (d) inadequate supervision of the treatment programby the therapist, dissatisfaction with the therapist by the patient, orboth, and (e) a patier,t with inappropriate health beliefs, previous orpresent noncompliance with other regimens, family instability, or all ofthese.
Patient Factors
The main interest in this paper is with psychological factors and howthey relate to other factors in compliance. These psychologi-cal factorsare included in the patient factors that Haynes calls health beliefs.Health beliefs and their relation to other compliance factors have beendescribed by several rnodels including the Health Belief Mode1, Social
Learning Theory, the tftility Model of Preventive Behavior, and the RelapseMode1.
Health Belief Model: The healrh belief model, (HBM), (Rosensrock,L974), was created in a preventive health setting to explain the liklihoodthat a person would comply with a reco 'nended course of action. rtscomponents are:
1. the perceived seriousness of the consequencesof not taking preventive or curative action,
2. the perceived susceptibility of the person tothe negaEive outcome,
3. the perceived barriers and benefits to takingthe pres,:ribed action,
4. the perc,rived efficacy of the prescribedaction.
A general relation bettoeen beliefs and preventive health actions has beenshown to exist in clin:Lcal situations (Aho, 1977). And, as simple as theHealth Belief Model is, it provides a useful framework for study andtherapy.
Clinical applicat:Lon of rhe health betief model has led to abroadening of the orig:Lnal proposal. Jenkins (1979) assembled a set ofspecific questions based on the health belief model that clarified thepatientst beliefs, per(:eptions, motives, needs, learned habits, and socialand physical environment,s for health behavior in order to prescribe a
course of treatment tltat l^rould be cornplied with. Jenkinst compilation ofspecific components irr each personfs compliance structure underscores theassuuption that there can be uo ttstandard regimen,, because there is no"standard patientfr (Fink, 1976).
Even when broadened to include as much personal context as possible,attitudes and beliefs measured before treatment begins have not beenparticularly predictive of long term compliance. Health beli.efs do becomebetter predictors of compliance when measured as treatment progresses(Luborsky, et al., 1980). Furthermore, those who do comply with treatmentdevelop more positive health beliefs as they continue in treatment (Bruhn,i983). Understanding ,cf compliance behavior must include this shaping ofattitudes and beliefs 5y experience.
social learning theory: social learning theory incorporates theinterplay between indi'ridual experience and behavior by viewing humans aslearning, choosingr prr)blem-solving organisms. central concepts areperceptions of threat, rewardr possible solutions, and ability to carryout various actions.
Specific social learning theory concepts such as locus of control,behavioral capability, expectations, self control, and self efficacy havebeen used effectively l:o explain and to iuprove treatment compli.ance(Bruhn, i983). For exemple, it has been found that locus of control (thedegree to which indivicluals believe they control their envi-ronment)explains successes and failures in rigid versus flexible weight-lossprograms (Kincey, 1983). Compliance with a self-care regi-men in
adorescent diabetics uras improved by using self-monitori.ngr goalsetting, and behaviore.l contracting (schafer, Glasgow, & Mccaul, l9g2).
Ilowever, Kaplan 6 cowles (1978) have warned that some commonmisapplications of social learning theory concepts can confoundconclusions about compliance, citing two examples. The first example wasin trying to apply a generalized measure of locus of control to a specificsituation. Individuals who generally have an internal locus of control(feeling thaE they control their environment) may display a very externallocus of control (feeling that their behavior is controlled by forcesoutside themselves) in a specLaLized sett.ing such as medical treatment.The same warning probably has some validity for other generalpsyehological measures being applied in specifj.c situations. The secondmisapplication of social learning theory described by Kaplan & cowlesinvolved trying to explain behavior through beliefs without consi-deri.ngthe values that the inCividual placed on the possible outcomes.
Utility nodel of preventive behavior: The utility model ofpreventive behavior (C,rhen, i984) focuses directly on the valueparticipants put on varlous possible out.comes. Thj-s model is baseddirectly on a model us,rd in Economics to describe how individuals behavewith respect to risk. In the economic model the term "uti1ity" is definedas a very broad measurr: of value which includes all forms of reward intaking a given action be they monetary, personal, or soci-al.
The Utility model retains the rnajor elements of the health beliefmodel such as perceptir>ns of personal risk and costs and benefits ofpreventive acEion, but goes further to assert that the primary motivating
factor in taking prev,rntive action is the anxiety associated withthreat of harm rather than the harm itself. An action that makesindividual feel better i.mmediately is most likely to be followed.
rn the case of a long-term or a preventive regimen the vitar factoris the personal style of the patient i-n d.ealing with risk. Each personhas a 1evel of aversic)n to risk and of willingness to pay now to avoidfuture risk- A persorLfs risk-taking style determines whether a givenbehavior has a positive, negative, or neutral utility at a specific tine.The broad scope of the teru utility is a reminder that even in healthrelated behaviors, health is only one of the possible values that goesinto determining utility level.
. Relapse model: A single lapse can lead a person to drop out of a'Program. The lapse may be overeating while on a weight loss diet, missi-nga therapy session, or Eailing to take medication. Marlatt and Gordon(1980) have suggested E.hat a personts ability to recover from such a lapseand to continue with tl:e prescribed regimen is influenced by the personrscognitive skills in coPing with the relapse. rf the person sees therelapse as proof that he cannot succeed and that he is weak, thenconti-nuing the prescribed regimen is un1ike1y. Marlatr and Gordon (19g0)have suggested that tr:rining in how to deal with relapse can havesignificant effects on the overall adherence rate. Indeed, this model hasbeen applled successful.ly both in stopping an unrrTanted behavior (smoking)(Condiotte & Lichtensterin, 198l), and in encouraging a positive behavior(running) (fing & Frede,riksen, 1984).
the
Ehe
Treatment Factors
The nature of ther treatment itself plays a significant role in thedegree of compliance. If the treatment is painful or has other unpleasantside effects, the char,ce of noncompliance i-s increased. The behavj.or ofclinic staff members, the scheduling of appointments, and the location ofthe treatment site all also play roles in eompliance.
The quality of the relationship between the physician and the patienthas been consistently given a central role in compliance (Ilaynes, et a1.,lg76). Sometimes other factors thaE favor noncompliance cannot be hetpedand the relationship between the patient and physician must be the onethat makes compliance possible. As stated previously, the prescriptionmost 1ikely to be complied with is one jointly determined by patient andphysician. The physicianrs knowledge of disease and treatment must bejoined with hoI^I the patient is being affected or threatened by an ailmentand how that patient deals cogni.tively with health. If the formulation ofthe treatment plan considers the beliefs, habits, capabilities, andexpectations of the patient as well as the content and rationale for thetreatment, chances of achieving compliance are enhanced.
Social/environmental f actors
If the pati-ent I s Eamily supports maintaining the treatment programthe chance of success is great.ly increased. A number of studies showingthe importance of the Eauily i.n adherence to medi-cal treatment have beenreviewed by Haynes (1976). Support of some significant other
10
person is recognized as a vital component of compliance (Bruhn, 19g3)the negative side, fainily instability has already been mentioned as afactor in noncomplian,:e (Haynes , tg76).
No matter what trre rerationship with the physician or the personrsbeliefs, he lives mosl: of the time with his family, friends, and ferlowworkers. The role of other people significant to the patient incompliance suggests ttLat considering only the patient in formulating theprescription may be ol'erlooking some seri-ous problems and opportunities.
Exercise Adherence
The degree of adherence to programs of regular physical exerci.se,like medical adherence, is 1ow. Typicarly, after six months of a programabout 507" of the partir:ipants have dropped out (Dlshman, r9g2). Factorsinvolved j-n exercise arlherence can be grouped into participant factors,soeial/environmental f.rcEors, and program factors. The focus of thisstudy i-s on the psycho:-ogicar components of the participant factorsand how these psycholoS;ical factors relate to other factors in exerciseadherence.
Participant Factors
Attitudes: Perhaps the most obvious psychological measure of whethera Person would exercise or not would be attitude toward exercise. Howeverthis has not been found to be the case. Even very sedentary people have
On
11
been shown to have posri-tive attitudes toward. exercise (Dishman & Gettman,1980) .
Sedentary people who value exercise have attitud.es that are inconflict with their actions. Festinger (L957) described such a conflictas cognitive dissonance. He suggested that when people find themselves ina state of dissonance they are uncomfortable and will try to changesomething to achieve consistency. If consistency is not gained throughacti.on, then the person is likely to redefine his situation so thatbeliefs and actions are consistent. Efforts to achieve this consistencyoften involve distorticns of reality that Freud described as defensemechanisms. In the case of exercise, the person can achieve consistencyeither by exercising o.r by having a reason that is acceptable to him notto exercise. Acceptab Le reasons can include anything that makes theperson feel consistent (be the reasons rational or not), such as having aphysical ailuent that Precludes exercise, not needing to be in betterphysical condition, thr: exercise site being inconvenient, or not havingEime to exercise.
How a sedentary l)erson is resolving the dissonance would seem to bevital in understanding his compliance/adherence patterns. While cognitivedissonance theory and ::esearch seem potentially fruitful in compliance andadherence, studies spe
L2
MotivaEion has beren defined by Lefton (1982) as "... any internalcondition within an or:ganism that appears (by inference) to producegoal-directed behaviot'" (p. 137). It may be caused by some imbalance thatpushes the organism tcr act (drive theory) or by some expectance of adesirable outcome that pu1ls the organism to act (expectancy theory). Itseems likely that the people in Oldridge's study meant that they did notvrant to do the activity badly enough to overcome obstacles to contlnuing.tr{hat it was inside the participants that either made the activity itselfnot positive enough to draw them past the barriers or so unpleasant thattheir desire for good health was not strong enough to push them past thebarriers is, of course, not known, but it can be inferred throughobservable behavior, self-statement, and physical capabilities.
Significant and consistent differences in how people perceive andinterpret the same experience do exist. It has been shown thatdifferences in response to stressful situations can be accounted for bycogni"tive methods people use to deal with them (Koriat, et al., 1972) .The i-nterpretat.ions anil strategies that the partici_pants employ areavailable for study through self-report and changeable through relearning(Meichenbaum, I975). Ihis makes eognitive activity a potentially powerfultool for understanding, predicting, and changing behavior.
A paper and penciL test designed to measure onets tendency topersevere is called t.h,l Self-Motivation Inventory (SMI) (Dishman, Ickes, &Morgan, 1980). The SMt consists of statements that the subject rates I to5 on a scale of trextrernely uncharacteristic of mett to ttextremely
characteristic of me", profiling her or his cognitive interpretations andstrategies relative to perseverence. The SMI has been demonstrated to be
13
the best single psychological predictor of exercise adherence. Dishmanand Gettman (1980) halre called the tendency to persevere that is measured.by the SMI self-motiv:rtion and have defined it as follows:
'... a generalized, nonspecific tendency topersist in t:he absence of exErinsic reinforcementand is thus largely independent of situationalinfluence... ismost likely a socially learnedcharacterist:ic dependent upon the capacity forself-reinforcement it may incorporate theability to c.e1ay gratification ... is apparentlyindependent of concepts such as approvalmotivation, achievemenE motivation, locus ofcontrol, or attributions for success or failure... may invc,lve cognitive ski11s similar toi-magery or fantasy about goal attainment,self-talk strategies, or possibly eongruencebetween self-perception and behaviorrr (p. 297).
Intrinsically motivated behaviors have been described by Edward Decl-(L975) as ones that the person undertakes to feel competent and incontrol. Deci related internal and external motivators by suggesting thatsome goals are self-generated, but externally measured. For example,adherence and effort put i-nto a physical task have been shor^m to increasewhen people achieve their own exercise goals (Martin & Dubbert, L982;Bandura & Cervone, 1983).
Some reference points for deciding whether to persevere or not may bei"nherent in the environment. For example, in a competitive sports settingparticipants have reported an increase in intrinsic and a decrease inextrinsic motivation levels after winning, (Weinberg, 1979) " It is as i.fthe person likes the game better for itself when he has evidence, throughwinning, that he is good at it. This fits with Decirs concept of anintrinsically motivating aetivity. (Since half of the particlpants losein most games, this finding brings up important questions for educators
l/1
trying to build positive lifelong habits of exercise in their students).
Physiology: It nray be that peoplebecause of how exercisre feels to them.factors was pointed ugr when Dishman andsuccessful in predicti.ng the variance inby utilizing the percnt body fat, bodyparticipant.
continue to exercise or quitThe significance of physicalGettman (1980) were mostadherence in an exercise program
weight, and SMI score of each
Affective and physiological changes occurring during and afterexercise may provi.de a means by which exercise can provide imrnediatereward or aversion to participants. Because vigorous exercise raises bodytemperature, atranquilizing effect uay occur, (de Vries, 1981). Vigorousphysical activity is consistently associated with a decrease in stateanxiety (the level of anxiety a person experiences at a given moment)(Morgan, 1979). Muscular exercise increases blood levels of hormones(Hartley, L975). And,
t5
drugs. colt, wardlaw, and Frantz (1981) have pointed out thar thoughbeta-endorphins administered centrally have been shornm to produce profoundbehavioral and analgesic effects, intravenous doses 1,000 to 10,000 timesas strong as levels measured in the blood after exercise have fai-led toproduce the same results, (Berger, et al, 1980; Gerner, et a1., 19g0).Moore (1982) reminds us that beta-endorphins are produced both by thebrain and the pituitary gland with those of the latter origin, outside theblood-brain barrier, being the ones that have been detected afterexercise. I^Ihat is occurring in the brain j-s not known. on the otherhand, beta-endorphin is i-mplicated in less profound changes in painsensitivity and mood that rnay play a role in the good feelings reportedafter exercise (Janal, Colt, Clark, & Glusman, 1984).
The existence of rhysiological and related psychological responses Loexercise may relate to the observation that people who could gain the mostfrom regular exercise ilre the least 1ikely to adhere. High weight andPercentage of body fat are predictors of nonadherence, (Dishman & Gettman,1980). Pati"ents recovrlring from heart attacks who di-splay the most damageto heart functioning hrrve been shovm to be least 1ike1y to adhere to atherapeutic exercise pr:ogram (Blumenthal, wi11ians, wallace, wi11iams, &Needels
' L982). If ext:rcise is painful or frightening, noncompliance can
be expected.
How exercise feels; to the participant blurs the line betweenparticipant and prograrl factors, because it depends so much on whatexercise is done and al: whaL intensity. For example, in one adherencestudy it was noted that: the observed pattern of adherence may have beendue to the exercise st;lrting too s1owly for the more fit participants
16
causing them to get bored and drop out (Gale, Eckhoff, Moge1, & Rodnick,1985). The wide varie:ty of individual abilities and preferences makesthis a likely source cf variance in adherence.
Social/environmental f actors
Being supported by others for exercising, both at home and in theexercise settingr has been related to adherence (Martin & Dubbert, 1982 ;King & Frederiksen, L984; Fetsch & Sprinkle, 1983). This facror inadherence introduces the beliefs, capabilities, and actions of peopleother than the participant. For example, the amount of support wives gavehusbands for preventive and Eherapeutic exercise for heart disease hasbeen explained by the health beliefs of the wives (Aho, 1977). Whileidentification with a group that is exercising can have posi-tive results(King & Frederiksen, 1984) problems in adherence can occur when the personleaves the goup either due to termination of a program, moving, ordiverging physical capabilities. Other social andenvironmental factors that have correlated with droppingprogram include smoking, inactive lei-sure-time pursuits,work (Oldridge, 1979).
out
and
of an exercisebluecollar
Exercise program factors
Fina1ly, the exer,:ise program itself has been studied as a factor incompliance. Given all of the factors outside the control of the programleaders, it makes sens: to have the exercise program be as positive aspossible. This includ,rs where, how, and when the participants exercise.
L7
Inconvenience of the exercise program location, inappropriate intensity ofthe exercise, and unfriendly or unsupportive manner of the programpersonnel have been cited as reasons for dropping out (Martin & Dubbert,1982; Andrew & parker, 1g7g). Finding the time and. discipline to exerci,seis challenge enough without it being difficult simply to get to the exercisesite. As previously rrentioned, the exercise intensity must match theneeds of the participzrnt; too 1itt1e phsyical challenge leads to boredomand too much to unnecrssary discomfort and possibly injury.
Summary
There are a numbe:r
good for people if the.rdifficult to adhere ro
reasons to beli.eve that regular exercise isit. Unfortunately, many people find it
exerci_se program.
of
do
an
Exerci"se adherencrr and medical treatment compliance are quitesi'milar, both relying trpon the patients or participants to follow theprescribed program' Fcr thi-s reason the riterature on medical treatmentcompliance has been reviewed here i.n an effort to broaden the backgroundfor considering factors in exerci.se adherence. compliance modelsi-ncluding the Health Belief Model, social Learning Theory, the utilityModel of Preventive Behavior, and the Relapse Moder were reviewed.
The Health Belief lfodel (Rosenstock, lg74) provides a basic frameworkfor viewing treatment er:mpliance, taking into account the patientrsperception of the risk, the efficacy of the preventive action, and thebarriers to taking preventive acti.on. Several other models of medical
18
comPliance showing dil:ferent ways to explain compliance refine and. expandon the Health Belief lvtodel. Social Learning Theory uses such concepts asbehavioral capability, expectaEions, locus of control, and self-efficacy;the Utility Model of I'reventive Behavior uses an economic theoreticalbasis to describe the utility (inmediate value in a broad sense) that theperson puts on each pcssible behavior; and the Relapse Model considerslapses i-n adherence tc be inevitable and considers how the patienE dealswith the lapse in maintaining the regimen. These models complement eachother and, taken together, provide a broad framework for betterunderstanding and study of treatment compliance and exercise adherence.
In the field of exercise the most successful prediction of adherenceto a program has come through a mix of physiological and psychologicalfactors; one proposed mix being percent body fat, body weight, and scoreon the Self-Motivation Inventory. As the most successful psychologicalmeasure in predicting and describing exercise adherence SMI and how itinteracts with other factors in adherence and compliance comprise the majorfocus of this study.
Objectives of the Study
In the Spring of 1984 the Center for Fitness Evaluation at WesternWashington UnirTersity contracted with the Atlantic Richfield Cherry PointRefinery in Ferndale, rrlasington to provide a comprehensive employeefitness program. The program was agreed to include (a) a completephysical assessment of each participant, (b) individual consultat.ions oncoronary heart disease risk profi-les, personalized exercise prescriptions,and dietary counseling, (c) supervised exercise sessions at WLIU, and (d)
19
monthly educational sesr;ions on a variety of health related topics ' The
physical assessments be;gan in May 1984 and were coBpleted by october 1984'
Exercise clases began i:n August 1984. The present study was ProPosed to
the wVlU Center for Fitness Evaluation and ARCO management in June of 1984
to examine exercise participation and adherence in the coupany sponsored
exercise program. The psychological data were collected for this study in
J-ate September Lg84, February 1985, and July 1985'
Specifically, the present study was Proposed to examine the role of
self-motivation in exercise adherence in a group of healthy, working
adults. It was hYPothesized that:
1. The Self-,Motivation Inventory (s!II) score coupled with percentbody fat and total weight would account for a significant
proportion oj: the variance in adherence'
2. The consl:ruct of Self-Motivation' defined by Dishman and
Gettman' (19130), would be supported as a major factor inexercise adh,rrence.
3. The Self-Motivation lnventory, (SMI) ' score would be
supported as a measure of Self-Itotivation'
20
Method
Subj ects
Thesubjectswere334maleandfemaleemployeesatanindustrialplant in Whatcom CounEy, Washi-ngton. (Gender breakdown varies by data set
and will be detailed later.) They were asked to take part in this study as
aPartofageneralhealthandexerciseProgrambeingprovidedbytheiremployer.
Materials
Exercise l"leasures
Exercise Repqlq-i#.1, (EXl) ' The first self-report of exercise (EXl)
was made at the Februa::y 1985 psychological testing and covered the period
from November l, 1984, to February 15' 1985' If the respondent had
exercisedatleastthreetiuesperweekforadurationofatleast15minutesateachsessio,nduringtheprevioustwoweeksheorshecheckedthat time period on the exercise rePort form (Appendix II' forrn 5) '
Exercise Report /12, (EXz). The second exercise report (EX2) was made
attheJunelgS5psychologiealtestingandcoveredtheperiodfromSeptemberI,1984,toMay15,1985'(AppendixIII'ExerciseReport)'ThesecondexerciserePort:wasinthesameformasthefirstexercisereportand used the same crit:eria for reporting a week of exercise '
2I
Exercise Report #3, (EX3) . To use self-reports made as closely to
Ehe reporting period as possible, Exercise
from the information collected in the firstIt covers the same 36 week period as EX2'
exercise rePort, EX3, ccmbines informationSeptember 1, 1984, to October L5,November 1, L984, to FebruarY 15
'
March l, 1985, to MaY 15, f9B5
Report /13 (Ex3) was calculatedand second exercise rePorts.
The calculated comPosite
EXI and EX2 as follows:
1984 (EX2),198s (Exl),
(Ex2).
Psvcholoeical Measures
Self l"lotivation Inventory (SMI) , (Dishman, Ickes, & Morgan, 1980) 'The SMI (Appendix I, fcrm 1) consists of 40 statements which are marked ona fi-ve part Likert scal.e from "highly characteristic of me" to "highly
uncharacteristic of me." Those who score high on the inventory are assumed
to have a higher level of self-motivation than those who score low' Iligh
internal consistency for the 40-item scale measured by Cronbachrs alpha
coefficient has been rtlported ( = .91) and repeated measurements over aperiod of I to 5 monthr; indicated stability of the scale (r's ranging from.86 to .92) (Dishman & rckes, 1981)'
Questionnai-re, STAI-T), (Spielberger, Gorsuch' & Lushene' 1970)' TheSTAI-T(AppendixI,forn2A;AppendixII'form28;AppendixIII'form28)is a self-report measure of general trait anxiety' The scale consists of
20 items which the subject marks as "almost alwaysr' (4), "often" (3) ',,sometimes,, (2), or "almost never" (1). A higher individual scale score
State-Trait AnxieEy Inventory, Trait, (Self-Evaluation
22
indicates higher trait anxiety'
Reasons for Starting a Structured Exercise Program (START) ' The
Reasons for starting a Structured Exercise Program forrn (Appendix t form 3) was
constructed by the auth.or and consists of a list of 17 possible reasons
for starting an exercise Program. Subjects who have started an exercise
program check as many sitatements as apply to thern (0 to 17) '
Reasons for Not St:arting a Structured Exercise Program (NST) ' The
Reasons for Not Startitrg a Structured Exercise Program form (Appendix
Irforrn4)wasconstrur:tedbytheauthorandconsistsofalistof19 possible reasons fo:: not starting an exercise Program' subjects who
have not st,arted 3I1 eXr3rcise program check as many of the statements as
apply to them (0 to 19).
ReasonsforContinuingaStructuredExerciseProgram.TheReasonsfor Continuing a Structured Exercise Program form (Appendix II' forrn 5 and
AppendixIII,form5)r,lasconstructedbyEheauthorandconsistsofalistof16possiblereasonsforcontinuinganexerciseprogram.SubjectswhoarecontinuingtoexelcisecheckasmanyoftheStatementsasapplytothen (0 to 16).
Reasonsfgl--pas-c('ntinuingaStructuredExercise?rogram'TheReasonsfor Discontinui-ng a sl:ructured Exercise Programform (APpendix II' form 6
and Appendix 1II, forrn 6) was constructed by the author and consists of a
list of 17 possible rrrasons for discontinuing an exercise program'
Subjects who had repo:rted sEarting an exercise program or starting and
continuinganexercis.:programandhavestoppedexercisingcheckaSmanyof the statements as apply to them (0 to 17) '
23
Phvsioloeical Measures
Bodv Weieht (WGT). BodY weightscale to the nearest 50 grams.
was measured on a Toledo beam balance
Height (HGT). Ilei13ht was measured with a stadiometer to the nearest.5 cm.
Maximal Aerobic Po.rer, (V02). Maximal Aerobic Power is the maximalrare at which oxygen can be consumed, in ml./min.lkg. (Ruppel, 1982) ' The
Bruce protocol (Bruce & Ilornsten, 1969) was perforured by all participants
using a Quinton motor driven treadmill for the assessment of maximal
oxygenconsuuption.Workwasinitiatedatstagelandeontinueduntilsubjectscouldnolongerparticj"pate.opencircuitspirometrymethodswere utilized for the collection of metabolic data. Respiratory gases
were conEinuously measu.red and recorded by the automatic Beckman Metabolic
Measurement Cart . AnaT.yzers \^7ere frequently calibrated with standard gas
mixtures. In vigorous activities of prolonged duration the aerobic system
supplies most of the erLergy used by the body making aerobic Power a major
factor (Center for Fitrress Evaluation, WWU' f984a) '
Bodv composition. Total body volume was determined by hydrostatic
weighing (Katch, Michar:l, and llorvath' 1967) and residual volume was
measured out of water l>y an oxygen diluEion technique in the bent forurard
seated posiEion (Wilmo:re,1969). Body fat was calculated from bodydensity using the siri formula (1956) and lean body weight was determined
by difference.a. Percent Percent bodY fat is the Percentage
24
of total body weight th:rt is fat.
obesity (CFE, 1984b).b. Lean body weight, (LBW).
couponents other than firt such as
It is the most direct measure for
Lean body weight
muscle, bone, and
is the weight bodY
water, (CFE, 1984b)
Flexibility. star:ic flexibility of the lower back, hips, and
shoulder was assessed irrdirectly through linear measurements of the
range of motion (Johnsorr, L977).a.Trunkflexion,(FLEXI).Trunkflexionrefersto
to sit and reach forwarimeasured in inches. The degree
depends on the length of the trunk extensor muscles of
also the hamstring muscles (CFE, 1984c) 'b. Trunk extension, (FLEX2). The trunk extension
measure of the range of the lower back in inches. Poor
this region can be an indication of potential lower back
of
the
the abilitytrunk flexionlower back and
test is aflexibility inproblems (CFE,
r984c).c. shoulder Extension, (FLEX3). The shoulder extension test
measures the range of flexion at the shoulder joint in inches, (CFE,1984c).
Blood pressure. Systolic and diastoli-c blood pressure was determined
at rest bY auscultatiorr.
ExpiratoryVolumesiandBreathingCapacity.ForcedvitalcapaciEywasperformed for the purpose of assessing forced expiratory volume as
described by Ruppel (11)82). To deleruine maximal breathing capacity,subjects exhaled forcefrrlly and rapidly as possible into a turbine driven
penumoscan for 12 secolrds. This value was reported as a minute capacity
by multiplying the numller of liters in 12 seconds by five'
25
a. Forced viral capacity, (FVC). Forced vital capacity is themaxi-mum amount of air that can be inspired and expired in one breath
(Ruppel, Lg82). Low va.Lues may indicate obstructed airways, cloggedbronchioles, or latent Lung disease (CFE, 1984d) '
b. Forced g*pi13tr)ry Volume, (FEV). Forced expiratory volume i-sthe amount of air that c,rn be expelled in one second (Ruppel , L9B2). Lowvalues indicate high airway resistance' or trapping of air in the 1ungs,
and may also be indicative of obstructive lung disease (Cff, 1984d).c. Maxj.mum Breathing capacr!yr__(49t-).- Maximum breathing capacity
is the maximum volume of air that can be breathed in 60 seconds (RupPel'
lg82). It is used to determine level of functioning of lungs andrespiratory muscles. Low values are generally indicative of weak
respiratory muscles or high airflow resistance caused by blocked airways
(cFE, 1984).
Serum Lipids: Total Cholesterof (TCttOL) , ttigh D"ns rotein
(IIDL), Low Density Lipcprotein (LDL), and Triglycerides (TRI).Blood samples for total. cholesterol, IIDL-C, and triglycerides were drar'rn
after a 12 hour fast from an antecuboidal vein' Total cholesterol conEent
was determined by the nrethod of Atlain, Poon, chan, Richmond, and Fu
(1g74). Iligh density f-ipoprotein was measured by precipitating all othercholesterol fractions with phosphotungstate-magnesium (Lipid Researchclinics Program, Lg75) leaving a supernatant which was measured for
cholesterol content. ltriglyceride levels \rere quantitatively assayed by
an enzymatic hydranalyr;is technique described by Beckuan Instruments
(1983). Low density l:Lpoprotein (LDL-C) was calculated according to themethod of Eriedewald, -evy' and Fredrickson (L972) '
26
Aooaratus for Phvsiological Measurement
The Center for Fitness Evaluation utilized the following aPparatus:
1. a motor driven treadmill to provide controlled exercise,
2. a face mask to collect expired air samples,
3. a Beckman metabolic cart expired air ana1-yzet to determine oxygen
and carbon dioxide concentrations of expired air'
4. a Pneumoscan turbine spirometer to determine pulmonary
ventilatlon.5. a Toledo beam balance scale to measure body weight to the nearest
50 graus,
6. a stadiometer to measure height to the nearest 0.5 centimeters,
7. a seat suspenc.ed from a calibrated Chatillion scale to measure
body weight submerged in water to determine body volume for computing
percent bodY fat,
8. a background j.nformation- form on which the subjects are asked tosupply demographi
27
Procedure
The present study rr7as an adjunct to a year-long employee health andfitness program. Two t Lmelines will be presented to clarify what happened
when in this study. First, the components and scheduling of the entire
health and fitness program (including this study) rsi11 be outlined' Then'a second timeline expan,ding on the components of the present study will be
provided.
Timeline for the health and fitness program'
i. winter 1984. The Director of the center for Eitness Evaluation
proposed an employee fitness program to management at the Atlantic
Richfield Companyts Cherry Point Refinery at Ferndale, Washington.'
2. Spring 1984. During the spring of 1984 ARCO contracted wiEh the
wl{u center for Fitness Evaluation to Provide a comprehensive fitness
evaluation program incl.uding: (a) complete physical assessments ofindividuals, (b) indivj.dual consultations on assessment results' diet' andexercise prescriptions (c) supervised exercise sessj-ons at wl,tru' and (d)
educational sessions olrer the course of a year'
3. May 1984. I:r.dividual fitness evaluations (PHYS) began and
continued throughout the sunmer and into the fall, the last evaluations
being completed in oct,rber. Shortly after the physical evaluation each
person received a personalized exercise plan which he or she could start
immediately or include in ongoing exercise '
4. June 1984. The present study l^7as Proposed to ARCO management by
28
way of the director to Ehe Center for Fitness Evaluation of study
adherence in the ARCO E:nployee Fitness Program'
5. August 1984. Exercise elasses for ARCO employees began at WWU.
6. September 1984. The content and timeline of this study was
agreed upon with the Enployee Relations Director at ARCO in early
September 1984. The first set of psychological questionnaires was
administered by ARCO Employee Relations Office personnel in late September
1984.
7. February 1985. The second psychological testing, abbreviated as
PSY2, was conducted at the ARCO Cherry Point Refinery'
g. May 1985. Th.e exercise classes at WWU concluded and Post-program
fitness evaluations beg,an and continued j-nto the fa1l.
g. June 1985. lihe final psychological testi-ng, abbreviated as PSY3,
was conducted at the AII'CO Cherry Point Refi-nery'
Tineline for the present study.
1. In September r.984 the first psychological Eesting (PSYI) was
conducted as follows:a.SubjectswererecruitedforthePreSentstudyatregulardepartment meetinl;s during work hours'
b. Those who chol;e to participate were asked to complete a set
of questionnaires. The set of questionnaires was constructed to
a11ow al1 employe(3s to partieipate by completing only those forms
that applied to t,:em. The packet of psychological questionnaires
29
used for the first testing (Appendix I) included:(1) a cover letter from the plant manager explaining thePurpose of the study and the voluntary nature of participation,
(2) a Proposed timeline for the study'(3) the Self-I4,otivation Inventory (SMI) to be cornpleted byall ParticiPants in the studY,
(4)theSTAI.T,labelledtheSelf-EvaluationQuestionnaire(STAI), to be completed by all partieipants in the study'(5) the Reascrns for Recently Starting a StructuredExercisePro6;ramform(STRT),tobecompletedbyindividualscurrently acl:ive in a structured exercise program'
(6) the Reasons for Not Starting a Structured ExerciseProgram forrr (NST), to be completed by individuals not currently
active in a l;tructured exercise program' and
(7) an AdjecEive Checklist to be completed by allindividuals completing the packet of questionnaires' (The Adjective
checklist r.7as part of another study of the ARC0 Exercise Project
and was included in this packet as a courtesy to that investigator) 'c. The completed packets were mailed to Lhe investigaEor at
wwu.
d. Participants were asked to provide their social security
numbersonEhepa'cketofquestionnairestoallowmatchingofdatawith subsequent claEa.
e. Participatin5; in the study rnras voluntary in two ways"
First, potential subjects had the option not to complete thequestionnaire.Secondly,theycouldcomplet,ethequestionnaires'but not provide Bhei'r social security number '
30
2. In February 1985 the second psychological testing (PSY2) was
conducted.
a. The testing procedure was identical to that used in
SepEember.
b. The test packet (Appendix II) included the followingquestionnaires:
(l) the STAI-T, in which the subjects were asked to indicatehow they had felt in the last two months (STAIA) '(2) the Reasons for continuing a structured ExerciseProgram and exercise report for the period from November 1, 1984,
to February 15, 1985 (CoNT) Eo be completed by those individualscurrently participating in a structured exercise program, and
(3) the Reasc,ns for Discontinuing a Structured Exerciseprogram form(.QUIT) to be completed by those who received a
physiological- assessment at wl{u and started a structured exercise
Program, but discontinued it '3. the third set of psychological test sessions (PSY3) took
place at the ARCO Cherr:y Point Refinery in June of 1985'
a. This set of trlsting sessions was conducted by the
investigator in a]r effort to receive as many packets of questionnaires
with idenEifying r3ocial security numbers as possible'
b.Thetestpacket(AppendixIII)includedthefollowing:(1)anexercisereportform(Ex2)coveri.ngtheperiodfromSeptember 1, 1984, to MaY 15, 1985'
(2)theSTAI-T,inwhichthesubjectswereaskedtoindicatehow they had felt in the last two months (STAIB) '(3)theReasonsforContinuingaStructuredExercise
Program form
in a struccompleting th(4) The ReasProgram form
recei-ved a Ph
structured e(5) an Adject(again this
c. The comPleted
from the jobsite
31
CONTA) To
exercise
be completed bY
program at the
individuals ParticiPatingtime theY were
f orm,
s for Discontinuing a Structured Exercise
QUITA), to be completed by individuals who had
iological assessment at wi'ru and started arcise program, but had discontinued it' and
ve Checklist to be completed by all participants
stionnaire was not part of the present study) 'orms from this testi-ng were collected and taken
the lnvestigator.