USING TOKEN REINFORCEMENT TO INCREASE WALKINGFOR ADULTS WITH INTELLECTUAL DISABILITIES
HALEY KRENTZ, RAYMOND MILTENBERGER, AND DIEGO VALBUENA
UNIVERSITY OF SOUTH FLORIDA
The purpose of this study was to evaluate the effectiveness of token reinforcement, using anABAB reversal design, for increasing distance walked for adults with mild to moderate intellec-tual disabilities at an adult day-training center. Five participants earned tokens for walking 50-mlaps and exchanged tokens for back-up reinforcers that had been identified through preferenceassessments. Token reinforcement resulted in a substantial increase from baseline in laps walkedfor 4 participants.
Key words: adults, intellectual disability, physical activity, token reinforcement, walking
Physical inactivity can contribute to serioushealth problems, including cardiovascular dis-ease, cancers, diabetes, hypertension, andstroke (Centers for Disease Control and Pre-vention [CDC], 2015b). In the United States,only about one in five adults meets physicalactivity guidelines. Furthermore, a majority ofadults with intellectual disabilities (ID) do notmeet physical activity recommendations(Peterson, Janz, & Lowe, 2008). Conse-quently, increasing physical activity in indivi-duals with ID is an important class of behaviorto target.Several studies have used token reinforcement
to increase exercise with this population. Ben-nett, Eisenman, French, Henderson, and Shultz(1989) administered tokens for pedaling a pre-determined number of rotations on a stationarybike; tokens were exchanged later for back-upreinforcers. Pedaling increased with the inter-vention and decreased when the token economywas withdrawn. Croce and Horvat (1992) deliv-ered tokens at the end of each experimental ses-sion contingent on meeting the duration orfrequency of an exercise from the previous
session, with additional tokens provided forexceeding the performance of the previous ses-sion. Although no baseline data were collected,this study showed increases in exercise duringintervention. Todd and Reid (2006) used self-monitoring, verbal cueing, encouragement, andedible reinforcement to increase snowshoeing,walking, and jogging. This multicomponentintervention resulted in an increase in laps forall participants; however, the authors failed toestablish a functional relation between the inter-vention and physical activity because they didnot use an adequate experimental design.Although a few studies suggest that token
reinforcement can increase physical activity inadults with ID, only one study demonstratedadequate experimental control. Therefore, thepurpose of this study was to assess the effective-ness of token reinforcement for increasing dis-tance walked for adults with ID who attendedan adult day-training center.
METHOD
Participants and SettingFive men, ages 34 to 67 years with mild to
moderate ID, participated in the study. Noparticipants had any physical disabilities thatprevented walking. Each participant’s bodymass index was used to categorize him as
Correspondence should be addressed to RaymondMiltenberger, Department of Child and Family Studies,University of South Florida, Tampa, Florida 33612(e-mail: [email protected]).doi: 10.1002/jaba.326
JOURNAL OF APPLIED BEHAVIOR ANALYSIS 2016, 49, 745–750 NUMBER 4 (WINTER)
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overweight or obese according to standardizedcriteria (CDC, 2015a). John, a 67-year-oldwith moderate ID, was obese and diabetic.Paul, a 53-year-old with mild ID, was over-weight, diabetic, and had a doctor’s recommen-dation to engage in physical activity each day.Jerry, a 37-year-old with mild ID, was obeseand a heavy smoker. Elton, a 46-year-old withmild ID, had previously participated in a walk-ing group. Frank, a 34-year-old with moderateID, worked mowing lawns on a crew twomornings per week. All participants completedthe Physical Activity Readiness Questionnaire(Thomas, Reading, & Shephard, 1992) to con-firm that they had no health risks associatedwith engaging in walking. All participants weretheir own legal representatives, provided writtenconsent, and vocally stated they wanted to par-ticipate. The participants were told that theycould leave the study at any time.This study was conducted at an adult day-
training center in Florida, where adults withvarying disabilities learned functional skills andengaged in work activities with staff supervi-sion. Participants arrived at the center at8:30 a.m. and left at 2:30 p.m.
MaterialsCones were used to mark a 50-m lap
around which the participants walked. The lapwas in the same location for all sessions in anoutside, covered corridor where staff providedconstant supervision. One personalized giftbag for each participant was hung on a fencenear one end of the lap so earned tokenscould be deposited after each lap. The back-up reinforcers earned throughout the study arelisted in Table 1.
Response Measurement, InterobserverAgreement, and Treatment IntegrityThe dependent measure was the number of
50-m laps walked in 1 hr, tallied by theresearchers on a data sheet. A lap was defined
as walking from one cone around the othercone and back. For 38% of the sessions, theresearcher and an independent observer (firstand third authors) recorded the number of laps.Interobserver agreement was calculated bydividing the smaller number of laps by the lar-ger number of laps and converting the result toa percentage. Agreement was 99.6% (range,96% to 100%) for John, 99.6% (range, 96%to 100%) for Paul, 100% for Jerry, 99.8%(range, 97% to 100%) for Elton, and 99.9%(range, 99% to 100%) for Frank.
ProcedureAll sessions occurred from 9:00 a.m. to
10:00 a.m. on weekdays. An ABAB design wasused to evaluate the effectiveness of token rein-forcement for increasing distance walked.Baseline. At 9:00 a.m., the researcher asked,
“Who wants to walk today?” The participantswho said they wanted to walk followed theresearcher to the walking lap. Sessions lastedfor 1 hr or until the participant said he wasdone walking for the day. Participants wereallowed to take a break at any time during thesession. No tokens or praise was delivered forwalking. The researcher stayed at the start ofthe lap and said the lap number each partici-pant started (e.g., “This is your third lap.”) in aneutral tone of voice.Preference assessment. During baseline, the
researcher interviewed the staff and participantsto identify what tangible or edible items theparticipants preferred. A multiple-stimulus-without-replacement preference assessment wasconducted using the stimuli identified in theinterviews to establish a hierarchy of preferencefor these items (DeLeon & Iwata, 1996). Thisassessment was repeated three times for eachparticipant, with at least 5 min between eachassessment. The token exchange rate was basedon each individual’s baseline levels of walkingto ensure that each participant had a similaropportunity to earn reinforcers. The exchange
HALEY KRENTZ et al.746
rate used in the first token-reinforcement phasefor the high-preference item was the averagenumber of laps walked during baseline (exclud-ing days with zero laps walked) multiplied byfive; the exchange rate for the low-preferenceitem was the baseline average for laps walked.During the second token-reinforcement phase,the prices were increased for some participantsbased on performance in the first interventionphase. The potential reinforcers were unavaila-ble to the participants at the center during theintervention phase; however, they could accessthem outside the center.
Token reinforcement. After participantscompleted the preference assessments, theresearcher brought them to the start of the lapand showed them their individualized bags.The researcher then demonstrated a lap andplaced a token in the bag. Each participantrehearsed a lap by walking around the lap andplacing his token in his bag.The start of each session was identical to
baseline, except that the researcher told the par-ticipants that they would be given a token aftercompleting each lap and that the tokens couldbe exchanged for their preferred items. The
Table 1Items Selected in the Preference Assessment, Percentages of Reinforcers Chosen, and Total Cost of Reinforcers Across
Participants
ParticipantItems chosen in preference assessment with
token exchange rates (TP 1, TP 2)% of reinforcerselection in TP 1
% of reinforcerselection in TP 2
Total cost ofreinforcers
John Book (75, 75)CD (65, 65)Nutella sticks (60, 50)Uno (45, 45)Word search (35, 35)Diet soda (20, 25)Gatorade (15, 25)
Diet soda: 75Gatorade: 16.7Uno: 8.3
Gatorade: 96Diet soda: 4
$29 ($0.91 perday)
Paul CD (125, 135)Coffee mug (100, 110)Diet soda (75, 70)Gatorade (25, 50)Gatorade chews (50, 25)
Gatorade: 81.8CD: 9Gatorade chews: 9
Gatorade: 75Gatorade chews: 25
$10 ($0.59 perday)
Jerry CD (100, 110)Pokémon card pack (TP 2 only, 110)Coffee mug (90, 105)Light-up ball (85, 100)Bracelets (60, 80)Uno (50, 75)Pokémon card (TP 2 only, 60)Gatorade chews (30, 50)Nutella sticks (25, 35)Wildberry bar (20, 25)
CD: 40Uno: 20Light-up ball: 20Coffee mug: 20
Pokémon card pack:18.8
Pokémon card: 6.3Ball: 6.3Nutella sticks: 43.8Wildberry bar: 25
$30 ($0.94 perday)
Elton Book (320, 320)Water bottle (256, 250)Light-up ball (192, 200)Word search (128, 130)Flavored water (64, 65)
Book: 50Ball: 50
Book: 100 $52 ($1.63 perday)
Frank CD (125, 320)Book (100, 300)WWE (TP 2 only, 200)Water bottle (120, 200)Gatorade (75, 175)Light-up ball (50, 100)Cards (25, 65)
Book: 50CD: 50
Book: 16.7WWE: 50Water bottle: 16.7Light-up ball: 16.7
$40 ($1.74 perday)
Note. TP = token phase.
747TOKEN REINFORCEMENT TO INCREASE WALKING
researcher then announced, “You guys can startwalking now!” The researcher handed tokens toparticipants one by one as they completed alap, and participants then placed them in theirpersonalized bags. In addition, the researcherand staff member made encouraging statements(e.g., “Great job! You are walking for [rein-forcer]! Keep up the hard work!”) for 5 s afterparticipants placed a token in the bag at theend of a lap and every other time the partici-pant reached the opposite side of the lap. Atthe end of the hour, the researcher and staffmember counted the tokens and told the parti-cipants how many laps they had walked. Theparticipants chose to either exchange tokenseach day after the walk or accumulate thetokens to earn a more costly item at alater time.
Social ValidityA questionnaire was administered to partici-
pants and the staff at the center to assess theiropinions of the walking program (availablefrom the second author). The questionnairesconsisted of questions about activity levelsbefore and after participating in the programand about the program’s acceptability.
RESULTS
Preference assessment results are displayed inTable 1. Items selected in the preference assess-ment, percentage of reinforcers chosen in thetoken-reinforcement phases, and the cost ofreinforcers per participant are shown.Figure 1 depicts laps walked per session
across all phases for all participants. The firsttoken-reinforcement phase resulted in a notice-able increase in laps for four of the five partici-pants (John, Paul, Jerry, and Frank). After thereturn to baseline, the laps decreased for all fiveparticipants to around previous baseline levelsor below (for Elton). When token reinforce-ment was implemented again, all five partici-pants substantially increased their laps. Days in
which the participants were at the center butchose not to walk are depicted as 0 laps forthat day.Participants and a staff member completed
the social validity questionnaire on the last dayof the study. Questions were scored on a5-point rating scale on which 1 = strongly disa-gree and 5 = strongly agree. The participants’mean scores were 4.8 (I walk more now thanbefore), 4.6 (The walking program was enjoya-ble), 4.8 (I feel more physically active now thanbefore), and 4.6 (I will continue walking). Thestaff members’ mean scores were 5 (feasibility),4 (ease of implementation), 5 (valuable for par-ticipants), and 5 (would continue theprogram).
DISCUSSION
This study demonstrated that the token-reinforcement program (consisting of tokens,praise, and back-up reinforcers) increased dis-tance walked for adults with ID. Despite someoverlap in data between phases, treatmenteffects are clear, and experimental control isdemonstrated with the replication of theseeffects with four of the five participants (John,Paul, Jerry, and Frank). Although participantsreported in the social validity survey that theywould continue to walk, the decrease in activityduring the return to baseline suggests that theincreased activity did not maintain in theabsence of token reinforcement.The results of this study are consistent with
research from Bennett et al. (1989), Croceand Horvat (1992), and Todd and Reid(2006) indicating that providing token reinfor-cers contingent on exercising increases physicalactivity for adults with ID. The current studyadds to the literature by using a strongerexperimental design and longer exercise ses-sions (1 hr), assessing social validity of theintervention, collecting treatment-integritydata, conducting a preference assessment toidentify potential reinforcers and to set the
HALEY KRENTZ et al.748
token exchange rate, and including a detailedaccount of the back-up reinforcers selectedand their price.
Unlike Todd and Reid (2006) and Croce andHorvat (1992), this study demonstrated a func-tional relation between the token-reinforcement
05
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John
BL Token Reinforcement Token ReinforcementBL
01020304050607080
Paul
0
10
20
30
40
50
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70
Jerry
0102030405060708090
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Lap
s
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Figure 1. Laps walked per session for each participant. Triangles indicate days in which the participants arrived lateto the walking session.
749TOKEN REINFORCEMENT TO INCREASE WALKING
intervention and distance walked, as demon-strated in the ABAB design. The 1-hr sessionduration in this study is similar to that of Croceand Horvat, which is longer than in previousstudies; Bennett et al. (1989) conducted 15-minsessions, and Todd and Reid conducted 30-minsessions.The total cost for each participant’s reinfor-
cers ranged from $9 to $53 ($0.59 to $1.74per day). Although this study used a preferenceassessment to determine individual reinforcersand to determine the token exchange rate, it isunclear whether it was more effective thanother studies that used rewards not identifiedwith a preference assessment. Future researchshould focus on determining which of theseapproaches is more effective and efficient toincrease exercise behaviors. Another limitationis that stating the lap numbers in a neutral tonein baseline may have been a form of attentionthat influenced baseline performance. Also, theinterobserver agreement data collection mayhave been affected because the second observermay have heard the lap number being stated bythe researcher. Despite these limitations, thetoken-reinforcement program had high socialvalidity and was an effective and easy-to-implement intervention to increase physicalactivity in individuals with ID.
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Centers for Disease Control and Prevention. (2015a).Body mass index. Retrieved from http://www.cdc.gov/healthyweight/assessing/bmi/index.html
Centers for Disease Control and Prevention. (2015b). Physi-cal activity and health. Retrieved from http://www.cdc.gov/physicalactivity/basics/pa-health/index.htm
Croce, R., & Horvat, M. (1992). Effects of reinforcementbased exercise on fitness and work productivity inadults with mental retardation. Adapted PhysicalActivity Quarterly, 9, 148–178.
DeLeon, I. G., & Iwata, B. A. (1996). Evaluation of amultiple-stimulus presentation format for assessingreinforcer preferences. Journal of Applied BehaviorAnalysis, 29, 519–533. doi: 10.1901/jaba.1996.29-519
Peterson, J. J., Janz, K. F., & Lowe, J. B. (2008). Physicalactivity among adults with intellectual disabilities liv-ing in community settings. Preventive Medicine, 47,101–106. doi: 10.1016/j.ypmed.2008.01.007
Thomas, S., Reading, J., & Shephard, R. J. (1992). Revi-sion of the Physical Activity Readiness Questionnaire(PAR-Q). Canadian Journal of Sport Sciences, 17,338–345.
Todd, T., & Reid, G. (2006). Increasing physical activityin individuals with autism. Focus on Autism and OtherDevelopmental Disabilities, 21, 167–176. doi:10.1177/10883576060210030501
Received October 22, 2015Final acceptance January 27, 2016Action Editor, Matt Normand
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