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Enabling 2-Wheeled Cycling for Youth With Down Syndrome

Halayko, Janine PT, MSc; Magill-Evans, Joyce OT, PhD; Smith, Veronica SLP, PhD; Polatajko, Helene OT, PhD

doi: 10.1097/PEP.0000000000000240
Research Reports

Purpose: To study the effectiveness of cognitive orientation to daily occupational performance (CO-OP) to teach motor skills to youth with intellectual disabilities.

Methods: Six youth aged 12 to 19 years participated in this study. A multiple baseline design was employed to evaluate distance and time cycled, and a pre-post-follow-up design was used to evaluate the effect on cycling skills mastered, cycling performance, and parent satisfaction.

Results: At follow-up, 5 of the 6 youth rode their 2-wheeled bicycles over 100 m in their communities (range, 103-1400 m) and demonstrated improved cycling skills and parent satisfaction.

Conclusions: The skills acquired by youth with Down syndrome using a CO-OP approach exceeded what has been reported in the literature. CO-OP offers a promising alternative to existing approaches for teaching 2-wheeled cycling to youth with Down syndrome.

A study of the effectiveness of Cognitive Orientation to daily Occupational Performance to teach motor skills to youth with intellectual disabilities.

Faculty of Rehabilitation Medicine (Ms Halayko, Dr Magill-Evans, and Dr Smith), University of Alberta, Edmonton, Alberta, Canada; Dalla Lana School of Public Health (Dr Polatajko), University of Toronto Neuroscience Program, Department of Occupational Science and Occupational Therapy and the Graduate Department of Rehabilitation Science, University of Toronto, Toronto, Ontario, Canada.

Correspondence: Janine Halayko, PT, MSc, Faculty of Rehabilitation Medicine, 3-48 Corbett Hall, University of Alberta, Edmonton, Alberta T6G 2G4, Canada (janine@j2h.ca).

Grant Support: This study was supported by a grant from the Women and Children's Health Research Institute, Edmonton, Alberta, Canada.

At the time this article was written, Janine Halayko was a student in the Faculty of Rehabilitation Medicine, Master in Rehabilitation Science, University of Alberta, Edmonton, Alberta, Canada.

The authors declare no conflicts of interest.

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INTRODUCTION

Riding a bike is a popular childhood leisure activity in Canada.1 For individuals with Down syndrome (DS), this skill is often elusive. Many children and youth work on 2-wheeled cycling skills for years; however, only 9.7% to 36% report being able to ride.2,3 The benefits of mastering this skill can be significant and include decreased time spent in sedentary activities, increased motivation to try other physical and sports activities, improved self-esteem and positive peer relationships.3–5

Limited research exists on how to teach cycling to children with DS. The iCan Bike program, formerly “Lose the Training Wheels,” is arguably the most widely known and researched. Training is provided over 75 minutes for 5 consecutive days,3,6 and a series of increasingly tapered roller wheels allow the balance demands of cycling to be gradually increased.4,7 The primary goals of iCan Bike are to “maintain a forward visual focus, pedal continuously, initiate handlebar steering actions, and consequently remain upright.”4(p53) Self-start and navigation are considered secondary goals. After the iCan Bike program, the majority of children (56%-100%) are able to independently ride straight distances of up to 30 m.3,6,7 However, in the study by MacDonald et al,6 though 73% of children with DS could ride a distance of 9 m, only 63% could brake and less than 20% could self-start.6 In addition, as the evaluation of “success” in the iCan Bike course has not been extended to evaluate the ability to ride in the community, the usefulness of the program in teaching cycling to promote participation remains unclear.

In contrast, 1 of the main aims of the cognitive orientation to daily occupational performance (CO-OP) approach is to generalize and transfer motor skills to a child's natural environment.8 The CO-OP method combines motor learning principles with behavioral and learning theories, and emphasizes the role of goal setting, problem solving, and other cognitive processes in the acquisition of movement skills. Described in detail by Polatajko and Mandich,8 the approach is composed of 7 key features: client-chosen goals, dynamic performance analysis, cognitive strategy use, guided discovery, enabling principles, parent involvement, and a specific intervention format. Researchers have demonstrated the success of the CO-OP approach in teaching a variety of skills including cycling to individuals with developmental coordination disorder,9–11 autism spectrum disorder,12 brain injury,13 and stroke14; none have reported using this technique with individuals with intellectual disabilities.

Many consider learning to ride a bike a rite of passage in childhood. For children with DS, modified bicycles seem to be the predominant strategy for teaching this skill,3–7 but little if any research has focused on other methods to enable cycling. This study aimed to determine the usefulness of the CO-OP approach for teaching children with DS to ride a conventional 2-wheeled bicycle.

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METHODS

Participants and Settings

Participants with DS between the ages of 8 and 19 years were recruited through a dedicated Web site, word of mouth, and an information bulletin sent out by a local DS society. Inclusion criteria were (a) the inability to ride a 2-wheeled bicycle, (b) access to a suitable bicycle, and (c) willingness to learn to ride. Exclusion criteria were neuromusculoskeletal conditions and health concerns or behaviors that might affect participation (by parent report). A university research ethics board approved all procedures. Written informed consent from parents and verbal assent from each youth were obtained.

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Participant Characteristics

Six youth (3 males, 3 females; mean age = 14.3; age range: 12-19 years) participated. All lived at home and none attended the same school. Intelligence quotient (IQ) scores were obtained from the most recent psycho-educational assessment provided by parents and indicated that 5 children had a moderate cognitive delay (IQ = 40-53; mean for participants = 44.8). One participant had never received psycho-educational testing. Participants were also asked whether or not they wanted to learn to ride a 2-wheeler; 3 youth said no, despite assenting to participate in the study. Characteristics of the participants and whether they wanted to learn to ride are presented in Table 1.

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Setting

All baseline and intervention sessions as well as 2 follow-up sessions occurred in the parking lot, adjacent shallow hill, and trail system of a city park. Parents determined the location of the 3 remaining follow-up sessions.

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Experimental Design

A single-case multiple baseline design across participants, with a follow-up probe, was used to evaluate distance and time cycled. As required in this design, the start date of the intervention was staggered so that participants could serve as both their own controls and as controls for others.15,16 Parent preference and vacation times determined subsequent scheduling. A pre- and post-test design examining skill achievement, community cycling participation, and parent satisfaction with cycling skills was used to determine the clinical validity of the intervention.

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Materials

Each participant brought his or her own bicycle and helmet to the sessions. Optional safety equipment provided for participants included kneepads, elbow pads, and a wingman support harness. In 1 case (participant 3), a support handle was used; this was designed and installed by his father.

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Dependent Measures

Time and Distance Cycled. The primary dependent variables were distance and time cycled, measured from where the participant put both feet on their pedals and/or external support was removed (whichever came last) to the point when 1 foot contacted the ground and/or external support was provided (whichever came first). Two 7-m lines taped to the parking lot surface were marked at 1-m intervals to facilitate measurement. Distances over 7 m were measured using a 4-inch metric measuring wheel. Distances less than 7 m and the corresponding riding times were measured by video analysis, as were the times for distances over 7 m. Within each baseline and follow-up session, the longest distance was recorded, as was whether riding was achieved by stationary launch, dynamic launch, or without assistance.

Cycling Skills. A Cycling Skill Checklist (developed by and available from the first author) was used to give more specific information relating to cycling skills mastered. The skill checklist consisted of 20 cycling tasks divided into 4 sections: bike manipulation and stationary skills, prepedaling dynamic skills, and beginning and advanced riding skills. Each task was given a score of 0 to 5, with 0 representing a refusal or inability to complete the skill, and 5 representing independence in the skill. An observational score of up to a maximum of 100 was obtained. The skill checklist was created in consultation with 2 experienced cycling instructors with adapted physical education backgrounds at an unrelated agency offering cycling classes for children with disabilities. Validity of the checklist has not been formally assessed.

Parent Ratings. Before beginning the study, using the format of the Canadian Occupational Performance Measure (COPM),18 all parents were asked how important it was to them that their child learn to ride, how they viewed their child's performance, and how satisfied they were with their child's cycling ability. Importance placed on cycling and the pre- and post-intervention parent ratings of performance and satisfaction are presented in Table 2.

Interobserver Agreement. Skill checklist ratings, time cycled and distance measurements less than 7 m were determined by video observation. Forty percent of baseline and follow-up sessions for each participant were randomly selected and rated by a second rater blinded to the study phase, and interrater reliability analyses using weighted kappa and intraclass correlation were performed to determine consistency among raters.17 Interrater reliability for the skill checklist was very good (κw = 0.826; P < .001; 95% confidence interval [CI] = 0.783-0.869). Reliability for both distance and time measurements was excellent (intraclass correlation coefficient (3,1) = 1.0; P < .001; 95% CI = 0.999-1).

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Intervention Description and Treatment Fidelity

CO-OP Modifications. Two of the key features of the intervention were modified a priori. First, with respect to client-chosen goals, only 1 goal—cycling—was addressed, and this was chosen by the parents rather than by the youth. The time was also shortened from 10 to 8 one-hour sessions to reflect a single goal. The youth did choose subgoals. Second, regarding involvement of significant others, neither in-class parent involvement nor extra practice was required. However, in most cases, parents stayed to watch and/or participate, and asked for ideas for what they could work on at home.

Anticipating that other features of CO-OP may require modification, a log was kept and analyzed at the study completion. The enabling principles of CO-OP were used more than is typically described in the literature. Examples include the use of extrinsic reinforcements, direct teaching techniques, visuals to supplement task knowledge, making choices obvious through modeling, prompting using physical cues, chaining to learn a sequence of skills, and fading to work toward independence. These strategies helped teach basic knowledge involved in riding a bike or to allow the youth to discover solutions themselves. All of the other features of CO-OP were followed.

Baseline. The primary dependent variables of distance and time cycled were measured on 5 occasions. As none of the children could cycle, repeated early assessment would add unnecessary frustration for the youth and their parents. Therefore, they were given the option of completing 2 baseline probes on the same day. In these instances (for 4 participants), the 5 probes were completed over 3 separate days. When 2 probes were done on the same day, trials were separated by at least 10 minutes except for participant 6, who waited an average of 5 minutes between attempts. The length of time spent in the baseline phase ranged between 6 and 42 days (median = 12.5; mean = 18.3). All but 1 family (participant 3) reported no practice during baseline.

Both a stationary launch and a dynamic launch were attempted at baseline as no participants were able to start riding independently. For a stationary launch, the rider started with 1 or both feet on the pedals. The person supporting the rider took a maximum of 3 steps before letting go of the bike seat, harness, or bike handle. The stationary launch was attempted 3 times, and the longest riding distance entered. For a dynamic launch, the instructor walked along with the rider (more than 3 steps) and external support was only removed if the child was relying very little on the instructor to remain balanced. If the dynamic launch was not possible because of safety reasons, this was noted. The Cycling Skills Checklist was also completed at baseline.

Intervention. Each participant attended 7 to 8 separate intervention sessions (mean = 7.8) over 24 to 47 days (median = 35.5; mean = 35.7) as per parent scheduling preferences over the summer months. The length of intervention sessions was also variable, though averaged 40 to 50 minutes. Although 60 minutes was allotted for each session, late arrivals, unsuitable weather conditions, and lack of participant engagement sometimes caused the sessions to start late or to end early. Video recording errors also occurred, resulting in portions of the intervention not being captured. The shortest intervention session (session 7, participant 3) lasted 9 minutes; after a successful ride the youth declared he was “all done.” After this session, he moved on to the follow-up phase as he was able to start and stop independently, could turn and maneuver the bicycle and could ride independently for at least 1 minute. His skills corresponded with a score of 4 or 5 (maximum = 5) on 17 of the 20 tasks of the skill checklist, for a total score of 88/100. All other youths moved on to the follow-up phase when they had completed the full 8 intervention sessions.

The global CO-OP strategy of goal-plan-do-check was taught in the first intervention session and reinforced or re-introduced as necessary each subsequent intervention session. At the beginning of each session, participants were prompted to choose a subgoal or focus (eg, participant 1 consistently asked to work on “starting” and participant 5 “balancing”). When a youth could not independently come up with a subgoal, they were given choices of skills on the basis of the dynamic performance analysis of where their cycling performance was breaking down. Participants were then guided to discover plans to overcome their performance problems (eg, for riding in a straight line, they were asked if they would like to try the plan of pedaling fast or slow), and their choice was practiced before checking if the plan chosen was effective. Visual cues and reinforcements (eg, using pictures for choice making, getting the tires wet to show the trajectory of the bike at different speeds, and reviewing videos) were used as necessary to help participants decide on a goal or plan, or to check their plan's effectiveness. In this way, the youth were involved in all aspects of the decision-making process.

Follow-Up. Participants attended 5 follow-up sessions over 11 to 28 days (median = 14; mean = 17) with timing based on parent request. All youth except participant 6 attended on 5 different days; participant 6 completed the 5 probes over 3 days with a similar break between measurement sessions as during baseline. Distance and time measurement procedures were also the same as in baseline, though when independent launch had been achieved, only this method was measured. As most participants had progressed to independent cycling by follow-up, more advanced cycling skills (eg, self-starting, navigation, and hills) were assessed using the Cycling Skills Checklist. The time between the first baseline and the final follow-up session was 72 to 112 days (median = 79.5; mean = 87.7).

One month or more after the last follow-up session, a parent questionnaire was completed to obtain feedback about cycling in the community, barriers to cycling (if any), and the form of cycling (eg, conventional or adapted bicycle) seen as most functional. Parent ratings of satisfaction with their child's cycling abilities and of their child's performance were also obtained.

Therapist Training and Treatment Fidelity. Sessions were led by a pediatric physiotherapist with 12 years of experience teaching cycling and with training in the use of CO-OP from the developers of the approach. Feedback from 1 of the developers was also given during the study via joint video analysis and regular discussions. For the purposes of fidelity, 1 intervention session for each child was selected and fidelity determined by video analysis by a second rater blinded to the intervention session. Intervention sessions were randomly stratified to allow rating of 6 different sessions (13% of sessions). Fidelity to the principles of CO-OP intervention was 89%; without considering discussion of homework, fidelity was 98.3%.

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RESULTS

The primary outcome measures of distance and time cycled were plotted on a graph and analyzed for trend, level, and variability (Figure 1). Where time and distance points correspond exactly on the graph (and are not close to 0), the participant's average speed was 3 m/s. Overall, the participants' speed of riding ranged between 2.4 and 4.8 m/s (median = 3.1; mean = 3.2). During the intervention phase, time was measured via video analysis of the probes taken at the beginning of each session; distance was not recorded during this phase. The Non-overlap of All Pairs (NAP) method19 was also used to compare the differences between baseline and follow-up measures.20 The secondary outcome measures of skills mastered and performance and satisfaction ratings were administered pre- and post-intervention, compared using the Wilcoxon matched pairs test, and analyzed using SPSS (version 21).

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Time and Distance Cycled

None of the participants was able to ride more than 1 m entering the study. For all but 1 participant, the data demonstrated stability at baseline, with 5 participants cycling only between 0 and 2 m throughout the 5 baseline sessions. The distances cycled by participant 3 showed an upward trend; on the fifth baseline session, he rode 30 m with a dynamic launch. On follow-up, 5 participants were able to ride a minimum distance of 31 m (11 seconds), and each rode over 100 m at least once. One youth (participant 6) remained unable to ride. The NAP indices were calculated at 1.0 for the 5 riders and 0.74 for the nonrider. Combined, this yielded an index of 0.96 (P < .001; 90% CI = 0.699-1.214), corresponding to a large effect size in multiple baseline research.21 This significant effect is also reflected in the obvious positive changes in trend and levels for all but participant 6.

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Cycling Skills

Total scores (of 100 possible maximum) for all participants on the skills checklist ranged from 24 to 45 (median = 35; mean = 35.1) for baseline sessions and 38 to 99 (median = 83; mean = 73.6) on follow-up. The number of skills (of 20) that participants were able to perform without physical assistance (ie, a score of 3-5 on the skill checklist) is presented in Figure 2 and ranged from 4 to 8 (median = 7; mean = 6.7) for baseline sessions and 7 to 20 (median = 18; mean = 15.8) on follow-up. Skills varied both within and between sessions, and were dependent on the environment (eg, weather and length of trail) and the participant (eg, engagement). This variability is shown in Figure 3. Although all participants could brake, only those who were able to coast independently (ie, push and glide with feet off of the pedals) could self-start. A significant effect was evident between the average baseline and follow-up measures of cycling skills (Z = −2.20; P < .05).

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Parent Ratings

Before beginning the study, the parent ratings of their children's cycling performance (median = 1; mean = 1.5) and their satisfaction with this performance (median = 1; mean = 2.8) on the COPM18 were generally low. None of the 6 youth were able to ride without significant encouragement and physical support. After intervention, the parental ratings ranged from 1 to 8 for performance (median = 7; mean = 6) and from 1 to 10 for satisfaction (median = 10; mean = 8.3). These changes were statistically significant for performance and satisfaction (Z = −2.07, P < .05; Z = −2.03, P < .05, respectively).

The father of participant 3 indicated that his son had practiced cycling regularly from the onset of the study and the parents of participants 2, 4, and 5 reported that they began practicing once their children demonstrated increased independence with cycling skills. At the 1-month follow-up, the parents of these same 4 youth indicated that their children would continue to use a 2-wheeled bicycle. The parents of participants 1 and 6 who reported that they had rarely (30 minutes) or never practiced respectively, were uncertain whether 2-wheeled cycling would be used in the future. Although participant 1 could ride, her mother reported that 2-wheeled cycling was not feasible for several reasons: the road was too busy to safely ride, her daughter refused to ride on a sidewalk not bordered by grass on both sides, and they had no easy trails around their home.

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DISCUSSION

Existing studies of cycling instruction for individuals with DS focused mainly on the achievement of straight riding over a distance of up to 30 m using adapted bicycles.3,6 The other skills necessary for successful community cycling (eg, braking, navigation, and self-starting), the quality of the cycling (eg, consistency and level of supervision required), and the translation of the acquired skills to cycling participation have not been adequately addressed.

In the current study, exposure to cycling (ie, participation in the baseline phase) resulted in improvements in cycling skills for some (Figure 3). However, this did not translate to increased distance cycled for any but participant 3 who had been practicing daily with his father. Although participant 3 was able to cycle a distance of 30 m by the end of baseline, he remained unable to turn, start, or stop his bicycle and was reportedly still unable to participate in community cycling.

The use of a modified CO-OP approach during the intervention phase led to 3 of the 6 youth (participants 1, 3 and 5) being able to independently navigate, stop, and self-start. Participant 2 required only minimal assistance with starting as her bike was slightly too tall for her, and participant 4 required closer supervision for safety during navigation skills. At follow-up, these 5 youth (83% of participants) were consistently able to cycle a distance of 30 m using standard equipment and to stop independently. Significant improvements were also seen in all subjective measures (skills checklist, COPM parent ratings). Four parents reported that their children's cycling skills were maintained or improved 1 month after the study concluded.

The parents of 2 youth who did not learn to ride or did not continue riding were the only ones who reported little practice at home. Parents being unable to help their child with cycling was identified as 1 of the barriers to cycling mastery, as were an inaccessible environment, unmodified bicycles, and lack of follow-up support.22 Although the environment had an effect on participant 1 in her home environment, most parents reported feeling comfortable continuing to progress their children's skills on their unmodified bicycles after the CO-OP intervention.

The fact that most participants learned to ride without access to an adapted bike and were able to transfer this skill to their communities highlights the efficacy of a cognitive approach in facilitating not only the activity of riding but also cycling participation. External supports such as the harness or the bar attached to the bike made it easier to shape the skill of balancing and to fade assistance. By using visuals to enhance understanding and behavioral reinforcements to increase engagement, it was possible to use CO-OP with this population; these same strategies have been shown to be helpful when using CO-OP with children with autism spectrum disorder.12 Reviewing videos or sequencing steps using pictures helped to check for understanding. The results are a powerful reminder of the importance of involving our clients in the intervention process.

In pediatric physiotherapy, CO-OP is not yet well used; however, the positive results seen in terms of participant engagement in the intervention and the ease of generalizing the strategies to the community make it an extremely useful intervention method. As this is the first study investigating both the use of conventional bicycles and the use of CO-OP with this population, further research is required to confirm these results. However, as this study demonstrates a larger percentage of participants with DS riding independently over longer distances, mastering a variety of skills on the bike and participating in community cycling than has been shown in other studies, the use of CO-OP is certainly worth exploring.

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Limitations and Future Directions

A limitation of the study is that parent involvement and practice was not considered closely. This factor has been identified as affecting cycling participation in other studies22; however, further investigation is necessary to determine the specific barriers to participation using a CO-OP approach, and whether these barriers differ from other approaches.

Although the results of this study indicate a strong effect of the intervention within a single-case research design, more complex study designs are necessary to continue building support for CO-OP when teaching 2-wheeled cycling or other skills to children and youth with intellectual disabilities. A study that more closely adheres to the key features of CO-OP (eg, child-chosen goals) would be beneficial for determining its use with this population. Future research should include group studies with larger numbers, a greater diversity of participants and a control group. Comparing the effectiveness of a CO-OP intervention against other cycling teaching techniques (eg, iCan Bike) would also be beneficial.

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ACKNOWLEDGMENTS

The authors acknowledge the support of the Edmonton Public School Board and the Edmonton Bicycle Commuters Society.

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adolescence; bicycling; Down syndrome; female; human; male; motor skills; teaching method

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