A physical activity coaching intervention can increase and maintain physical activity and health-related outcomes in adult ambulatory care patients in a regional hospital: the Healthy4U-2 randomised controlled trial

Background: The Healthy 4U-2 study sought to evaluate the effect of a twelve-week, physical activity (PA) coaching intervention for changes and maintenance in PA, anthropometrics and health-related outcomes in adults presenting to an ambulatory hospital clinic. Methods: One hundred and twenty insuciently active adults were recruited from an ambulatory hospital clinic and randomised to an intervention group that received an education session and ve 20-minute telephone sessions of PA coaching, or to a control group that received the education session only. ActiGraph GT3X accelerometers were used to measure moderate-to-vigorous physical activity (MVPA) at baseline, post-intervention (3 months) and follow-up (9 months). Secondary outcome measures (anthropometrics, PA self-ecacy, healthrelated and quality of life) were also assessed at the three time points. Results: At baseline, the mean age and body mass index of participants were 53 ± 8 years and 31 ± 4 kg/m 2 , respectively. Relative to control, the intervention group increased objectively measured MVPA at post-intervention (p<0.001) and 9 months follow-up (p<0.001). At the 9-month follow-up the intervention group completed 22 min/day of MVPA (95% CI: 20 to 25 min/day), which is sucient to meet the recommended PA guidelines. The intervention group exhibited benecial changes in body mass (p<0.001), waist circumference (p<0.001), body mass index (p<0.001), PA self-ecacy (p<0.001), and health-related quality of life (p<0.001) at the 9-month follow-up. Conclusions: This study demonstrates that a low contact PA coaching intervention results in benecial changes in PA, anthropometrics and health-related outcomes in insuciently active adults presenting to an ambulatory care clinic. The signicant benecial changes were measured at post-intervention and the 9-month follow-up, demonstrating a maintenance effect of the intervention. Trial registration: Prospectively registered on the Australian and New Zealand Clinical Trials Registry (ANZCTR). registration

Research assessing the effects of telephone coaching for changes in PA has shown promise, however many studies are of short duration [9]. It is important to draw the distinction between initial behavior change and behavior change maintenance, which is harder to achieve [10]. While short-term behavior change has been demonstrated as a result of telephone coaching, studies that con rm long term behavior change are scarce [11,12]. The assessment of outcomes at least six-month post-intervention, where no contact with participants has been made since the intervention has ceased is required to provide a more robust measure of behavior change maintenance [13].
In a previous study (Healthy4U), we assessed the e cacy of telephone coaching for changes in PA in a selfselected sample of insu ciently active ambulatory hospital patients [14]. At 3-month post-intervention, participants in the intervention group demonstrated signi cant increases in PA and health-related outcomes compared to controls [14]. The present study builds upon the H4U study by extending follow-up measures to include a six-month post-intervention period to assess behavior change maintenance [13], decreasing the number of intervention sessions to reduce costs [15], and using referral by hospital surgeons as the recruitment strategy to simulate integration of the intervention as routine non-admitted hospital care.
The primary aim, therefore, was to examine the effectiveness of the PA telephone coaching intervention for change and maintenance of PA in insu ciently active patients referred by consulting hospital surgeons.
Secondary aims were to investigate the effectiveness of the telephone coaching for changes and maintenance in anthropometry, PA self-e cacy, and health related quality of life in this population.

Design
The study was a single-blind RCT ( Fig. 1) [16] that was registered prior to participant recruitment (ACTRN12619000036112).

Participants
Participants were recruited from an ambulatory, secondary care clinic in a major tertiary hospital in regional Victoria. Recruitment involved consulting orthopaedic and general surgeons providing, during the normal course of the consultation, a verbal recommendation to engage in PA coaching and a sequentially numbered research ier (Additional le 1) to adult patients who, in their view, would bene t from increased PA. Potential participants contacted the research team of their own volition using information on the yer. Sequential numbering allowed the research team to quantify both the number of individuals referred by surgeons and the number who subsequently acted on this referral.
Participants were included if they were between 18 and 69 years, and did not meet the recommended PA guidelines [17]. Exclusion criteria included: su ciently physically active; an existing medical condition that contraindicated PA (indicated by the Physical Activity Readiness Questionnaire); deaf/hearing impaired; disabling neurological disorder; severe mental illness such as psychosis; learning disability; dementia; registered blind; housebound or resident in nursing home; non-ambulant; pregnancy; and advanced cancer.

Procedure
Participants who were eligible and consented to take part were randomly allocated to either the intervention or the control group using a computer generated random number sequence (randomizer.org). Assignments were prepared and sealed in sequentially numbered opaque envelopes. Intervention assignment was made by opening the next envelope in the sequence, after: (1) the recruiter had determined eligibility for the study; (2) participants had consented to take part; (3) attendance at an education session was con rmed; and (4) baseline measurements were completed.

Intervention
All enrolled participants attended an education session prior to group allocation. The education session was a facilitated learning session based around PA self-management and was carried out using a self-determination theory (SDT) framework [18]. SDT is a motivational theory commonly used to illicit changes in PA [19]. SDT was used in this group setting to support, educate and motivate participants around PA changes [18].
The intervention group completed a telephone-based coaching intervention that comprised integrated motivational interviewing and cognitive behaviour therapy (MI-CBT). The coaching was delivered in ve by 20-min sessions over 12 weeks. The intervention schedule, theories and techniques are displayed in Table 1. The intervention was delivered using a motivational interviewing (MI) framework, with MI used as the underpinning approach to in uence motivation, ambivalence and self-e cacy to be physically active [20]. MI microskills (open-ended questions, a rmations, re ections and summaries) were utilised in all sessions [20]. The CBT coaching focused on six theory-derived determinants of PA: PA outcome expectations, PA outcome experiences, PA values, PA barrier self-e cacy, social support and relapse prevention [21]. The cognitive behaviour therapy (CBT) strategies were incorporated within a MI framework to support PA change and maintenance [22]. The intervention was delivered by an experienced allied health clinician trained in MI-CBT, including workshop attendances, and one-on-one coaching from an experienced practicing psychologist. The clinician previously delivered 145 hours of MI-CBT in the H4U study [14]. Pro ciency was assessed using the MI-CBT delity scale using audio-recorded sessions. Table 1 Physical activity coaching schedule, content, theory, determinants and behaviour change techniques.

Session
Week Session determinants Physical activity values.
• Exploration of current and historical physical activity behaviours; • Identify telephone coaching outcome expectations; • Identify physical activity outcome expectations; • Determine level of motivation for increasing physical activity (e.g. how motivated are you to increase physical activity on a scale of 1-10? Why did you give it a 3, as opposed to a 4 or 5?); • Identify and address unrealistic physical activity expectations; • Assess barriers to physical activity; • Discuss goals and action plans.
Cognitivebehavioural techniques: • Elicit PA outcome expectations and experiences; • Elicit values and physical activity priorities; • Identify physical activity barriers and problem solving; • Goal setting -behavioural; • Action planning.

Session
Week Session determinants • Review of goal progress from session 1; • Barrier identi cation and determine level of selfe cacy for overcoming barriers (e.g. how con dent are you to overcome barrier X on a scale of 1-10? Why did you give it a 3, as opposed to a 4 or 5?); • Progress and amend action-plan and goals; • If physical activity goals involve program based activities (e.g. strength training, walking groups) individual to source contact details.
Motivational interviewing strategies as above.
• Illicit and explore change talk.
Cognitivebehavioural techniques: • Problem solving; • Goal setting; • Focus on past success; • Prompt experiential learning through trial and error.

Session
Week Session determinants Content Techniques 3 4 Outcome expectations and experiences in relation to physical activity goal progress.
• Review of goals and progress from session 2; • Explore current experiences of physical activity; • Barrier identi cation and self-e cacy strategies for overcoming barriers; • Discuss self-monitoring strategies to monitor goal (e.g. physical activity tracking); • Discuss intervention timelines and action plan for the next two weeks.
Motivational interviewing strategies as above.
Cognitivebehavioural techniques: • Review of physical activity behaviour and outcome goal(s); • Elicit current physical activity outcome experiences; • Goal planning, and what-then plans; • Education regarding selfmonitoring of behaviour or outcomes; • Relapse prevention.

Session
Week Session determinants Content Techniques 4 6 Physical activity outcome expectations; Exercise selfe cacy; Coping strategies; Future planning.
• Review of progress from session 3; • Explore current experiences of physical activity; • Relapse prevention -tailored to individual needs; • Discuss intervention timelines and action plan for the next six weeks.
Motivational interviewing strategies as above.
Cognitivebehavioural techniques • Elicit current physical activity outcome experiences; • Coping strategies (e.g. physical activity pacing, planning); • Engaging social support; • Relapse prevention 5 12 Theory of behavioural maintenance; Relapse prevention; • Intervention recap; • Review of progress from previous session and intervention as a whole; • Identify what has helped PA changes; • Identify what can helped PA maintenance; • Relapse prevention -identi cation of potential future scenarios, and what-then plans for overcoming issues (e.g. if I experience X, then I will do Y); • Additional follow-on services -community health promotion services/exercise services.
Motivational interviewing strategies as outlined above.
Cognitivebehavioural techniques: • Action planningfocus on past and current success; • Problem solvingwhat-if planning.

Outcome Measures
Participants' characteristics and outcome measures were recorded at baseline, after 3 months of intervention (post-intervention) and at 9 months (follow-up) by assessors blinded to the study group assignment. The primary outcome, MVPA (minutes/day) was assessed using a tri-axial accelerometer (wGT3X-BT; Actigraph, USA).
Participants were instructed to wear the accelerometer on their hip at all times over 7 consecutive days, excluding sleep and water-based activities. PA was calculated using the manufacturers software (Actilife; Actigraph, USA) with cut points by Freedson Adult (1998) used to provide daily measures of MVPA (> 1951 cpm) [23].
Accelerometer wear time was based on activity counts per minute (CPM). Non-wear time was de ned as 60 minutes or more of consecutive activity counts of zero, with a spike tolerance of 2 min and 100 cpm. Participants used logbooks to report activities and periods of accelerometer non-wear. Non-wear time was compared to participants' notes on their logbook. Non-wear time was compared to participants' notes on their logbook. A minimum of 10 h per day was used as the cut-off for a valid day of measurement and a minimum of 5 days of data were required including at least 1 weekend day [24]. Weekly MVPA was computed based on the average of all valid days per person. A daily average of 21 min of MVPA over a 7 day period is su cient to meet the recommended PA guidelines [17].
Waist circumference was measured to the nearest 0.1 cm using a rigid anthropometric measuring tape (Lufkin, US). Body mass was recorded to the nearest 0.1 kg using a calibrated scale (model 813; Seca, Germany). Free standing stature was recorded to the nearest 0.1 cm using a calibrated equipment with the participant barefoot (Portable stadiometer; Seca, Germany). Body mass index (BMI) was calculated by dividing body mass by the square of height. Self-e cacy to be physically active was measured using a validated PA self-e cacy survey [25].
Health-related quality of life (HrQoL) was measured using the Medical Outcomes Study Short Form 12 Health Survey (SF-12) which is a reliable tool with published psychometric support [26].

Study size
Utilising data from the H4U study [14], a sample size of 50 participants per arm was calculated to be su cient to detect a between group difference of 30 min/week MVPA, with the alpha set at 0.05, and the power set at 0.80.
Protecting against a drop-out rate of 20% over the 9-month study duration, 60 participants were recruited and randomised into each arm. analyses were undertaken on data with outliers removed. Repeated sensitivity analyses provided no indication that the outliers had a signi cant effect on the outcome; therefore, all data were included in analyses. Intention-totreat analysis was used for missing data using the last observation carried forward approach [27]. Repeat sensitivity analyses were undertaken on data with and without imputing the last-observation-carried forward value and provided no indication that the imputed values had a signi cant effect on the outcome.

Results
Utilising the sequentially numbered study iers, we know that 2076 individuals were provided with the study information and a recommendation to engage with the PA coaching service. The H4U-2 study team were contacted by 682 individuals (33%), of which 120 consented and were eligible to participate in the study (Fig. 1).
Of the 305 individuals who chose not to participate, 282 did not want to enroll in the study but did want support to be more physically active; these individuals proceeded to enroll in the hospital's standard PA health promotion program. These data indicate that when ambulatory hospital patients are recommended by a surgeon to participate in a PA coaching intervention, 33% demonstrate su cient interest to enquire about the service, and almost 20% will take up a PA coaching intervention.
120 participants (68% female) completed baseline assessment and were subsequently randomised into the intervention or control groups. Baseline demographic and clinical characteristics between the intervention and control groups were similar (Table 1). Drop-out rates were low with 115 participants completing their 3-month assessment, and 108 participants completed their 9-month assessment (Fig. 1). Mean accelerometer wear time was 14 ± 3 hours per day and 6.1 ± 0.8 days per week (out of 7 days per week). Almost all participants (96%) enrolled into the intervention arm received their scheduled 5 sessions of PA telephone coaching. The typical length of each session was 18 ± 4 min.  The proportion of individuals undertaking su cient daily MVPA to meet the PA guidelines was similar across both groups at baseline, with 8% (n = 5) of the intervention group and 13% (n = 8) of the control group su ciently active.
In the control group this proportion decreased to 10% (n = 6) at 3 months, and decreased further to 3% (n = 2) at 9 months. In contrast, the proportion of individuals in the intervention group undertaking su cient daily MVPA increased to 55% (n = 33) at 3 months, and dropped slightly to 52% (n = 31) at 9-months.

Discussion
PA telephone coaching resulted in a signi cant increase in MVPA that was maintained at 9-months in adults attending ambulatory secondary care clinics. The intervention also resulted in signi cant improvements in body mass, waist circumference, BMI, PA self-e cacy, and HrQoL. The positive changes exhibited in outcomes at 3months and 9-months indicate short-term and maintenance effects of the intervention. The attrition rate of 10% was low. This study offers important information on the potential effects that can be achieved by a targeted, patient-centred PA lifestyle intervention delivered in an ambulatory hospital setting.
The intervention led to higher MVPA levels in the short and the long-term compared to the control group. The intervention group signi cantly increased MVPA at 3 months (post-intervention) and maintained this change at 9month follow-up. In contrast, the objectively assessed MVPA of the control group declined below baseline at 3 months, and declined further at follow-up. Very few studies have analysed the long-term effects of remotely delivered PA coaching [8,28]. The effect size observed in this study (0.20) was higher than that found (0.11) in a meta-analysis of remote PA interventions for self-reported PA change [29]. Additionally, self-reported PA following a PA coaching intervention was maintained after a no-contact follow-up, whereas objectively assessed PA decreased [30]. Objectively measured increases in MVPA in the intervention group that were maintained following a 6-month no-contact period indicate that change in behaviour was maintained at 9 months.
The majority of intervention participants were meeting the PA guidelines at 3 months and 9 months. This was in stark contrast to the control group where the proportion of su ciently active individuals decreased at 3 months and decreased further at 9 months. The increase in MVPA in the intervention group and the group differences between the control and the intervention group are highly relevant. Previous studies have documented that 15 minutes a day of MVPA can decrease chronic disease risk [3], attenuate the risk of sedentary behaviours [31], and reduce all-cause mortality [32]. Participants in the intervention group not only signi cantly increased MVPA from baseline to follow-up, but on average attained the recommended levels of PA. The observed effects of the intervention on MVPA can be considered sustainable given the objectively measured MVPA levels were maintained 6 months after the end of the intervention.
Compared to control, the intervention participants experienced improvements in their body mass, waist circumference and BMI from baseline to follow-up. These improvements were maintained during the no contact period from the end of coaching sessions for a further 6 months. At follow-up, the intervention groups demonstrated signi cant improvements in body mass (-2.1 kg), WC (-1.3 cm), and BMI (-0.8 kg/m2). The magnitude of long-term change in anthropometrics is comparable to changes reported in other studies using telephone coaching interventions, though none of these were conducted in the ambulatory hospital setting [33,34]. The positive changes in the intervention group and the group differences between the intervention and control group are relevant, and could have important population-health implications for addressing chronic disease risk factors. Even at modest levels, weight loss and decreases in waist circumference are bene cial for chronic disease risk reduction [35,36]. The recruitment into this study was based upon changing PA, not anthropometrics.
Additionally, intervention components only addressed issues relating to PA beliefs, attitudes and plans. The positive results for these secondary outcomes indicates that PA moderately, but signi cantly induces anthropometric changes, and it is important in the maintenance of these changes [37].
Baseline scores for PA self-e cacy indicated that both groups had low-to-moderate con dence in their ability to be physically active. In the control group PA self-e cacy decreased signi cantly over time. This contrasted with the trajectory of the intervention group, who increased PA self-e cacy at 3 months, and even further at 9 months. The changes in PA self-e cacy potentially mediated the changes in PA amongst the groups [38]. The intervention increased PA self-e cacy and PA, while the control group demonstrated simultaneous decreases in both these outcomes. The MI-CBT intervention demonstrated e cacy in improving psychological determinants in the short and long term, including self-e cacy to overcome exercise barriers and maintain change. Self-monitoring, goal setting, feedback on outcome of behavior and action planning are known to be effective for behaviour change, and can strengthen autonomy which is important for maintenance of change [39]. MI-CBT strategies can in uence the determinants associated with PA maintenance if implemented correctly, and appear to be particularly important for long-term effects [40].

Strengths and limitations
Using consulting surgeons to identify insu ciently physically active individuals was an important strength of this study. Once identi ed, surgeons discussed the need for PA change with insu ciently active patients and referred them to the study. This approach was based on surgeons' stated preferences, previously ascertained, for clear referral pathways into specialist behaviour change programs [41], and demonstrates how preventive health can be successfully embedded into routine ambulatory hospital care. The use of sequentially numbered study iers permitted the calculation of the PA intervention interest and uptake. It is encouraging in this respect that one-third of the individuals made contact with the study team after referral by a surgeon, and almost 20% went on to undertake PA coaching of some type.
The uptake of the intervention itself is also promising given the opt-in procedure that was used and the eligibility criteria that were applied. Many insu ciently active people are not ready to change important behaviours and are therefore unlikely to volunteer for a study such as this [42]. Nevertheless, the individuals who did enroll in the study still needed to make those changes and we were able to demonstrate effectiveness in this group due to the robust nature of the RCT study design. This strengthens con dence in the transferability and scalability of our ndings.
In the H4U study we demonstrated the e cacy of PA telephone coaching in self-selected sample of ambulatory care patients [14]; in this study we have demonstrated its effectiveness when used as the end point in a referral pathway starting with consultant surgeons working in ambulatory secondary care.
The participant retention rate in this study was high, with only 12 participants lost to follow-up. Intervention adherence rate was also high, with 96% of participants receiving all 5 sessions of telephone coaching. The use of objectively measured PA at all time points was a considerable strength of the study, offering precise estimates of PA intensity. For a regional hospital, delivering the PA intervention via telephone permitted extending the reach to both geographically and socially disadvantaged areas. A limitation of the study may be the involvement of only one hospital, though this permitted the continuation of a previous body of work towards integrating preventive health in that hospital. Additionally, the broad generalizability of these ndings might be di cult because the majority of participants were female and obese.

Conclusions
Ambulatory hospital appointments provide an important opportunity for initiating PA behaviour change. The H4U-  CONSORT ow diagram of the study.