Enhancing Exercise Adherence Among Patients With Lateral Hip Pain

Background and Rationale: Greater Trochanteric Pain Syndrome (GTPS) is a commonmusculoskeletal condition affecting the lateral hip, with an estimated prevalence of10‐25% in the general population and a disproportionately higher incidence amongmiddle‐aged women. The condition is characterised by pain and tenderness localised to thegreater trochanter, most commonly attributed to gluteal tendinopathy (particularly of thegluteus medius and minimus tendons) and trochanteric bursitis. GTPS can significantlyimpair functional capacity, quality of life, and participation in daily activities.Current evidence supports therapeutic exercise, including progressive hip‐strengtheningprogrammes, as a first‐line treatment for GTPS. Despite this, the clinical effectivenessof exercise‐based rehabilitation is substantially undermined by poor patient adherence toprescribed programmes. Non‐adherence is a persistent and well‐documented challenge acrossmusculoskeletal rehabilitation settings, contributing to suboptimal outcomes, prolongedsymptom duration, and increased healthcare utilisation. Scalable, low‐resource strategiesto support adherence in this population are lacking.Theoretical Framework: The ASAP (As Soon As Possible) intervention is grounded inestablished behavioural science theory on motivational resource depletion andself‐regulatory capacity throughout the day. Research in ego depletion and time‐of‐dayeffects on self‐control suggests that motivational resources and executive function arerelatively stronger in the early waking hours and decline progressively as cognitive anddecisional demands accumulate throughout the day. Consequently, health‐related behavioursthat require deliberate effort or involve discomfort, such as adherence to a therapeuticexercise programme, are more vulnerable to avoidance or abandonment when deferred tolater in the day.The ASAP intervention operationalises this framework by encouraging participants tocomplete their prescribed exercises as early as possible each day, ideally immediately orshortly after waking. The rationale is that performing exercises during a window ofhigher motivational resources reduces the likelihood that competing demands will displacethe exercise behaviour. This approach is designed to be pragmatic, requiring nospecialised equipment, additional clinical contact, or complex behaviour changetechniques beyond the provision of psychoeducational information and, in one arm,periodic digital reinforcement.Study Design: This is a three‐arm, parallel‐group feasibility randomised controlled trial(RCT) with an embedded qualitative component. Participants are allocated in a 1:1:1 ratioto one of three groups using computer‐generated block randomisation (block size of six)administered via Sealed Envelope, an established online randomisation platform. Thethree‐arm structure enables simultaneous evaluation of (1) the ASAP timing conceptrelative to usual care, and (2) the incremental value of digital reminders as anadherence‐support adjunct.All participants are recruited through the Sport and Exercise Medicine clinic atUniversity Hospitals of Leicester NHS Trust and receive the same hip‐strengtheningexercise programme prescribed by their NHS healthcare provider as part of standardclinical care. The exercise programme itself is not an experimental variable; theintervention under investigation concerns exclusively the timing guidance and remindercomponents layered onto standard care.Intervention Arms:Group A ‐ ASAP with Reminders: Participants receive a written information leafletexplaining the theoretical basis for early‐morning exercise completion and itsanticipated benefit for adherence. In addition, participants receive weekly digitalreminders (delivered via a messaging platform) throughout the 28‐day primary interventionperiod. These reminders reinforce the ASAP timing message and prompt participants toprioritise morning exercise completion.Group B ‐ ASAP without Reminders: Participants receive the same information leaflet asGroup A but do not receive any digital reminders. This arm isolates the effect of thewritten psychoeducational component from the reminder‐augmented condition.Group C ‐ Usual Care Control: Participants proceed with their prescribed hip exerciseprogramme without receiving any additional timing guidance, written information relatingto exercise timing, or digital reminders. This arm reflects current standard practice andserves as the comparator condition.Feasibility Objectives: As a feasibility trial, the primary aim is to evaluate thepracticability and preparatory requirements for a future definitive full‐scale RCT.Specific feasibility criteria include:Recruitment rate: The rate at which eligible participants are identified, approached, andsuccessfully enrolled over the recruitment period.Retention rate: The proportion of enrolled participants who complete follow‐upassessments at each pre‐specified time point, including the primary endpoint at Day 28.Questionnaire completion rate: The proportion of completed data fields across all outcomemeasure timepoints, including the daily adherence survey.Participant acceptability: Qualitative and quantitative assessment of participants'experiences of the intervention, study procedures, and perceived burden.These parameters will inform sample size calculations, outcome selection, and proceduralrefinements for the design of a future definitive trial.Data Collection and Assessment Schedule: All data collection is conducted online via asecure digital platform. Participants complete a standardised battery of validatedoutcome measures at five timepoints: baseline (Day 1), Day 14, Day 28, Day 42, and Day84. This schedule is designed to capture short‐term adherence behaviour and earlysymptomatic response (Day 14 and Day 28), medium‐term outcomes following the activeintervention period (Day 42), and longer‐term maintenance of effect (Day 84).In addition, participants complete a brief daily adherence survey for the first 28 daysof the intervention period. This survey is estimated to take 1‐2 minutes per day andcaptures self‐reported exercise timing and completion, as well as any relevant contextualfactors affecting adherence on that day.Qualitative Component: Following completion of the quantitative phase, a purposivelysampled subset of participants across all three arms will be invited to participate inonline focus group discussions. These discussions will be conducted using asemi‐structured topic guide and will explore participants' subjective experiences of theintervention, perceived barriers and facilitators to morning exercise timing, theacceptability of the study procedures and digital components, and suggestions forintervention refinement. Focus groups will be audio‐recorded, transcribed verbatim, andanalysed using an appropriate qualitative framework methodology. Qualitative findingswill be integrated with quantitative feasibility data to provide a comprehensive basisfor informing a future definitive trial.Clinical Setting: Initial participant identification and recruitment takes place at theSport and Exercise Medicine clinic at University Hospitals of Leicester NHS Trust.Following enrolment, the study is conducted entirely online, enabling participation fromany location with internet access and supporting engagement from participants who mayhave mobility limitations or scheduling constraints associated with their GTPS diagnosis.