The impetus for the current review stems primarily from the growing need to close the research-practice gap that has long existed in the field of exercise oncology. Even with the overwhelming evidence on the feasibility, safety, and clinical benefits of exercise in cancer patients, exercise-based rehabilitation is still generally considered an adjunct instead of an integral component of care during treatment. The result of this evidence-practice gap is that most patients do not have access to exercise services while receiving cancer treatment, a period when the debilitating effects of cancer treatments are at their peak and can best be mitigated or ameliorated with exercise-based rehabilitation [8, 14, 33]. Despite a limited number of studies, implementing exercise services in [proximity to] a cancer unit appears to be an effective approach for increasing access to exercise-based rehabilitation for individuals on active treatment [27,28,29,30,31,32]. While this approach seems to be feasible for both the clinicians (the referring clinicians and those delivering the programs) and patients, the current evidence is not a confirmation of the overall feasibility of exercise service integration in oncology care settings. The lack of a clear implementation plan was evident across the included studies [27,28,29,30,31,32]. As critical to a successful service implementation as this may be, issues relating to funding and organizational buy-in hold even far greater implications for effective service integration and long-term sustainability.
Overall, service implementation was modest even though fidelity to any pre-implementation plan was not demonstrated. As a direct consequence of this downside, capacity for patient screening and risk stratification, effective patient triage, and structured referral mechanisms were generally lacking. Exercise services were largely operated independently of the clinical settings in which they were embedded, and staff leading these programs were also not part of patient core management team [29, 32]. This compromised the potential for shared decision-making in most programs and enabled communication gaps between the clinical staff and exercise service providers [29, 32]. Lack of an implementation plan was implicated in the poor coordination between exercise sessions and treatment time. In one study, patients reported that they could not attend exercise sessions because they constantly clashed with their treatment times . As co-location does not automatically translate to successful service integration, a detailed implementation plan ensures that structures and strategies that reflect the changing dynamics of the clinical environment housing an exercise service unit are put in place to drive effective and sustainable integration.
Access to exercise programs was relatively feasible and similar across the included studies. Most programs were open to participants two to three times a week [27, 29, 31, 32]. In one study, for example, exercise services were available from Monday to Thursday during the six months evaluation period . In another study, patients on admission had daily access to exercise programs throughout their inpatient stay . Another consistent finding across the included studies was the simplified and convenient nature of the referral process [27, 29, 31, 32]. Although well-defined referral pathways were generally lacking, patient referrals were simple and convenient. Exercise referrals were mostly verbal, directly from the referring clinicians (the oncologists, nurses, and other allied health staff) to the exercise programs [27, 29, 32]. One study reported an additional use of a central access point (email referral) to facilitate patient referrals further . Another major facilitator of referrals was patient feedback [27, 28, 32]. One study reported that doctors who received positive feedback directly from their patients were more inclined to refer more patients to the exercise program . By encouraging patients to feedback to their clinicians on their thoughts, experiences, and concerns with the exercise program, exercise service providers can motivate doctors [and nurses] to engage more fully and proactively with the referral process. Barriers to patient referrals were recorded at both individual and health service levels. At the individual level, while most doctors were aware of exercise benefits, particularly during cancer treatment, many lacked the will to refer patients to exercise programs. In one study, doctors reported referring patients to the exercise program only when they remembered and had the time to do so . At the health service level, low organizational buy-in, even with the reported evidence of adequate service promotion, was a major finding [27, 29, 31, 32].
Lack of organizational buy-in may be responsible for the overall low service penetration and utilization among the clinicians. For example, two studies reported overall service reach ranging between 10% and 12% [27, 29], with Kennedy et al.  reporting an annual reach of 10% to 14% over a 50-month evaluation period. One study identified only 31 exercise service programs in the whole of 6 out of 8 states/territories in Australia . Successful integration of exercise services in routine oncology care demands a concerted effort to develop and identify the right implementation strategies to provoke a cultural shift in the host organization, which is critical for increasing organizational buy-in. One way to achieve this is by providing education to the healthcare providers working in oncology settings. Healthcare providers can only refer patients to exercise service programs if they know how, when, and where patients can be referred for such services . To refer patients for exercise services, doctors and nurses, for example, should understand and appreciate the rehabilitation dimensions of their patient care and effectively and proactively screen patients for exercise interventions [8, 33]. As this is a relatively new frontier in cancer care, many healthcare providers in oncology settings may need to be trained on how to use exercise screening algorithms and referral guidelines to adopt these tools [8, 33]. Tools such as electronic medical records and integrated/central referral systems can improve service ease and efficiency, and ultimately utilization [8, 33].
Organizational buy-in can also be improved by enhancing the visibility of the service units. In one study, the referring clinicians were pleased with the value created by the frequent presence of physiotherapists in the cancer unit as they actively featured in ward rounds, offered clinical insights even during informal discussions, and took part in patient assessment and decision making . Another strategy to increase service utilization is to increase staff confidence, particularly in the safety of the exercise programs . This can be achieved by ensuring that the physiotherapists and other exercise specialists working in these settings have the right skills and training to match the peculiarities and dynamics of cancer care. Specifically, exercise prescriptions must be based on well-established international guidelines and recommendations while reflecting patients’ circumstances, needs, preferences, and values . Good communication, knowledge sharing, patient responsiveness, and teamwork can foster strong relationships between staff leading exercise programs and oncology clinicians and ultimately enhance service utilization . Regular service promotion within the clinical setting is another strategy to increase organizational buy-in. One study achieved this by providing regular updates and timely reminders through staff presentations, use of newsletters, and by introducing an alerting system in electronic medical records [27, 28, 31, 32]. Staff rotations and turnover reflect the dynamics of typical cancer care clinics. Regular awareness programs are thus critical to ensure that new staff is aware of the existence of these services.
Acceptance rate was relatively low across the included studies. One study, for example, found that only 64 patients took part in the exercise program out of 237 referrals received over 50 months . Another study reported almost 50% rejection rate among eligible patients referred to the exercise programs . In one study, some programs recorded even as low as 10% annual enrolment . Service compliance was also low among those that participated in the exercise programs except for one study that recorded as high as 71% compliance over a three-year evaluation period . The widely reported seemingly poor referral process may explain the low acceptance rate across the included studies. While the referral process was found to be simple and convenient for the clinicians, it may have lacked some critical elements that guaranty an effective referral mechanism, one of which is patient engagement. Illustratively, common reasons for non-utilization, missed sessions, and dropouts across the included studies were lack of interest , unwell due to treatment , COVID-19 restrictions , hospital readmission , disease progression , lack of awareness of service availability , and worsening symptoms including adverse skeletal events . These experiences appear to be underlined by a general lack of exercise self-efficacy and behavioral control which is a common observation in patients on active cancer treatment [34, 35]. The poor understanding of the complex nature of cancer disease and the appropriate exercise dose with minimal adverse effects required to derive health benefits are also potential accentuating factors among these patients [34, 35]. The referral process offers the treating oncologists and nurses a unique opportunity to support their patients in building confidence in their capabilities to initiate and maintain optimal exercise behavior. Oversimplifying the referral process robs the referring clinicians of opportunities to engage proactively with and counsel patients prior to their exercise journey. The observed low service uptake further speaks to the peculiar challenges of patients on active cancer treatment, especially those on hospital admission. These individuals constantly battle with multiple treatment-related complications and are generally unwell. Offering regular counseling and psychosocial supports and adapting exercise programs to reflect individual capacities, needs, and preferences can be another useful approach to increase uptake. Even though most patients were satisfied and willing to refer others to these programs, low service uptake and high dropout rates can be improved especially in the outpatient population by addressing sources of dissatisfaction, including early morning sessions, scheduling conflicts (i.e., by enabling a more flexible programs), absence of continuation plans (i.e., by considering, perhaps, more transformative exercise programs), and parking issues (i.e., by eliminating or subsidizing parking fees) [27, 29, 32].
Issues relating to funding also pose a major threat to sustainable service integration. Even though exercise services can be delivered with less sophisticated equipment, funds are required to cover routine operational costs, including daily consumables, staff salaries, maintenances, and in some locations, rents. Most of the programs were funded through grants and private donations [27, 29, 31, 32]. These sources are largely volatile and unsustainable. In one study, the average cost to the health service per patient was AUD $1, 104 with staff salaries being the primary expense . Most of the programs could not be sustained after the evaluation period, largely due to inadequate resources. For example, one study reported that two programs were closed because of lack of funds . In another study, authors reported that the exercise program was restructured at the end of the evaluation period to ensure that available funds are used to cover basic operational costs . Funding is a key driver of long-term service and should form primary consideration during the program planning phase. As health systems continue to grapple with limited resource allocation globally, funding challenges are even more pronounced in exercise oncology, given the pervasive misconception about rehabilitation as largely an adjunctive service. Governments, corporate sponsors, and insurance agencies are potential opportunities that could be explored for multiple funding streams . More research is therefore required to confirm the greater merits of integrative exercise-cancer care models to the broader health systems. This can provoke a cultural shift in healthcare funding policies to guaranty sustainable funding for exercise-based rehabilitation.
The strength of this review is evident in our reliance on multiple implementation outcome frameworks. By drawing extensively on well-established frameworks, our findings and recommendations offer critical information to support evidence-based practice, decision making, and future research. One major limitation of the current review is the limited number of studies available for inclusion, hence the inability to weigh fully without overstating the extent to which the differences across treatment settings may have influenced service implementation and how implementation may change in other cultures/settings. Further, as per the aim of our review, we did not evaluate the potential for this approach to translate into measurable clinical benefits. By excluding non-English articles, we may have further missed out on studies that could strengthen our findings and recommendations. Oncology care models that foster integrative exercise-cancer care units are recent and largely at the evaluation stage. While this may explain the paucity of literature, we caution that the current evidence only informs decision-making and evidence-based practice in light of these limitations and individual local settings.