Physical activity (PA) is important for a healthy cancer survivorship trajectory. Being physically active post diagnosis is vital to reducing the risks of cancer-specific and all-cause mortality and improving survival (1, 2). Cancer survivors are also susceptible to a range of treatment-related side effects including fatigue, pain, insomnia, neuropathy, and lymphoedema (3) that may adversely affect quality of life (QoL) (4). PA has been found to improve health-related QoL (HRQoL) and reduce anxiety, fatigue, pain, and sleep problems in cancer survivors (5). Despite increasing evidence that PA improves cancer outcomes, many survivors do not meet the recommendations (6) to participate in at least 150 min of moderate-intensity aerobic PA per week and resistance or strength training at least twice weekly (7).

There are also substantial geographic inequalities related to health and survival. Cancer survivors who reside in non-metropolitan areas are more likely to be insufficiently active and obese (8, 9) and have poorer cancer survival compared with their counterparts living in major cities (8, 10). There is also evidence that non-metropolitan cancer survivors have a poorer QoL compared with their metropolitan counterparts (11, 12). Furthermore, non-metropolitan cancer survivors face barriers to PA engagement such as the availability of and access to exercise programs, alongside their cost (13). Effective, distance-based PA interventions have the potential to reduce health inequalities for non-metropolitan cancer survivors by reducing barriers to exercise and facilitating PA participation.

Distance-based interventions have demonstrated improvements in health outcomes including HRQoL and cancer-related symptoms (14, 15). The review of mobile health (mHealth) interventions on QoL in cancer survivors by Buneviciene et al. (2021) (15) found a statistically significant improvement in global Health Status (mean difference of 7.05 in PA interventions), similar to the effects (weighed mean difference of 6.78) of a meta-analysis of PA interventions on HRQoL in breast cancer survivors (16). However, only one (17) out of four RCTs (17–20) demonstrated superiority of the mHealth-delivered PA intervention on HRQoL over the control group. Furthermore, none of these interventions used smart wearables in conjunction with health coaching or recruited only non-metropolitan cancer survivors. In addition, only one study (21) was based on CRC and recruited patients during treatment. A gap in the literature exists on the effectiveness of wearable activity technology interventions to promote PA and preserve or improve HRQoL in geographically underserved breast and CRC survivors following treatment.

The Promoting Physical Activity in Regional and Remote Cancer Survivors (PPARCS) trial explored the efficacy of a smart wearable device (the Fitbit Charge 2™), in conjunction with telephone-health coaching in an entirely distance-based intervention to increase moderate-to-vigorous PA (MVPA) in Australian breast and colorectal cancer survivors (22). The PPARCS intervention significantly increased MVPA with a between-group net difference in MVPA of 50 min/week favouring the intervention group (23), which was maintained at follow-up (24). The improvement or preservation of HRQoL is important in cancer survivorship and is often included as a secondary outcome measure in clinical trials (25).

The primary aim of this paper was to report the effects of the PPARCS trial on HRQoL in non-metropolitan breast and CRC survivors. Secondary aims were to explore within group changes across time.

The trial was a two-arm multicentre randomised controlled trial (RCT) conducted across five Australian states (New South Wales, Victoria, Western Australia, South Australia, and Tasmania) from March 2019 through to February 2021. The study was approved by the St. John of God Hospital Human Research Ethics Committee (Reference #1201) and registered (ACTRN12618001743257). Written informed consent was obtained from participants prior to enrolment. The protocol and trial design have been described previously (22). An overview of the methods is outlined below.

A total of 87 participants were randomised to intervention (n = 43) and control (n = 44) groups. Figure 1 displays the reach, enrolment, and allocation of participants, and Supplementary File 1 includes the Consolidated Standards of Reporting Trials (CONSORT) checklist for the reporting of the study (34). Demographic characteristics were similar across groups at baseline ( Table 1 ). There were 69 participants (79%) who remained in the trial at T3 (72.1% in the intervention group). Those who remained at T3 did not differ from those who did not by age, gender, baseline MVPA, cancer type, or months since diagnosis. The medians (IQR) in both arms across the duration of the study are presented in Table 2 for all scales comprising the EORTC QLQ-C30.

The remotely delivered PPARCS trial significantly increased MVPA in the intervention group (23), and the increase was maintained at follow-up (24). Specifically, the net change in MVPA at follow-up was 52.5 min/week (95% CI 11.0 to 94.0, p = 0.013), with the intervention group showing increased MVPA from T1 to T3 of 67.7 min/week vs. 15.2 min/week among controls (24). Despite these changes, the present analysis indicated that the intervention did not improve HRQoL. The lack of intervention effects may have been due to the relatively small sample size and the notable ceiling and floor effects, with many survivors reporting a relatively high QoL, mostly free of symptoms and with high functioning at baseline, therefore leaving little room for improvement. Nevertheless, there was a clinically meaningful improvement in global QoL in the intervention group at T2 (8.3 points (75 to 83.3)) and was maintained at 24 weeks. In comparison, the control did not improve their global QoL baseline score of 66.7. Despite no evidence of a statistical difference between the groups on global HRQoL, a clinically important change in HRQoL is considered achieved when the improved score matches the criteria for small effects (i.e., a change of 4–10 points), and this is evident for global HRQoL in the intervention group (16). In a meta-analysis of PA interventions in breast cancer, Aune et al. (2022) (16) also found that despite mostly small effect sizes, half of the results were nevertheless considered clinically significant.

There were no statistical between group effects on any of the function scales, although the median difference between groups for physical function was 6.7 points and could be considered a small effect (change of 5 to 15 points) and clinically meaningful (16). Physical function was maintained throughout the trial in the intervention group but decreased in the control group. The symptom scales had response patterns suggestive of significant floor effects. Pain was the only symptom with evidence of an arm by time interaction reflecting the higher pain scores in the control group when collapsed across time points, although pain increased in both groups between end of intervention and follow-up. Increased pain over time has been reported previously (18) and is difficult to explain unless the result of injury from increased PA or weather affecting chronic conditions such as arthritis. These findings are contrary to meta-analytic findings favouring exercise intervention compared with usual care for pain in cancer survivors (standardised mean difference: −0.45) (35).

In general, PA interventions in cancer survivors have resulted in higher global HRQoL and improved physical functioning (16, 36) with weaker effects for emotional and mental functioning (16). To date, there has been limited evidence for the use of mHealth PA interventions to improve HRQoL in cancer survivors. In the few RCTs that have examined the utility of wearable interventions to increase PA and improve HRQoL, most have found no differences in HRQoL between treatment groups (i.e., 37–39), other than for fatigue (measured through the FACIT) favouring the intervention group in a trial using a smart wearable (Garmin Vivofit2) in conjunction with five telephone-based behavioural counselling sessions over 12 weeks (40). There are likely to be several reasons for the ineffectiveness of PA mHealth interventions on HRQoL in cancer survivors, including small sample sizes that are insufficiently powered to detect change, less intensive or formal support, and exercise adherence. For example, Kraemer et al.’s (2022) (41) meta-analysis found no significant effect on QoL for home-based interventions. However, sensitivity analyses found that where intervention adherence was ≥80%, home-based or supervised PA interventions were effective in improving the QoL in CRC patients. The present analysis is one of the first to examine the effects of an entirely distance-based smart wearable intervention, in conjunction with health coaching, on HRQoL in non-metropolitan breast and CRC survivors. We found that PPARCS preserved global health status, with evidence of clinically meaningful improvements in global HRQoL, which is an important outcome.

Although the PPARCS trial produced a significant increase in MVPA that was maintained at follow-up, the present analysis indicates the intervention did not improve HRQoL. However, findings should be interpreted with caution given the sample size and the high scores for HRQoL observed at baseline limiting room for meaningful change.