Breast cancer survivors’ exercise program preferences can change during an exercise intervention and may be associated with exercise behavior change from pre- to post-intervention. This is the first randomized intervention study to our knowledge to elucidate program preference changes for the intervention vs. control condition coupled with exploring the associations between these preferences and post-intervention MVPA. Statistically significant changes over the 3-month intervention period were noted among the BEAT Cancer intervention recipients for five preferences (i.e., delivery, group/alone, supervision, location, type), while only two of the thirteen program preferences (i.e., counseling source and supervision) demonstrated a statistically significant change among those in the UC group. Two baseline preferences (i.e., group/alone and location) were associated with the BEAT Cancer intervention success from M0 to M3 and from M0 to M6 in the BEAT Cancer intervention group. Yet, location was the only preference associated with change in physical activity during the 3-month post-intervention period (M3-M6).
After receiving the BEAT intervention, the proportion of participants interested in face-to-face exercise counseling declined; however, it was still the most preferred mode of delivery. Similarly, the proportion preferring supervised exercise training decreased when assessed immediately post-intervention. Although the same change was seen within the UC group, analyses indicated a greater proportion of BEAT Cancer participants changed their preference from supervised to unsupervised training when compared with UC. These results indicate survivors had less of a desire for professional exercise support following the BEAT Cancer intervention. This could be a result of the intervention design tapering the exercise sessions from supervised in a facility to unsupervised home-based sessions over the 3-month period with the goal of helping participants become more independent with their physical activity behaviors. It seems possible that this design gave the participants the education needed to feel more capable of exercising on their own without needing more professional support.
Also, fewer survivors were interested in exercising at a facility after participating in the intervention, which was expected as the intervention transitioned from facility to home-based exercise sessions over the intervention period. While home-based exercise gained interest, having this preference at M3 was associated with a decrease in self-reported MVPA following the intervention from M3 to M6. Yet, free-living accelerometer-measured MVPA levels did not decrease among those who preferred to exercise at home. A possible explanation for these results may be that without traveling to a designated exercise location, the participants may feel like they are not being as active, thus self-reporting lower activity levels. Further research is needed to better understand if behavior changes preferences or vice versa and how these relationships may differ for free-living vs. volitional leisure-time physical activity behavior. Survivors who preferred exercise training in a group setting at M0 exhibited greater increase in self-reported MVPA between M0 and M6; however, at M3 the majority changed to preferring exercise training alone. As seen in this study and previous studies, having social support by training with a partner or in a group setting can provide accountability and increase activity levels [22–24]; yet, coordinating exercise in a group setting may be more difficult and require more effort than exercising alone, which could have contributed to this preference change. Since the intervention tapered to individual exercises sessions at home the participants may have gained confidence in exercising on their own. The majority of participants preferred a combination of both aerobic and resistance exercise training before and after the BEAT cancer intervention, yet after the intervention a portion of participants changed to no longer preferring the combination of both, enough to be statistically significant. Furthermore, when asked about specific types of exercise, resistance exercise training was least preferred by the majority of participants who reported to prefer another form of exercise (i.e., walking, water activities, cycling, yoga, etc.) over resistance training. Since the BEAT Cancer intervention focused on aerobic exercise training, specifically walking, participants may have been more inclined to focus strictly on aerobic rather than resistance exercise.
These results are consistent with those reported by Owens et al. [25] examining exercise program preferences in adults with metabolic syndrome. Participants’ preferences changed significantly from preferring supervised exercise training in a group setting to favoring independent (i.e., alone), unsupervised training following a 16-week, community-based lifestyle intervention. Our study and Owens et al. demonstrated a shift in program preferences from having a desire for professional supervised training and social support to wanting unsupervised, independent training sessions. Intervention fatigue was suggested as an explanation for the decreased interest in support, which could be a factor within any population, including breast cancer survivors. Alternatively, it was previously reported by our group that the BEAT Cancer intervention significantly improved self-efficacy within this sample [26], thus participants may have gained more confidence in exercising after the intervention and required less support.
Contrasting results were found in women with metastatic breast cancer following a 6-month unsupervised home-based intervention. Most participants favored training at home but following the unsupervised home-based intervention, the majority changed to preferring training at a community-based facility. Further, patients with head and neck cancer had a significant increase in preference towards training at a cancer center following a 12-week, group resistance exercise training intervention. While the findings are not consistent with our results, this preference change could support intervention fatigue, as the observed preference changes were a shift away from the intervention design. It seems possible that these contrasting results could be due to people preferring variety and influence the desire for the opposite of the intervention.
No statistically significant differences were found for counseling source preference in this study; however, previous studies in the cancer patient populations found a statistically significant change [11, 15]. The majority of head and neck patients changed from preferring a personal trainer to a professional with a kinesiology degree [11], while the majority of metastatic breast cancer patients preferred an exercise specialist with an increase in this preference following their intervention [15]. While both studies can offer potential explanations for the observed results, it is important to note that metastatic breast and head and neck cancer patients have greater risks for side effects or adverse events and cancer/treatment-related sequelae, which may influence the differences in results.
The strengths of this study include the randomized controlled trial design, large sample size (relative to the current literature), high participant retention rate, and assessment of both objective and self-report physical activity within the context of statistically significant intervention efficacy at M3 and M6 [7, 11, 15, 25]. This study adds value to the current limited literature reporting pre/post changes in program preferences during an exercise intervention in cancer survivors. Further, no prior study to our knowledge within the cancer population has compared program preference changes in an intervention vs. control group, in an effort to account for natural evolution of preferences that may occur over time in the absence of an intervention [25].
Study Limitations
We acknowledge this study is limited in variability among race and rurality of the sample. Participants were primarily White women residing in metro or small urban areas and may have better access to exercise resources than non-White breast cancer survivors in more rural or inner-city urban areas. Additionally, these findings may not be generalizable to other cancer types beyond breast or to resistance training interventions. Further, our findings should not be used to conclude the prevalence of exercise preferences because it was not a population-based survey. Nevertheless, comparison of our study with a similar survey conducted in a large population-based sample of breast cancer survivors [14], demonstrates similar findings in that both report the majority of breast cancer survivors preferring face-to-face exercise counseling, flexible exercise scheduling, walking as the exercise type, and exercising alone, unsupervised, and at home/no preference [14].
Clinical Implications
Our study suggests that tailoring to social support (i.e., group vs. individual) and location (i.e., home-based vs. facility) preferences may be the key for increasing perceived acceptability of and engagement with an intervention. Further, preference may change over time suggesting periodic reassessment for additional tailoring may be indicated. Future study is warranted to determine why preferences change and whether tailoring an intervention towards preferences is feasible and optimizes exercise behavior change short and long term. Current approaches in the exercise oncology field acknowledge that a generic exercise program does not work for the general population and interventions are commonly tailored using the Frequency, Intensity, Time, Type (FITT) principles and no other intervention characteristics. Previous research has highlighted that tailoring interventions solely using the FITT principles may not be enough to optimize adherence to a physical activity intervention within the breast cancer population [27]. It is important to note the results in the present study demonstrate that breast cancer survivors have specific exercise program preferences and could benefit from interventions that are tailored using preferences along with the FITT principles.