Feasibility of a Supervised Virtual Exercise Program for Women on Hormone Therapy for Breast Cancer : Translational Journal of the American College of Sports Medicine

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Feasibility/Pilot Study Report

Feasibility of a Supervised Virtual Exercise Program for Women on Hormone Therapy for Breast Cancer

Myers, Samantha A.1,2; Weller, Sarah3; Schwartz, Sarah4; Van Patten, Cheri3; LeVasseur, Nathalie3; Faulkner, Guy5; Campbell, Kristin L.1,2,4

Author Information
Translational Journal of the ACSM: Fall 2022 - Volume 7 - Issue 4 - e000213
doi: 10.1249/TJX.0000000000000213
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Adjuvant endocrine therapy significantly improves survival in women with hormone receptor–positive breast cancer and is typically administered for a period of 5 yr or longer (1–3). The three main classifications of endocrine therapy administered to individuals with breast cancer are selective estrogen receptor modulators (e.g., Tamoxifen), aromatase inhibitors (AI) (e.g., Letrozole), and ovarian function suppressors (e.g., Lupron) in combination with Tamoxifen or AI. Adverse treatment side effects are common and can include vasomotor symptoms, arthralgias, weight gain, and bone loss, which negatively affect quality of life (QoL) (4,5). Despite the demonstrated efficacy of adjuvant endocrine therapies, approximately 50% of women do not adhere to their prescribed regimens; 20% will discontinue their AI medication in the first year and identify menopausal symptoms and arthralgias (i.e., joint pain or stiffness) as the key reasons for poor adherence or cessation of treatment (6–8).

Regular aerobic and resistance exercise is one potential strategy to decrease the side effects of endocrine therapies and may lead to improved medication adherence (9–12). Most women with a prior breast cancer diagnosis are insufficiently active, with approximately 11% meeting exercise oncology guidelines, which recommend achieving 150 min of moderate- to vigorous-intensity physical activity (PA) and two resistance training (RT) sessions each week (13,14). Studies show that supervised exercise is one of the most effective ways to improve exercise behaviors of women with prior breast cancer diagnosis (15–17).

Given the high prevalence of breast cancer worldwide, exploring interventions that improve QoL and medication adherence of those taking long-term endocrine therapy for breast cancer treatment is warranted. This program was originally designed to test the feasibility of an in-person, group-based supervised exercise program for women receiving endocrine therapy for breast cancer; however, in response to local health mandates during the coronavirus disease 2019 (COVID-19) pandemic, the format transitioned to virtual delivery. The purpose of this study was 1) to explore the feasibility of delivering a virtual supervised exercise intervention for women with a prior breast cancer diagnosis receiving endocrine therapy and 2) to examine the preliminary efficacy of the intervention on physical function (PF).


This is a prospective single-arm pilot study of a virtual supervised strength and aerobic exercise program for women with a prior breast cancer diagnosis receiving endocrine therapy called Breast Cancer Endocrine Therapy Fitness (BE-FIT). The study was initially designed to be an in-person, group-based exercise program and was stopped after 2 wk in March 2020 due to COVID-19 pandemic restrictions. The intervention was adapted to be delivered virtually.

This study was approved by the University of British Columbia Research Ethics Board (H19-02250) and was conducted in compliance with the Tri-Council Policy Statement: Ethical Conduct for Research Involving Humans, TCPS 2 (2014), and Good Clinical Practice (GCP).


Participants were initially recruited through the British Columbia Cancer Breast Oncology Unit and the After Breast Cancer Clinic by oncologists, nurse practitioners through a certified exercise physiologist (CEP) embedded in the Breast Oncology Unit, and self-referral. Individuals were eligible if they met the following criteria: female; 19 yr or older; diagnosis of stages I–III breast cancer treated with curative intent; completed primary treatment including surgery, radiation therapy, and/or chemotherapy; currently receiving adjuvant endocrine therapy (Tamoxifen, AI, ovarian function suppressor) for at least 3 months; within 3 yr of starting endocrine therapy (and had at least 1 yr of therapy remaining); able to read and speak English; and willing to attend a twice-weekly exercise program for the duration of the study. After the study transitioned to virtual delivery, to be eligible individuals also needed access to a tablet, smartphone, laptop, or computer with a built-in video camera and to be willing to appear on camera for the duration of an exercise session to allow for safety monitoring. Previous participants were contacted by telephone or e-mail to notify them of the BE-FIT virtual delivery option. If interested, the participants completed an additional eligibility screening, updated study consent form, and virtual baseline assessment conducted by a CEP. Finally, a preexercise screening questionnaire was completed by a CEP to establish the participant’s physical and medical readiness to participate in exercise using the Get Active Questionnaire, which identifies comorbidities that may preclude participation. If the participant reported new-onset (within 6 months) or uncontrolled conditions, the CEP contacted the physician for approval to the program.

Exercise Intervention

The BE-FIT program was a 6-wk group-based exercise program composed of 12 supervised, group-based, 60-min exercise sessions delivered twice weekly. All sessions were delivered virtually via live two-way video using a video-conferencing system (i.e., Zoom). The format and the exercise prescription were not adapted for the virtual sessions. Each session included an aerobic warm-up (e.g., marching, punching, jumping jacks) at a progressive light- to moderate-intensity (rating of perceived exertion (RPE) = 5–7 out of 10), full-body (RT) exercises (e.g., bodyweight squat, banded chest press, banded reverse fly) with a set of three TheraBands™ (Hygienic Corporation, Akron, OH) (4–10 lb) that were provided to participants by mail. The exercise prescription was progressive, targeting moderate intensity (1–3 sets of 8–15 reps with RPE 6–8 out of 10) and range of motion exercises targeting upper body flexibility, followed by a full-body static stretching cooldown. Individualized exercise modifications and progressions were provided as required to accommodate an individual’s needs. The most common modifications included a seated single-leg leg press for those with knee pain or using a chair for balance during other unilateral lower limb exercises.

The education component included instruction on self-regulatory behavior skills to assist in the long-term adoption of positive exercise behavior using the multiprocess action control framework (17,18). Regulatory strategies are a significant predictor of action control (18). The multiprocess action control framework aids the translation of a formulated intention to PA behavior; over time, individuals move toward reflexive processes of habit, which lead to PA maintenance (18).

Each week, the instructor introduced the topic during the group warm-up, followed by a facilitated group discussion during the cooldown. The topics included 1) benefits of exercise for endocrine therapy symptoms, 2) self-monitoring, 3) goal-setting, 4) overcoming barriers, 5) exercise at home and community resources, and 6) reflection. One adaptation for the virtual format to encourage the development of group dynamics and social support was an optional “social session” to allow participants to connect after the exercise session. The exercise instructor muted, stopped their video, and left their device to allow the participants to connect on their own.

In addition to the supervised virtual RT sessions, a home aerobic exercise (AE) program was part of the 6-wk intervention, namely, progressing from 1 to 3 d·wk−1 of AE, with each home-based session lasting 30–60 min. Participants were instructed to independently engage in the weekly AE goals and record their activities in their exercise log to send to the instructor. Participants were encouraged to continue exercising in a self-directed manner after the completion of the program.

Primary Outcome

The primary outcome was the feasibility of delivering the BE-FIT program virtually. Feasibility was evaluated based on a priori targets set based on the expert opinion of the research team of what would support future research on exercise programming for this cancer group. The targets were specific to program recruitment (>30% recruitment ratio), transition to virtual delivery (>75%), attendance (>70% virtual session attendance), attrition (<30% dropout), and fidelity of group belongingness (average score ≥15 on belongingness questionnaire (19)) at the end of the program. If a feasibility component target was not met, it would be adapted based on learnings from the study. Recruitment was defined as the number of participants who enrolled in the in-person study compared with the number of participants referred for the original BE-FIT in-person program. The transition to virtual delivery was defined as the number of participants who enrolled in the virtual study compared with those who originally enrolled in the BE-FIT program. Furthermore, the fidelity of group belongingness was selected to assess social connectedness in a virtual format commonly observed during in-person trials for women with a breast cancer history (20).

Secondary Outcomes

Patient-reported outcomes were collected by self-reported questionnaires administered online at baseline and the end of the intervention. Endocrine therapy symptom scores were assessed by the Functional Assessment of Cancer Therapy–Endocrine Subscale (FACT-ES) (21), and medication adherence was assessed by the Voils Domains of Subjective Extent of Nonadherence self-reported medication nonadherence measure (22). Exercise behaviors were collected as total weekly moderate- to vigorous-intensity PA levels, and RT frequency was calculated using the modified Godin Leisure-Time Exercise Questionnaire (23). QoL was assessed by the RAND Short-Form 36-item test (24).

Adaptation to physical measurements transitioned from in-person to a synchronous virtual assessment by the CEP to assess PF, using a 30-s chair stand test (25), and balance, using the tandem balance test from the Short Physical Performance Battery (26). Written instructions for waist and hip circumference (cm) measurements were provided before the assessment and performed by the participant per the CEP’s verbal instructions. Participants self-reported height (cm), weight (kg), and resting heart rate (bpm). Body mass index was calculated from height and weight (kg·m−2). If an adverse event occurred during the exercise sessions, the CEP would document and report to the principal investigator.

Because of limitations in staffing, a purposive sample of participants were invited to complete an individual program satisfaction telephone interview 3 to 6 wk postintervention. The sampling strategy aimed to include a wide range of responses reflecting age, employment status, marital status, and program attendance. The interview guide was designed to help inform subsequent group-based exercise interventions delivered virtually. The questions covered aspects the participant enjoyed, disliked, and would change about the program. The interviews were conducted by an individual who was not involved in the delivery of the exercise program.

Data Analysis

Descriptive statistics were calculated for continuous variables presented as mean and SD, and frequencies and percentages were reported for categorical variables. Change of pre- and postintervention (6 wk) continuous variables were measured using paired t-tests, dichotomous variables were analyzed with a McNemar test, and Wilcoxon signed rank tests were used for ordinal variables. Effect size was calculated for each test, using Cohen’s d (small, 0.2; moderate, 0.5; and large, 0.8) for paired t-tests, phi coefficient (φ) (small effect, 0.1; moderate effect, 0.3; and large effect, 0.5) for McNemar tests, and Rosenthal coefficient (r) (small effect, <0.30; moderate effect, 0.30 < 0.50; and large effect, ≥0.50) for Wilcoxon signed rank tests. The sample size was not calculated for this pragmatic study and was drawn from the literature, which suggests that 24 to 30 participants are optimal to evaluate feasibility (27–30). The level of significance (α) was set at 0.05. All analyses were conducted using SPSS statistics version 28 (IBM, Armonk, NY).


Participant characteristics are listed in Table 1. The average age was 55 yr, with a range from 35 to 70 yr. Most were not working, with approximately 30% retired and 26% on sick leave/long-term disability. Aerobic exercise guidelines (150 min·wk−1 of moderate intensity) were met by 33% of participants and approximately 42% met RT guidelines (2 d·wk−1). Over half of the participants were married, and most women had postsecondary education (96.3%). On average, women had received endocrine therapy for 9 months and were 17.5 months out from surgery (n = 26), 11.5 months since radiation (n = 24), and 15 months since chemotherapy (n = 17).

TABLE 1 - Patient Characteristics for All Patients Grouped by Endocrine Therapy Type.
Characteristic All Tamoxifen AI P
Age (yr) 55.5 ± 10.2 52.4 ± 8.9 58.4 ± 10.8 0.13
 35–49 8 (29.6) 5 3 0.48
 50–59 9 (33.3) 5 4 0.74
 60–69 8 (29.6) 2 6 0.16
 70+ 2 (7.4) 1 1 1.00
Highest education
 Master’s or higher 3 (11.1) 2 1 0.56
 Bachelor’s degree 16 (59.3) 6 10 0.37
 Some college 6 (22.2) 5 1 0.10
 High school graduate 2 (7.4) 0 2 NA
Employment status
 Working full time 4 (14.8) 2 2 1.00
 Working part time 3 (11.1) 1 2 0.56
 Self-employed 3 (11.1) 2 1 0.56
 Unemployed 2 (7.4) 2 0 NA
 Sick leave/long-term disability 7 (25.9) 3 4 0.71
 Retired 8 (29.6) 3 5 0.48
Marital status
 Married or common law 18 (66.7) 9 9 1.00
 Single 4 (14.8) 2 2 1.00
 Separated or divorced 4 (14.8) 2 2 1.00
 Widowed 1 (3.7) 0 1 NA
Endocrine therapy
 Months receiving endocrine therapy 9.0 ± 8.2 7.0 ± 9.0 9.0 ± 7.8 0.67
 Receiving Tamoxifen 13 (48.1) Reference Reference Reference
 Receiving AI 14 (51.9) 13 14 1.00
Breast cancer treatments
 Months since surgery (n = 26) 17.5 ± 61.2 18.5 ± 89.7 17.5 ± 6.2 0.29
 Months since radiation therapy (n = 24) 11.5 ± 24.5 12.0 ± 35.8 11.0 ± 5.8 0.32
 Months since chemotherapy (n = 17) 15.0 ± 74.6 16.0 ± 116.5 123.5 ± 7.0 0.27
Exercise levels
 MVPA (min·wk−1) 85.0 ± 125.8 80.0 ± 122.2 90.0 ± 132.8 0.65
  Strenuous 0 ± 28.8 0 ± 36.4 0 ± 22.0 0.74
  Moderate 60.0 ± 124.2 60.0 ± 122.0 80.0 ± 100.9 0.59
  Mild 130.0 ± 100.5 120.0 ± 104.6 150.0 ± 100.9 0.78
  Achieves 150 min·wk−1 (n = 24) 8 (33.3) 3 (12.5) 5 (20.8) 0.56
 RT (sessions per week) 1.0 ± 1.2 1.0 ± 0.9 2.0 ± 1.5 0.25
  Achieves 2 sessions per week (n = 24) 10 (41.7) 3 (12.5) 7 (29.2) 0.19
Values are shown as mean ± SD for continuous and categorical variables and frequency (%) for dichotomous variables.
MVPA, moderate- to vigorous-intensity physical activity; NA, not applicable.

Primary Outcomes

The BE-FIT virtual program met all a priori feasibility targets (Table 2). Of the 79 individuals referred to the BE-FIT in-person program, 31 were eligible and enrolled with a recruitment rate of 39% (exceeding the 30% recruitment ratio target). Transition to the virtual BE-FIT program was 87% (27 out of 31), exceeding the 75% target. The remaining feasibility outcomes were assessed for participants of the virtual program (n = 27). For attendance, 261 out of 288 RT sessions (91%) were attended, with a median attendance of 11.0 ± 1.2 sessions per person (range = 7–12 sessions) and exceeded the target of >70% of attended RT sessions. Missed sessions were due to vacation/travel (n = 8), unknown cause (n = 7), injury outside of study (n = 4), and other reasons. Three individuals dropped out of the intervention with an 11% attrition rate, meeting the <30% dropout target. Reasons for dropout were due to injury unrelated to the program (n = 1), an inability to commit to the time required to attend sessions (n = 1), and preexisting musculoskeletal issues that caused pain during the program (n = 1) (Fig. 1). The average score for group belongingness was 19.5 out of 20 and exceeded the average score target of >15) (Table 2).

TABLE 2 - Feasibility Items, Change in Physical Measures, and Patient-Reported Outcomes Pre- to Postprogram.
Feasibility Item A Priori Target Result Feasibility Achieved
Recruitment >30% 39% Yes
Transition to virtual >75% 87% Yes
Attendance >70% 91% Yes
Attrition <30% 11% Yes
Group belongingness >70% 98% Yes
Physical Measure (n = 24) Pretest Posttest Change P Effect Size
Resting heart rate (bpm) 67.4 ± 11.8 (40–96) 70.3 ± 11.0 (50–96) 2.9 ± 15.6 0.36 0.19 a
Body weight (kg) 65.3 ± 13.0 (43.5–103.4) 65.0 ± 12.6 (44.0–101.2) −0.3 ± 1.2 0.82 −0.05 a
Body mass index 24.6 ± 5.3 (18.0–39.1) 24.5 ± 5.1 (18.2–38.9) −0.1 ± 0.5 0.77 −0.05 a
Waist circumference (cm) 90.6 ± 10.6 (73.3–119.5) 88.3 ± 11.9 (67.0–120.5) −2.3 ± 3.8 0.005* −0.63 a
Hip circumference (cm) 101.1 ± 10.3 (80.8–127.5) 100.3 ± 10.4 (81.5–127.0) −0.8 ± 1.7 0.01* −0.54 a
30s CST (reps) 20.7 ± 6.6 (13–40) 23.7 ± 7.5 (15–48) 3.0 ± 2.5 b <0.001* 1.22 a
Balance (level 3) (s) 10 ± 0 (10) 10 ± 0 (10) 0 ± 0 1.0 0.0 a
Exercise Behavior ( n = 24) Pretest Posttest Change P Effect Size
Strenuous (min·wk−1) 17.9 ± 32.5 (0–120) 39.5 ± 45.5 (0–200) 21.6 ± 42.2 0.007 c, * 0.47 a
Moderate (min·wk−1) 103.5 ± 124.2 (0–450) 145.2 ± 169.0 (0–720) 41.7 ± 170.7 0.27 c 0.24 a
Mild (min·wk−1) 145.6 ± 104.2 (0–420) 117.1 ± 98.7 (0–420) −31.5 ± 117.3 0.21 c −0.23 a
MVPA (min·wk−1) 121.4 ± 125.8 (0–450) 184.7 ± 195.5 (0–920) 63.3 ± 194.9 0.12 c 0.3 a
RT (sessions per week) 1.3 ± 1.2 (0–5) 2.2 ± 1.7 (0–8) 0.9 ± 1.7 0.01 c, * 0.51 a
150-min MVPA per week 8 (33.3%) 11 (45.8%) 2 (8.3%) 0.25 d 0.77 e
2+ RT sessions per week 10 (41.7%) 19 (79.2%) 9 (37.5%) 0.004 d, * 0.43 e
SF-36 Item ( n = 23) Pretest Posttest Change P Effect Size
PF 80.7 ± 20.9 (10–100) 83.3 ± 15.6 (40–100) 2.6 (19.6) 0.67 c 0.09 f
RL physical health 40.6 ± 42.2 (0–100) 55.4 ± 44.5 (0–100) 14.8 (40.4) b 0.19 c 0.16 f
RL emotional problems 65.3 ± 42.2 (0–100) 76.8 ± 36.8 (0–100) 11.5 (37.4) b 0.11 c 0.34 f
Energy/fatigue 40.8 ± 23.5 (5–85) 52.6 ± 25.3 (0–95) 11.8 (12.6) b <0.001 c, * 0.72 f
Emotional WB 60.8 ± 18.6 (24–96) 75.7 ± 18.6 (24–100) 14.9 (13.0) b 0.001 c, * 0.68 f
SF-36 Item ( n = 23) Pretest Posttest Change P Effect Size
Social functioning 77.2 ± 18.7 (38–100) 82.1 ± 23.3 (13–100) 4.9 (16.9) 0.25 c 0.24 f
Pain 52.8 ± 20.4 (33–90) 68.3 ± 21.9 (23–100) 15.5 (24.1) b 0.02 c, * 0.49 f
General health 65.2 ± 16.2 (25–90) 66.5 ± 20.6 (25–95) 1.3 (11.1) 0.65 c 0.10 f
FACT-ES Subscale ( n = 24) Pretest Posttest Change P Effect Size
FACT-G total (0–108) 80.2 ± 17.2 (35–103) 87.5 ± 14.3 (50–108) 7.3 (6.1) b 0.003 c, * 0.69 f
FACT-ES total (0–184) 132.0 ± 19.9 (92–164) 137.6 ± 20.3 (83–167) 5.6 (10.3) b 0.08 c 0.36 f
FACT-ES-23 total (0–200) 127.0 ± 22.0 (82–161) 134.9 ± 20.7 (77–166) 7.9 (11.4) b 0.06 c 0.38 f
ESS-19 (0–76) 57.3 ± 7.8 (44–69) 56.2 ± 6.2 (34–64) −1.1 (4.8) 0.37 c 0.18 f
ESS-23 (0–92) 67.8 ± 8.8 (50–83) 67.5 ± 8.1 (39–79) −0.3 (6.5) 0.84 c 0.04 f
Physical WB (0–28) 19.7 ± 3.9 (12–25) 21.4 ± 4.9 (11–28) 1.7 (3.2) 0.02 c, * 0.49 f
Social/family WB (0–28) 20.2 ± 5.4 (7–28) 21.5 ± 5.1 (20–30) 1.3 (3.2) 0.36 c 0.19 f
Emotional WB (0–24) 17.5 ± 4.9 (3–24) 18.8 ± 4.9 (1–23) 1.3 (2.4) 0.05 c, * 0.40 f
Functional WB (0–28) 17.4 ± 6.4 (1–26) 19.7 ± 4.9 (7–28) 2.3 (4.8) 0.05 c, * 0.40 f
DOSE-nonadherence ( n = 24) Pretest Posttest Change P Effect Size
Total number who missed, skipped, or did not take medicine over the past 7 d 6 (25%) 2 (8%) −4 (17%) 0.13 d 0.52 e
Values are shown as mean ± SD (range) for continuous and categorical variables and frequency (%) for dichotomous variables. Paired t-tests were used, unless described.
* Statistical significance (P < 0.05).
a Effect size is shown as Cohen’s d for paired t-tests.
b Minimal clinically important differences: resting heart rate >3 bpm, weight >2.5 kg, body mass index >1.1 kg·m−2, waist circumference >2.5 cm, hip circumference >2.5 cm, 30-s chair stand test (30s CST) >2.6 reps, SF-36 ~5–10 for each measure; FACT-G >4, FACT-ES >4, subscales >4.
c Wilcoxon signed rank test.
d McNemar test.
e Effect size is shown as phi coefficient for dichotomous variables.
f Effect size is shown as Rosenthal coefficient for categorical variables.
DOSE-nonadherence, Voils Domains of Subjective Extent of Nonadherence; MVPA, moderate- to vigorous-intensity physical activity; RL, role limitations; SF-36, RAND Short-Form 36-item survey; WB, well-being; 30s CST, 30-s chair stand test.

Figure 1:
CONSORT (Consolidated Standards of Reporting Trials) diagram.

Secondary Outcomes

Preliminary efficacy of the intervention was examined in participants who completed the intervention (n = 24). Improvements in PF, as measured by the 30-s chair stand test, were statistically significant (change = 3.0 ± 2.5 repetitions; P < 0.001, d = 1.22) and met the Minimal Clinically Important Difference score of >2.6 reps (25). No statistically significant changes in balance were found. Statistically significant changes were also demonstrated for waist circumference (P = 0.005, d = −0.63) and hip circumference (P = 0.01, d = −0.54), whereas there was no statistically significant change in body weight or body mass index (Table 2). There was a significant improvement in self-reported strenuous exercise levels (change = 21.6 ± 42.2 min·wk−1; P = 0.007, d = 0.47) and the number of RT sessions per week (change = 0.9 ± 1.7 sessions; P = 0.01, d = 0.51) (Table 2), whereas the number of individuals meeting the current aerobic PA guidelines for health (i.e., at least 150 min·wk−1 of aerobic activity) did not increase significantly. Clinically meaningful changes were found in five of eight subscales of health-related QoL (RAND Short-Form 36-item test) (Table 2), and statistically significant changes were seen in the following subscales: energy/fatigue (change = 11.8 ± 12.6 (0–95); P < 0.001, r = 0.72), emotional well-being (change = 14.9 ± 13 (24–100); P = 0.001, r = 0.68), and pain (change = 15.5 ± 24.1 (23–100); P = 0.01, r = 0.49) pre- to postprogram. Statistically significant changes for self-reported endocrine therapy symptoms (FACT-ES) were demonstrated in physical well-being (change = 1.7 ± 3.2; P = 0.02, r = 0.49), emotional well-being (change = 1.3 ± 2.4; P = 0.05, r = 0.40), functional well-being (change = 2.3 ± 4.8; P = 0.05, r = 0.40), and the FACT-G total score (change = 7.3 ± 6.1; P = 0.003, r = 0.69) (Table 2). Although not statistically significant, there was a trend toward a clinically meaningful improvement on patient-reported medication adherence with a mean change of 17% (P = 0.13, φ = 0.52) (Table 2). There were no adverse events reported during the program.

Of the 11 participants invited to the qualitative interview, 9 responded and participated. All participants reported no difficulties or issues with technology. Although some participants reported that the program length was manageable because it was easy to commit to, others reported the desire for a longer program duration (weeks). Overall, participants noted that the social connection in the virtual intervention was less compared with previous experience from in-person group-based exercise programs; however, this was not viewed as unfavorable or a barrier to using a virtual format. Participants also recommended that developing cohorts of participants of similar ages and comparable life stages might help with social connectedness. Many participants reported that the provided Therabands were foreign, and additional education about the use of the equipment before the start of the program may have been valuable.


Our findings provide some of the first reports on the feasibility of supervised, virtual, synchronous, group-based delivery of an exercise program to people with prior breast cancer diagnosis. Overall, our pilot demonstrated that a virtual delivery approach is feasible to deliver to women receiving endocrine therapy treatment and has the potential to significantly improve PF, exercise behavior, and QoL. These findings suggest that virtual delivery of a group-based exercise program is feasible and should be considered when designing exercise oncology programs as it may increase the reach of exercise oncology services and reduce participation barriers (31).

Attendance to the 12 synchronous virtual exercise sessions (91%) was higher than typically reported by supervised, in-person exercise oncology interventions (32). Two previous randomized trials of supervised in-person exercise programs for women receiving endocrine therapy for breast cancer have reported lower attendance rates during a 6-month program (72%) (33) or a 12-month program (70%–72%) (9). These preliminary data are consistent with recent findings from the Winters-Stone et al. (34) ongoing randomized control trial of supervised exercise in women with prior diagnosis of breast cancer. The trial pivoted from in-person to virtual supervised RT due to COVID-19 restrictions; mean attendance to the “live online” virtual exercise was 86% compared with 81% for the in-person exercise classes (34). Attrition to the BE-FIT intervention was low at only 11% and is comparable with the low attrition rate reported by Winters-Stone et al. (34), with 95% retention for those engaged in the “live online” classes compared with only 80% for those who attended the in-person classes. Prior studies delivering in-person supervised exercise interventions for women with a previous breast cancer diagnosis receiving endocrine therapy have reported attrition rates from 6% to 24% for in-person supervised programs (4,28–30) and from 8% to 15% for unsupervised exercise programs (35,36). Reasons for higher attendance and lower attrition to virtual programs may be attributable to reducing barriers to accessibility, such as location and time, which are often reported as barriers with in-person exercise interventions (9,37). Indeed, our findings for high attendance and low attrition to a virtual delivery option could be attributed to two factors. First, the program was shorter in duration (6 wk), and second, the program coincided with public health stay-at-home restrictions during the COVID-19 pandemic, which reduced social and professional commitments. Whether higher attendance and lower attrition with virtually delivered programs will be maintained after the lifting of restrictions associated with the COVID-19 pandemic, which disrupted usual work and social commitments by participants, will need to be assessed. Insights from the satisfaction interviews included recommendations for increasing the duration of the program in future iterations and incorporating supportive material for appropriate use of the Therabands before the first session. However, these initial findings suggest that virtual exercise delivery may indeed be a strategy to increase reach, feasibility, and accessibility of specialized exercise oncology programming led by specially trained exercise professionals.

Supervised in-person exercise has consistently demonstrated greater efficacy than home-based or unsupervised exercise (38). A meta-analysis of 34 randomized controlled trials (RCT) evaluating home-based or supervised exercise programs for cancer survivors showed that supervised exercise affected QoL and PF that was twice as large compared with unsupervised exercise programs (38). Virtual delivery with supervision may be a way to observe the same benefits in PF and self-reported outcomes as in-person supervised programs. Our 6-wk BE-FIT program resulted in similar improvements in PF and QoL to those of previous in-person supervised programs (38). The guidance of a CEP may elicit these larger effects; however, the key components of in-person supervised exercise delivered in a group setting that will need to be replicated virtually are social support and camaraderie, which are more challenging to deliver in a virtual group-based exercise setting (39). The high group belongingness reported in the BE-FIT program suggests that this format is successful in providing social support, and the satisfaction interviews provided insight into future strategies, such as increasing the duration of socialization before class to increase social connectedness, which should be considered in future trials.

Relevant to the field of exercise oncology, our pilot study demonstrated a clinically meaningful 17% increase in medication adherence to endocrine therapy for people with hormone receptor–positive breast cancer. High adherence to endocrine therapy is associated with improved prognosis and survival (9); despite its efficacy, many discontinue their prescribed regimen because of adverse side effects, including arthralgias and myalgias (40). A 2020 meta-analysis of eight RCT by Lu et al. (40) reported a significant effect of exercise on the management of arthralgias from endocrine therapy and reported significant improvements in pain, stiffness, and QoL. To date, only one RCT has examined the effect of exercise on medication adherence with a 1-yr in-person RT and AE program in 121 women with prior breast cancer diagnosis receiving endocrine therapy (9). A nonsignificant higher adherence rate of 4% was observed in the intervention at 12 months compared with the control group (9). These findings, along with the preliminary efficacy demonstrated in our pilot study, show a potential effect of combined RT and AE to improve endocrine therapy treatment tolerance. This outcome may be of key interest to oncology care teams and highlights the potential value gained from incorporating exercise oncology within the clinical breast oncology units.

Strengths of the present study include a novel focus on examining the feasibility of delivering a supervised, synchronous resistance and aerobic exercise program virtually to address the challenges to in-person supervised exercise during the COVID-19 pandemic. The virtual format was safe and has the potential to increase our reach to those living in rural and remote geographic areas. Although concerns around technological access in some geographical areas or communities, as well as computer literacy among older adults, are valid, a shift to virtual, supervised programming provides the opportunity to recruit a more heterogeneous sample than previous in-person programs, improving generalizability and potentially having a greater public health effect. However, this study was a single-arm pilot initially designed to be conducted in person within metropolitan Vancouver, BC. Hence, the sample does not represent regions outside of urban areas, and the sample size was not powered for preliminary efficacy of outcomes reported. Therefore, they should be interpreted with caution. In addition, it is important to note that the home-based component aimed to increase AE levels to meet current PA guidelines for health. Although there was no statistically significant change in the number of participants meeting these guidelines postprogram (46%), significant increases in strenuous minutes of AE per week may have also influenced positive patient-reported outcomes and physical measures. The measurement of adherence to components of the exercise prescription among both modalities should be explored using technology to objectively assess if strong associations between exercise type and outcomes exist. Furthermore, a ceiling effect was observed from the Short Physical Performance Battery balance test. If balance is a key focus, another test is needed.

Future research directions should include testing virtual delivery of the BE-FIT intervention in an appropriately powered RCT to test the effect on biopsychosocial outcomes for women with prior breast cancer diagnosis receiving endocrine therapy, as well as the feasibility of virtual exercise beyond the unique time of the COVID-19 pandemic. We now have such a trial underway (NCT04824339). More research is also needed to examine how key aspects of in-person supervised exercise programming can be translated successfully to a virtual format, namely, cultivating social support and provision of an individualized, progressive overload exercise dose.

In response to public policy and safety recommendations, the COVID-19 pandemic forced oncological health care services to transition from in person to remote based as appropriate. The transition to virtual delivery provides new ways to expand the reach of clinical programming outside of research institutions, which was previously limited. The BE-FIT pilot established feasibility and preliminary efficacy of delivering supervised exercise virtually to women with prior breast cancer diagnosis receiving endocrine therapy. Virtual delivery of supervised exercise programs for those with prior cancer diagnosis may be an alternative approach that improves accessibility and reach, providing a greater public health effect.

The authors acknowledge financial support from the BC Cancer Foundation. The authors declare no conflicts of interest. The results of this study do not constitute endorsement by the American College of Sports Medicine.


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