Energy System Assessment in Survivors of Breast Cancer

Abstract

Background Survivors of breast cancer commonly report functional limitations, including cancer-related fatigue (CRF) and decreased aerobic capacity. One key gap is addressing the 3 energy systems (aerobic, anaerobic lactic, and alactic), requiring assessment to establish a baseline exercise intensity and duration. Objective This study examined the feasibility of energy system–based assessment, also providing descriptive values for assessment performance in this population. Design This was a cross-sectional study. Methods Seventy-two posttreatment survivors of breast cancer were recruited. Following a baseline musculoskeletal assessment, women attempted 3 energy system assessments: submaximal aerobic (multistage treadmill), anaerobic alactic (30-second sit-to-stand [30-STS]), and anaerobic lactic (adapted burpees). Heart rate (HR) and rating of perceived exertion (RPE) were recorded. Secondary outcomes included body composition, CRF, and upper- and lower-limb functionality. Results Seventy of 72 participants performed the 30-STS and 30 completed the adapted burpees task. HR and RPE specific to each task were correlated, reflecting increased intensity. Women reported low-moderate levels of CRF scores (3% [2.1]) and moderate-high functionality levels (upper-limb: 65.8% [23.3]; lower-limb: 63.7% [34.7]). Limitations All survivors of breast cancer had relatively low levels of CRF and moderate functioning. Additionally, on average, participants were classified as “overweight” based on BMI. Conclusion This study is the first to our knowledge to demonstrate feasibility of energy system assessment in survivors of breast cancer. Using a combination of HR and RPE, as well as baseline assessment of each energy system, clinicians may improve ability to prescribe personalized exercise and give patients greater ability to self-monitor intensity and progress.

Energy System Assessment in Metastatic Breast Cancer: A Cross-Sectional Study

“…Both objective and subjective data were collected during these assessments to provide physiological and perceived capacity. A summary is provided below on this outcome, with further details provided in a recent publication by Cuesta-Vargas and colleagues [19]. For all energy system assessments, resting heart rate (HR) was determined and then monitored during each task with a pulsometer Polar M400 with a Thoracic band H7 HR (POLAR Spain) [21] for both safety and participant response monitoring.…”

“…This cross-sectional study evaluated each of the three primary energy systems, guided by previous research in non-metastatic breast cancer survivors [19] and adapted to consider additional factors and challenges associated with metastatic breast cancer such as metastasis location and enhanced neuropathy issues. Assessments were completed at University Clinical Hospital, Málaga, Spain.…”

“…They then completed symptom-limited energy system testing, which comprised of up to three different tasks to evaluate aerobic, anaerobic alactic and anaerobic lactic systems, following these safety considerations: Two minutes of adapted burpees (anaerobic lactic assessment): Participants were eligible if they were able to perform ≥15 repetitions in the 30-STS with an RPE ≤ Additionally, women who had presented any kind of symptoms or lower-limb issues during the 30-STS were deemed ineligible to undertake this assessment. While overall assessment protocols followed those outlined by Cuesta-Vargas et al [19], adaptations were made to assessment progression based on the additional potential symptoms associated with metastatic breast cancer. For example, due to factors such as location of metastases and impacted structures (e.g.…”

“…As highlighted in previous research [19], limited information of exercise intensity guidelines is often compounded by physical assessments in those with breast cancer focusing on cardiovascular/aerobic pathway exercise intensities. While both submaximal and maximal exercise testing may be used, these do not provide information on anaerobic energy system capacity and therefore limited intensity guidance [20].…”

“…As such, more repeatable, transferable tests are required to provide exercise capacity assessment across all three energy systems. While this has been examined in breast cancer survivors [19], there is a need to expand this research to women with metastatic breast cancer. Given the three energy systems play an imperative role in performance of daily activities, enabling individuals to undertake both short, high-intensity activity as well as lower-intensity, sustained activity, it is understandable these various systems should be addressed in assessment.…”