Barriers to and facilitators of improving physical activity and nutrition behaviors during chemotherapy for breast cancer: a sequential mixed methods study

Abstract

Purpose: Use qualitative and quantitative methods to explore factors influencing the adoption of guideline-based physical activity (PA) and dietary recommendations among participants enrolled in a lifestyle intervention during and after chemotherapy for breast cancer.

Methods: Among women with stage I-III breast cancer who participated in the intervention arm of the Lifestyle, Exercise, and Nutrition early after diagnosis (LEANer) trial, we used stratified, purposeful sampling to interview women who met both, one, or neither intervention goal after the 1-year intervention: (1) 150 min/week moderate-to-vigorous intensity exercise via a self-reported PA questionnaire and (2) improved self-reported diet quality measured by the Healthy Eating Index-2015. Semi-structured interviews were audio-recorded, transcribed verbatim, and analyzed using thematic content analysis.

Results: The 29 women interviewed were 52 ± 11 years old on average, with a mean body mass index of 29.6 ± 7.7 kg/m². Three themes emerged regarding aspects of the LEANer intervention that facilitated behavior change: (1) providing a conduit of trustworthy, timely, and personalized support and education; (2) shifting mindsets and enhanced understanding of the benefits of PA and nutrition during chemotherapy; and (3) fostering a sense of control and alternative focus. Factors described as hindering adoption of goals included: (1) adverse effects of chemotherapy and (2) competing priorities.

Conclusions: Women reported the external support, tailored education, and experiencing the physical and mental benefits of the LEANer intervention facilitated the adoption of the interventions' behavioral goals. Addressing chemotherapy-related symptoms and competing priorities may facilitate adherence to lifestyle interventions during chemotherapy for breast cancer.

Keywords: Breast cancer; Chemotherapy; Diet quality; Exercise; Lifestyle intervention; Mixed methods; Physical activity.