22–23 Jul 2026
Heidelberg Congress Center
Europe/Berlin timezone

Preliminary Patterns of Adherence to Remote Exercise During Neoadjuvant Chemotherapy: Insights from the NeoACT Trial

23 Jul 2026, 14:00
45m
Heidelberg Congress Center ( Heidelberg Congress Center )

Heidelberg Congress Center

Heidelberg Congress Center

Czernyring 20 69115 Heidelberg Germany
1 - Scientific Poster Poster Session

Speaker

Lea Stark (Department of Medical Epidemiology and Biostatistics, Karolinska Institutet, Stockholm, Sweden)

Description

Background:
The Neo-ACT trial is an ongoing, pragmatic RCT evaluating whether structured, home-based exercise during neoadjuvant chemotherapy can improve treatment efficacy in patients with breast cancer. The enrolment target is 712 evaluable participants; as of December 2025, 339 participants have been randomized. The intervention consists of 120 minutes of weekly exercise combining resistance and high-intensity interval training delivered via the Vitala mobile app, alongside encouragement to achieve an additional 150 minutes of moderate physical activity. In real-world settings, insufficient adherence remains a major challenge.

Objective:
To present preliminary data on exercise adherence and its association with exercise self-efficacy during neoadjuvant chemotherapy.

Methods:
Exercise activity was monitored using the Vitala app. A valid exercise session was defined as lasting ≥20 minutes. Adherence was defined as achieving ≥65% of the prescribed exercise dose between randomization and pre-surgery testing. Exercise self-efficacy was assessed at pre-surgery testing using the 9-item Self-Efficacy for Exercise (SEE) scale, measuring confidence to exercise under common barriers. Physiotherapists monitored app activity and contacted patients with low adherence.

Results (Preliminary):
Among 104 participants assigned to and completing the intervention by November 2025, 97 completed the SEE questionnaire. Fifty participants (48%) met the predefined adherence criterion. Adherent participants reported significantly higher exercise self-efficacy than non-adherent participants, both for the total SEE score (Wilcoxon rank-sum test, p = 5.5 × 10⁻⁶) and across all individual barrier items (all p < 0.05). For example, self-efficacy to exercise when feeling stressed was higher among adherent participants (median 8 [IQR 2]) than among non-adherent participants (median 5 [IQR 7], p < 0.001).

Conclusion:
Higher exercise self-efficacy was strongly associated with better exercise adherence, highlighting the importance of behavioural and motivational factors. Preliminary findings suggest that patient heterogeneity and treatment-related side effects may limit adherence to app-based exercise interventions.

Keywords

breast cancer; neoadjuvant chemotherapy; remote exercise; adherence

Abstract submitters declaration yes
Conflict of Interest & Ethical Approval yes

Author

Lea Stark (Department of Medical Epidemiology and Biostatistics, Karolinska Institutet, Stockholm, Sweden)

Co-authors

Martina Rossland (Department of Neurobiology, Care Science and Society, Division of Nursing, Karolinska Institutet, Stockholm, Sweden) Renske Altena (Medical Unit Breast, Endocrine Tumours and Sarcoma, Theme Cancer, Karolinska University Hospital, Department of Oncology Pathology, Karolinska Institutet, Stockholm, Sweden) Linda Swedin (Department of Medical Epidemiology and Biostatistics, Karolinska Institutet, Stockholm, Sweden) Elena Leinert (Department of Gynecology and Obstetrics, University of Ulm, Ulm, Germany) Peeter Karihtala (Helsinki University Hospital, Comprehensive Cancer Center, Finland) Thorsten Kuehn (Chairman of EUBREAST, University of Ulm and Die Filderklinik, Germany) Yvonne Wengström (Department of Neurobiology, Care Science and Society, Division of Nursing, Karolinska Institutet, Stockholm, Sweden) Jana de Boniface (Department of Medical Epidemiology and Biostatistics, Karolinska Institutet/ Department of Surgery, Capio S:t Göran’s Hospital, Stockholm, Sweden Stockholm, Sweden)

Presentation materials

There are no materials yet.