Aims: Over the past two decades, the volume of high-quality evidence supporting exercise as being beneficial to cancer survivors has grown exponentially; however, the potential harms of exercise remain under-studied. Consequently, the trade-off between desirable versus undesirable outcomes of engaging in exercise remains unclear to clinicians and survivors. Practical guidance on the collection and reporting of harms in exercise oncology is lacking and the direct application of existing guidelines from other settings (e.g., pharmacological) is inappropriate. We present the harms reporting protocol developed by the ihop research group and refined through exercise-oncology trials since 2015.

Methods: The ihop exercise-oncology harms protocol was guided by national and international guidelines for harms reporting in clinical trials involving therapeutic goods or medical devices, and modified to ensure applicability to exercise. The protocol has been refined through an iterative process of implementation and adjustment through use in multiple exercise-oncology trials involving varied cancer types (breast, brain, gynaecological) and stages (I–IV; primary/recurrent diagnoses), and heterogeneous exercise intervention characteristics (face-to-face/telehealth delivery; supervised/unsupervised exercise).

Results: The ihop harms protocol involves: Step 1 – Monitor occurrence of adverse events (AEs) through systematic (i.e., standardised checklists or tests) and non-systematic (i.e., ‘have you experienced any undesirable events?’) surveillance; Step 2 and 3 – Assess and Record AEs, including type (e.g., injury, treatment-related side-effect), causality (relationship of AE with exercise), severity (grade1–5), and impact on intervention participation; Step 4 – Review of causality by harms panel (and revision as necessary); and Step 5 – Analyse and Report, including frequencies and details of all-cause and exercise-related AEs.

Conclusions: Future research should refine standardised exercise-specific nomenclature, and validate methods of assessing causality. Nonetheless, the ihop harms reporting protocol provides a foundation from which to improve the quality of harms assessment and reporting immediately, while concurrently providing a framework for future refinement.