Background: High-intensity interval exercise (HIIE) has many benefits for females living beyond cancer, yet the vigorous intensity may deter individuals from performing HIIE compared to traditional moderate-intensity continuous exercise (MICE). The purpose of this study was to examine enjoyment, self-efficacy, and intentions for HIIE compared to MICE in females living beyond cancer.
Methods: Participants performed HIIE and MICE in a randomized, counterbalanced order. HIIE consisted of 10, 60-second intervals at 125% of participants' ventilatory threshold (VT), with 60-second rest intervals. MICE included 20 minutes of cycling at 90% of the VT. Enjoyment, self-efficacy, and intentions were self-reported after each activity. Higher scores indicated better attitudes. Paired t-tests were interpreted using Cohen's d.
Results: Participants (N=13; Mage=49.2±11.3 years) were primarily diagnosed with breast cancer (61.5%) and had a mean VO2peak of 20.1±4.6 ml/kg/min. Enjoyment slightly favoured HIIE (92.9 vs. 89.5 points on a 126-point scale; d=0.15). Intentions to perform HIIE 3 and 5 sessions/week (4.6 and 3.5 points on a 7-point likert scale) were slightly higher than MICE (3.9 and 3.2 points; d=0.30 and 0.12). Task self-efficacy for performing each modality 1-5 times/week favoured MICE (57.7-93.1% confident) over HIIE (47.7-83.1% confident) at a small-to-medium effect (d's=-0.25 to -0.41).
Conclusion: Females living beyond cancer may have slightly more favourable attitudes towards HIIE, yet self-efficacy may be lacking compared to MICE. Researchers and practitioners may consider using both modalities for exercise programming; however, familiarization periods, gradual progressions, and supervision may be needed to enhance self-efficacy around HIIE for females living beyond cancer.