A Pilot Study on In-Task Affect Predicting Free-Living Adherence to HIIT and MICT

Area of Science:

• Exercise Science
• Behavioral Medicine
• Public Health

Background:

• Supervised exercise programs are crucial for improving physical activity levels, especially in populations like adults with prediabetes.
• Understanding the psychological factors influencing exercise adherence, such as in-task affect, is vital for designing effective interventions.
• Both moderate-intensity continuous training (MICT) and high-intensity interval training (HIIT) are established exercise modalities, but their impact on affect and subsequent physical activity may differ.

Purpose of the Study:

• To investigate whether in-task affect during supervised exercise predicts changes in moderate-to-vigorous physical activity (MVPA) at 1- and 6-month follow-ups.
• To compare the predictive utility of in-task affect on MVPA between MICT and HIIT interventions.
• To provide pilot data on the relationship between exercise-induced feelings and long-term physical activity maintenance.

Main Methods:

• A pilot experimental study randomized 32 inactive adults with prediabetes to a 2-week supervised MICT or HIIT program with behavioral counseling.
• In-task affect was assessed using the Feeling Scale (FS) at specific time points during exercise sessions.
• Objective physical activity was measured using accelerometers at 1- and 6-month post-intervention to determine changes in MVPA (Total and bouts ≥ 10 minutes).

Main Results:

• In-task affect did not predict changes in total MVPA from baseline to 1 and 6 months across both conditions.
• However, negative in-task affect was found to predict a decrease in MVPA in bouts of ≥ 10 minutes (MVPA10+) over time, specifically within the MICT group.
• No significant difference was observed in the utility of in-task affect for predicting MVPA-Total between HIIT and MICT.

Conclusions:

• Preliminary evidence suggests that negative affect experienced during moderate-intensity continuous training may hinder the maintenance of longer bouts of physical activity.
• In-task affect's role in predicting overall physical activity levels (MVPA-Total) did not differ between HIIT and MICT in this pilot study.
• Larger-scale studies are warranted to confirm these findings and explore the nuanced relationship between exercise affect and physical activity adherence.