Characterizing enjoyment of high-intensity interval training in association with exercise exertion among inactive women with cardiometabolic risk factors: a randomized crossover study.

Enjoyment across treadmill-based high-intensity interval training (HIIT) is unclear in women with cardiometabolic risk factors. Nineteen inactive women (53±13yrs; 29.1±7.1kg/m2) performed three HIIT protocols in randomized order: 4x4-min (80% volume of oxygen consumption reserve [VO2R]), 10x1-min (90%VO2R), and 8x15-sec (110%VO2R). Heart rate, rating of perceived exertion (RPE), and exercise enjoyment (short-form Physical Activity Enjoyment Scale ~5-min post-exercise) were assessed. The 4x4-min protocol elicited higher heart rate and RPE and lower enjoyment than other protocols (p<0.05). Enjoyment did not differ between 10x1-min and 8x15-sec (p>0.05), although 10x1-min elicited greater exertion (p<0.05). The 10x1-min protocol may balance enjoyment and exertion. ClinicalTrials.gov: NCT05758857.