HIIT in Isolated IFG: A Proof-of-Concept Study

Intervention participants will complete 24 supervised high-intensity interval training (HIIT) sessions over 8 weeks, with 3 sessions per week on alternate days. Each HIIT session will consist of a 5-minute warm-up, followed by an interval-based workout phase that includes steady up-tempo cadences, sprints, and climbs, interspersed with recovery periods. The session will conclude with a 5-minute cooldown. The workout sessions will initially last 20 minutes and will progressively increase in time based on participants\' tolerance and instructor recommendations. Intensity will start at 75% of estimated maximal heart rate reserve and will increase by 5% weekly, as tolerated and/or deemed necessary by the instructor, over the 8-week intervention period. Participants will receive instructions to maintain a eucaloric diet throughout the study.

Control participants will be instructed to refrain from engaging in intense physical activities during the study period. They will also receive instructions to maintain a eucaloric diet throughout the study.

The continuous glucose monitoring (CGM) system comprises a sensor, a transmitter, and a receiver. The sensor measures interstitial fluid glucose levels every 5 minutes, and the transmitter wirelessly sends this glucose data to the receiver. Both intervention and control participants will wear the CGM device in a blinded mode for 10 days before starting the intervention, throughout the 8-week intervention period, and for 10 days post-intervention.