NCT06014684

Timing Exercise Training as Strategy to Improve Insulin Sensitivity and Substrate Metabolism in Men and Woman With Pre-diabetes

• Status: Completed
• Phase: N/A
• Study type: Interventional
• Enrollment: 15 (actual)
• Sponsor: Maastricht University Medical Center · Academic / Other
• Sex: All
• Age: 40 Years – 75 Years
• Healthy volunteers: Accepted

Summary

n a retrospective analysis of an exercise training program performed either in the morning or afternoon, we found that the afternoon training group improved their peripheral insulin sensitivity and fasting plasma glucose levels to a greater extent than the morning group. However, underlying mechanisms are unclear. The primary study endpoint is nocturnal glucose levels measured by a continuous glucose monitor (CGM).

Detailed description

Rationale: Various metabolic processes, including resting metabolic rate, insulin sensitivity and insulin secretion, follow a recurring 24-hour cycle. These rhythms are shown to be disturbed in in pre-diabetes volunteers compared to young healthy volunteers. In a retrospective analysis of an exercise training program performed either in the morning or afternoon, we found that the afternoon training group improved their peripheral insulin sensitivity and fasting plasma glucose levels to a greater extent than the morning group. However, underlying mechanisms are unclear. Objective: The main objective of this study is to determine whether prolonged exercise training in the afternoon (15:00-17:00 PM) differs from exercise training in the morning (07:00-09:00 AM) in improving insulin sensitivity in individuals with pre-diabetes, and to investigate its underlying mechanisms. Study design: The present study is a randomized double arm longitudinal intervention study in a pre and post design. Study population: 24 pre-diabetic individuals (men and postmenopausal women aged 40 - 75 years and with BMI ≥ 25 and ≤ 38 kg/m2) will complete this study (12 participants in the morning training group and 12 participants in the afternoon training group). From experience with similar studies, we estimate a drop-out rate of 20% and a screening failure of 70% (because individuals often do not know they are pre-diabetic). This results in maximally 30 participants that have to be included and 100 participants that have to be screened (maximally). Intervention (if applicable): Participants will perform a 12-weeks supervised high intensity interval training (HIIT) program with three \~30 min exercise sessions per week. Participants will be randomly assigned to the morning or afternoon training time. To assess the outcomes, participants will come to the university for a 43h measurement period both before and after the 12-week training program. Main study parameters/endpoints: The primary study endpoint is nocturnal glucose levels measured by a continuous glucose monitor (CGM). The secondary outcomes are 24h energy and substrate metabolism. Exploratory outcomes are body composition, intrahepatic lipid content and composition, hepatic insulin sensitivity, hepatic glycogen levels, maximal aerobic capacity, skeletal muscle oxidative capacity, visceral and subcutaneous adipose tissue volume, sleeping metabolic rate, blood glucose levels (continuously measured over 7days) and immune responses.

Conditions

• Pre-diabetes
• Overweight and Obesity

Interventions

Type	Name	Description
BEHAVIORAL	Timing of exercise	High Intensity Interval Training (HIIT) program for 12 weeks (3 per week/36 sessions in total)

Timeline

• Start date: 2023-07-13
• Primary completion: 2026-03-31
• Completion: 2026-03-31
• First posted: 2023-08-28
• Last updated: 2026-04-17

Locations

1 site across 1 country: Netherlands