Exercise and Tissue-Specific Insulin Sensitivity in South Asian and Nordic Women With Previous Gestational Diabetes

NCT07843082 | Completed

• 2 other identifiers: 758180NNF23OC0082123
• Study Type: interventional
• Target: 43
• Locations: 1 country
• Sites: 1

Brief Summary

South Asian women have a high risk of developing type 2 diabetes, and the risk is particularly high after gestational diabetes. This study examined whether eight weeks of supervised vigorous exercise improves insulin sensitivity in South Asian women with previous gestational diabetes, and whether the response differs from that of Nordic women with the same history. Participants trained four times per week, with two whole-body resistance sessions and two high-intensity interval cycling sessions. Before and after the intervention, insulin sensitivity was measured with an oral glucose tolerance test combined with stable-isotope tracers, and cardiorespiratory fitness, muscle strength and body composition were assessed. Blood, urine and tissue samples were collected for multi-omics analyses.

Conditions

Diabetes; Obesity & Overweight

Keywords

south asian; prediabetes; exercise; insulin resistance; women; gestational diabetes

Outcome Measures

Primary Outcomes (8)

• Change in postprandial whole-body insulin sensitivity measured as glucose metabolic clearance rate per unit insulin (MCR/I)

  Whole-body (predominantly skeletal muscle) insulin sensitivity assessed during a 75 g oral glucose tolerance test combined with a 6-hour triple stable-isotope tracer study: a primed continuous intravenous infusion of \[6,6-2H2\]glucose and \[1,1,2,3,3-2H5\]glycerol, plus 2.5 g oral \[U-13C\]glucose. Insulin sensitivity is expressed as the postprandial glucose metabolic clearance rate relative to the corresponding plasma insulin concentration (MCR/I, mL/min/kg per nmol/L). Higher values indicate greater insulin sensitivity. The outcome is the change from baseline to the end of the 8-week exercise intervention.

  Baseline and 8 weeks (at the end of the 8-week exercise intervention)

• Change in fasting whole-body insulin sensitivity measured as glucose metabolic clearance rate per unit insulin (MCR/I)

  Fasting whole-body insulin sensitivity assessed during a 6-hour triple stable-isotope tracer study with a primed continuous intravenous infusion of \[6,6-2H2\]glucose and \[1,1,2,3,3-2H5\]glycerol. Insulin sensitivity is expressed as the fasting glucose metabolic clearance rate relative to the corresponding plasma insulin concentration (MCR/I, mL/min/kg per nmol/L). Higher values indicate greater insulin sensitivity. The outcome is the change from baseline to the end of the 8-week exercise intervention.

  Baseline and 8 weeks (at the end of the 8-week exercise intervention)

• Change in suppression of endogenous glucose production (EGP) during oral glucose tolerance test

  Hepatic insulin sensitivity assessed as the suppression of endogenous glucose production (EGP) during a 75 g oral glucose tolerance test combined with a 6-hour triple stable-isotope tracer study. EGP is calculated with the Steele non-steady-state one-compartment model from \[6,6-2H2\]glucose and oral \[U-13C\]glucose enrichments. The outcome is the absolute suppression of EGP from the fasting value during the test, expressed in mmol/min/kg. Greater suppression indicates greater hepatic insulin sensitivity. The outcome is the change from baseline to the end of the 8-week exercise intervention.

  Baseline and 8 weeks (at the end of the 8-week exercise intervention)

• Change in duration of suppression of endogenous glucose production (EGP) during oral glucose tolerance test

  Duration of hepatic insulin action assessed during a 75 g oral glucose tolerance test combined with a 6-hour triple stable-isotope tracer study. Endogenous glucose production (EGP) is calculated with the Steele non-steady-state one-compartment model from \[6,6-2H2\]glucose and oral \[U-13C\]glucose enrichments. The outcome is the time for which EGP remains suppressed below the fasting rate, expressed in minutes. Longer duration indicates more sustained hepatic insulin action. The outcome is the change from baseline to the end of the 8-week exercise intervention.

  Baseline and 8 weeks (at the end of the 8-week exercise intervention)

• Change in suppression of glycerol rate of appearance (Ra) during oral glucose tolerance test

  Adipose tissue insulin sensitivity assessed as the suppression of lipolysis during a 75 g oral glucose tolerance test combined with a 6-hour triple stable-isotope tracer study. Whole-body glycerol rate of appearance (Ra) is calculated with the Steele non-steady-state one-compartment model from a primed continuous infusion of \[1,1,2,3,3-2H5\]glycerol. The outcome is the absolute suppression of glycerol Ra from the fasting value over the first 60 minutes of the test, expressed in mmol/min/kg. Greater suppression indicates greater adipose tissue insulin sensitivity. The outcome is the change from baseline to the end of the 8-week exercise intervention.

  Baseline and 8 weeks (at the end of the 8-week exercise intervention)

• Change in duration of suppression of glycerol rate of appearance (Ra) during oral glucose tolerance test

  Duration of adipose tissue insulin action assessed during a 75 g oral glucose tolerance test combined with a 6-hour triple stable-isotope tracer study. Whole-body glycerol rate of appearance (Ra) is calculated with the Steele non-steady-state one-compartment model from a primed continuous infusion of \[1,1,2,3,3-2H5\]glycerol. The outcome is the time for which glycerol Ra remains suppressed below the fasting rate, expressed in minutes. Longer duration indicates more sustained suppression of lipolysis. The outcome is the change from baseline to the end of the 8-week exercise intervention.

  Baseline and 8 weeks (at the end of the 8-week exercise intervention)

• Change in hepatic insulin resistance index (Hepatic IR)

  Hepatic insulin resistance assessed in the fasting state during a 6-hour triple stable-isotope tracer study. The hepatic insulin resistance index (Hepatic IR) is calculated as fasting endogenous glucose production multiplied by the fasting plasma insulin concentration, following Gastaldelli 2022, and is expressed in mmol/min/kg x pmol/L. Endogenous glucose production is derived with the Steele non-steady-state one-compartment model from a primed continuous infusion of \[6,6-2H2\]glucose. Higher values indicate greater hepatic insulin resistance. The outcome is the change from baseline to the end of the 8-week exercise intervention.

  Baseline and 8 weeks (at the end of the 8-week exercise intervention)

• Change in adipose tissue insulin resistance index (Lipo-IR)

  Adipose tissue insulin resistance assessed in the fasting state during a 6-hour triple stable-isotope tracer study. The adipose tissue insulin resistance index (Lipo-IR) is calculated as the product of fasting glycerol rate of appearance and the fasting plasma insulin concentration, following Gastaldelli 2022, and is expressed in mmol/min/kg x pmol/L. Glycerol rate of appearance is derived with the Steele non-steady-state one-compartment model from a primed continuous infusion of \[1,1,2,3,3-2H5\]glycerol. Higher values indicate greater adipose tissue insulin resistance. The outcome is the change from baseline to the end of the 8-week exercise intervention.

  Baseline and 8 weeks (at the end of the 8-week exercise intervention)

Secondary Outcomes (13)

• Change in maximal oxygen uptake (VO2max) measured by graded cardiopulmonary exercise test on a cycle ergometer

  Baseline and 8 weeks (at the end of the 8-week exercise intervention)

• Change in maximal upper body strength measured as one-repetition maximum (1RM) in chest press

  Baseline and 8 weeks (at the end of the 8-week exercise intervention)

• Change in maximal lower body strength measured as one-repetition maximum (1RM) in leg press

  Baseline and 8 weeks (at the end of the 8-week exercise intervention)

• Sustained change in 2-hour plasma glucose during 75 g oral glucose tolerance test at 12-month follow-up

  Baseline, 8 weeks, and 12 months after completion of the 8-week exercise intervention

• Sustained change in fat mass measured by bioelectrical impedance analysis at 12-month follow-up

  Baseline, 8 weeks, and 12 months after completion of the 8-week exercise intervention

Study Arms (1)

Exercise

EXPERIMENTAL

All participants received the same supervised exercise programme: eight weeks of combined resistance and high-intensity aerobic training, four sessions per week. Both ethnic groups (South Asian and Nordic) followed the identical regime.

Behavioral: Exercise

Interventions

Exercise BEHAVIORAL

Eight weeks of supervised training with four sessions per week: two whole-body resistance training sessions and two high-intensity interval cycling sessions, totalling approximately five hours of vigorous exercise per week. Resistance sessions comprised three lower-body and six upper-body exercises, 1-4 sets per exercise, progressing from 19 sets in the first sessions to 28 sets in the last sessions. Each set consisted of 12 repetitions during weeks 1-3 and 10 repetitions during weeks 4-8, with 1-4 repetitions in reserve. Interval sessions were performed on a cycle ergometer. One weekly session used 7-minute bouts at 82-87% of maximal heart rate with 3 minutes of rest between bouts, progressing from 3 to 5 bouts. The other weekly session used 2-minute bouts at an intensity reaching at least 90% of maximal heart rate during the final 30 seconds, with 2 minutes of rest between bouts, progressing from 6 to 9 bouts.

Exercise

Eligibility Criteria

• Age: 18 Years+
• Sex: female
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• Woman aged 18 years or older
• Previous gestational diabetes
• South Asian or Nordic origin, with both parents of the same ethnic background

You may not qualify if:

• Known type 1 or type 2 diabetes
• Use of glucose-lowering medication, or other drugs known to interfere with glucose or lipid metabolism or with the response to exercise
• Pregnancy
• Liver, renal, cardiopulmonary, oncological or other debilitating disease that could jeopardise participant safety or compliance with the protocol

Sponsors & Collaborators

• Oslo University Hospital: lead
• University of Oslo: collaborator

Study Sites (1)

Aker sykehus

Oslo, Norway

Location

Related Links

• Website of Oslo Diabetes Research Centre, which hosts the DIASA research programme that this study is part of

MeSH Terms

Conditions

Diabetes Mellitus; Obesity; Overweight; Prediabetic State; Motor Activity; Insulin Resistance; Diabetes, Gestational

Interventions

Exercise

Condition Hierarchy (Ancestors)

Glucose Metabolism Disorders; Metabolic Diseases; Nutritional and Metabolic Diseases; Endocrine System Diseases; Overnutrition; Nutrition Disorders; Body Weight; Signs and Symptoms; Pathological Conditions, Signs and Symptoms; Behavior; Hyperinsulinism; Pregnancy Complications; Female Urogenital Diseases and Pregnancy Complications; Urogenital Diseases

Intervention Hierarchy (Ancestors)

Motor Activity; Movement; Musculoskeletal Physiological Phenomena; Musculoskeletal and Neural Physiological Phenomena

Study Officials

• Sindre Lee-Ødegård, MD, PhD

  Oslo University Hospital

  PRINCIPAL INVESTIGATOR

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: NA
• Masking: NONE
• Purpose: PREVENTION
• Intervention Model: SINGLE GROUP
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Principal Investigator

Study Record Dates

• First Submitted: December 3, 2025
• First Posted: September 25, 2026
• Study Start: October 1, 2024
• Primary Completion: September 1, 2025
• Study Completion: September 1, 2026
• Last Updated: September 25, 2026

Record last verified: 2026-09

Data Sharing

• IPD Sharing: Will not share

Locations

NO (1)