Evaluating the best time for resistance exercise to improve insulin sensitivity and sleep

Timing (AM v PM) of Acute Resistance Exercise on Glycemic Control in Older Adults: The Acute T-Rex Study

Not applicable Interventional University of Utah · NCT06366399

This study is testing whether doing resistance exercises in the morning or evening helps people aged 50-74 with overweight or obesity improve their insulin sensitivity and sleep quality.

Quick facts

PhaseNot applicable
Study typeInterventional
Enrollment20 (estimated)
Ages50 Years to 74 Years
SexAll
SponsorUniversity of Utah Academic / other
Locations1 site (Salt Lake City, Utah)
Trial IDNCT06366399 on ClinicalTrials.gov

What this trial studies

This study aims to determine whether morning or evening resistance exercise has different effects on insulin sensitivity and sleep quality in individuals aged 50-74 with overweight or obesity. Participants will engage in a randomized cross-over trial, performing resistance exercises at two different times of the day in a controlled laboratory setting. Each session will be followed by overnight sleep and an oral glucose tolerance test the next day. The hypothesis is that evening exercise may yield greater benefits for insulin sensitivity compared to morning exercise.

Who should consider this trial

Good fit: Ideal candidates are men and women aged 50-74 years with a BMI between 25 and 45 kg/m² who are generally healthy and not meeting recommended activity guidelines.

Not a fit: Patients with uncontrolled cardiovascular or metabolic diseases, sleep disorders, or those currently on weight loss medications may not benefit from this study.

Why it matters

Potential benefit: If successful, this study could help identify optimal exercise timing to improve insulin sensitivity and reduce the risk of Type 2 Diabetes Mellitus.

How similar studies have performed: While the specific timing of resistance exercise has not been extensively studied, previous research has shown that exercise timing can influence metabolic outcomes, suggesting potential for success in this approach.

Eligibility criteria

Show full inclusion / exclusion criteria
Inclusion Criteria:

* Men and women, all ethnicities, aged 50-74 years
* BMI ≥25 kg/m² and \<45 kg/m²
* Weight stable (less than 5% change in the past 6 months)
* Generally healthy individuals
* Not meeting recommended activity guidelines for aerobic or resistance exercise

Exclusion Criteria:

* Uncontrolled cardiovascular, metabolic, renal, or pulmonary disease
* Cancer treatment in the past 5 years
* Untreated thyroid disease or other medical conditions affecting weight or energy metabolism
* Current use of weight loss medication or other medications likely to impact energy balance
* Bariatric surgery or extensive bowel resection in the past 2 years
* Current or recent history (past 2 years) of eating disorder
* Diagnosis of insomnia, sleep apnea, or other sleep and circadian disorders
* Non-English speaking
* HbA1c \>6.5%

Where this trial is running

Salt Lake City, Utah

Study contacts

How to participate

  1. Review the eligibility criteria above with your treating physician.
  2. Visit the official trial page on ClinicalTrials.gov for the most current contact information and recruitment status.
  3. Contact the listed study coordinator or principal investigator to request pre-screening. Pre-screening is free and never obligates you to enroll.
Conditions Diabetes Mellitus, Type 2Insulin ResistanceGlucose IntoleranceSleep DisturbanceOverweight or ObesityInsulin SensitivityResistance ExerciseStrength-training
Last reviewed 2026-06-09 by the Find a Trial editorial team. Information on this page is for educational purposes and is not medical advice. Always consult qualified healthcare professionals about clinical trial participation.