Resistance Exercise, Metabolism and Time of Day

The Impact of the Time of Day on Metabolic Responses to Resistance Exercise in Adults Who Are Obese or Overweight: a Randomised Controlled Trial

The aim of the current study is to determine the effect of time of day on the muscle and metabolic responses to resistance exercises in obese or overweight adults. To achieve this aim we have the following objectives:

1. Compare the effects of resistance exercise training performed in the morning vs the evening on insulin sensitivity
2. Compare the effects of resistance exercise training performed in the morning vs the evening on gains in muscle mass and strength
3. Compare the acute glucose responses to resistance exercise performed in the morning vs the evening

Study Overview

• Status: Completed
• Conditions: Metabolic Disease
• Intervention / Treatment: Behavioral: Exercise training

• Study Type: Interventional
• Enrollment (Actual): 36
• Phase: Not Applicable

Contacts and Locations

Study Locations

• United Kingdom
  • Glasgow, United Kingdom
    • Stuart Robert Gray

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years to 45 years (Adult)
• Accepts Healthy Volunteers: Yes

Description

Inclusion Criteria:

• pass the physical activity readiness questionnaire
• body mass index (BMI) >27kg/m² and limited to 40 kg/m².

Exclusion Criteria:

• Prior surgery for weight loss
• Prior history of heart, lung, cancer, endocrine or liver disease
• Participating in more than 1 hour structured exercise training per week

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Basic Science
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: None (Open Label)

Number of Arms

3

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
No Intervention: Control; Habitual physical activity
Experimental: Morning exercise; Exercise training in the morning (6:00-10:00am)	Behavioral: Exercise training; Exercise will consist of 1 set x 9 exercises x 3 sessions per week x 6 weeks. The load to be used during training will be calculated as 80% of one-repetition maximum (1RM) with each set performed to failure. 1RM will be re-tested on week 3, and the load adjusted accordingly, and upon completion of the study. During the training period, all sessions of training will be supervised by the researcher. The following exercises will be performed: Bench press, biceps curl, lat pull down, overhead press, lateral raise, leg extension, leg curl and calf raise.
Experimental: Evening exercise; Exercise training in the evening (4:00-8:00pm)	Behavioral: Exercise training; Exercise will consist of 1 set x 9 exercises x 3 sessions per week x 6 weeks. The load to be used during training will be calculated as 80% of one-repetition maximum (1RM) with each set performed to failure. 1RM will be re-tested on week 3, and the load adjusted accordingly, and upon completion of the study. During the training period, all sessions of training will be supervised by the researcher. The following exercises will be performed: Bench press, biceps curl, lat pull down, overhead press, lateral raise, leg extension, leg curl and calf raise.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change in insulin sensitivity	Insulin sensitivity calculated via the Matsuda Index during an oral glucose tolerance test	Change from baseline to 6 weeks

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change in vastus lateralis muscle thickness	Muscle thickness of the vastus lateralis muscle measured via ultrasound	Change from baseline to 6 weeks
Change in whole body lean mass	whole body lean mass measured via bio-electrical impedance	Change from baseline to 6 weeks
Change in whole body fat mass	whole body fat mass measured via bio-electrical impedance	Change from baseline to 6 weeks
Change in one-repetition maximum muscle strength	Sum of one-repetition maximum of Bench press, biceps curl, lat pull down, overhead press, lateral raise, leg extension, leg curl and calf raise exercise	Change from baseline to 6 weeks
Change in knee extensor maximal isometric torque	Knee extensor maximal isometric torque measured during a maximal voluntary contraction	Change from baseline to 6 weeks
Change in grip strength	Grip strength measured with a hand held dynamometer	Change from baseline to 6 weeks
Change in mean glucose levels	Mean glucose levels measured via continuous glucose monitors	Change from baseline to 6 weeks
Change in glucose variability	Glucose variability measured via continuous glucose monitors	Change from baseline to 6 weeks

Collaborators and Investigators

• Sponsor: University of Glasgow

Study record dates

Study Major Dates

• Study Start (Actual): May 1, 2022
• Primary Completion (Actual): February 1, 2024
• Study Completion (Actual): February 1, 2024

Study Registration Dates

• First Submitted: April 1, 2022
• First Submitted That Met QC Criteria: April 1, 2022
• First Posted (Actual): April 11, 2022

Study Record Updates

• Last Update Posted (Actual): March 30, 2025
• Last Update Submitted That Met QC Criteria: March 25, 2025
• Last Verified: March 1, 2025

More Information

Terms related to this study

• Keywords: exercise; muscle; circadian; metabolism
• Additional Relevant MeSH Terms: Metabolic Diseases
• Other Study ID Numbers: 200210068

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No
• product manufactured in and exported from the U.S.: No