Effect of Post-exercise Nutrition on Glycemia in Women

Not Applicable

Completed

• Conditions: Overweight and Obesity
• Interventions: Behavioral: Greek yogurt; Behavioral: Carbohydrate-based study supplement; Behavioral: Exercise

• Registration Number: NCT05876260
• Lead Sponsor: University of Toronto

Brief Summary

The purpose of this study is to assess whether post-exercise Greek yogurt following a single session of aerobic exercise improves metabolic and musculoskeletal health in women with overweight/obesity.

Detailed Description

Following the acquisition of informed consent, eligibility to participate in the study will be determined using questionnaires. Participants will undergo baseline testing at our laboratory at the University of Toronto to determine cardiorespiratory fitness, body composition and undergo exercise familiarization.

Eligible participants will be assigned, in a random order, to two metabolic trials approximately 4 weeks apart that involve 4 days of controlled diet and exercise. Each trial takes place over 4 days, but participants are not required to come to the laboratory on all days. The two trials involve: 1) Exercise + Greek Yogurt (GY) 2) Exercise + a carbohydrate-based study supplement (SS).

During the 4 day trials, participants consume controlled diets and the study supplements (GY and SS). On 1 of these days participants will perform exercise in our lab followed by the consumption of GY or SS. Various outcomes will be measured throughout the trial, including glycemic control (via continuous glucose monitoring), fat oxidation, appetite and health outcomes in blood samples.

Throughout the duration of the study, participants will be asked to maintain their habitual diet and physical activity patterns, and maintain their current body weight.

Study Timeline

• Study First Submitted: 2023-05-05
• Study First Submitted QC: 2023-05-16
• Study Start: 2023-05-24
• Study First Posted: 2023-05-25
• Status Verified: 2024-05
• Primary Completion: 2024-05-01
• Study Completion: 2024-05-01
• Last Update Submitted: 2024-05-06
• Last Update Posted: 2024-05-07

Recruitment & Eligibility

• Status: COMPLETED
• Sex: Female
• Target Recruitment: 20

Inclusion Criteria

• 18-45 yrs
• BMI ≥27 kg/m2
• Elevated waist circumference (≥88 cm)
• ≤2 structured exercise sessions/week
• Weight stable (within ± 2kg for at least 6 months)
• Experiencing regular natural menstrual cycles
• Non-smoker

Exclusion Criteria

• Allergy to dairy foods
• Diagnosed lactose intolerance or an aversion to foods provided during the study (e.g., post-exercise snacks)
• Previous history of cardiovascular or metabolic disease
• The use of medication for managing blood glucose or lipid metabolism
• Current use of oral contraceptives or use within the last 3 months
• Irregular menstrual cycles (<21 days or >35 days)
• Pregnant or lactating
• Recreational tobacco or cannabis use
• Inability to perform the study exercise protocols
• Actively engaging in a low-carbohydrate diet (e.g., ketogenic, Atkins).

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: CROSSOVER

Arm && Interventions

Group	Intervention	Description
High-intensity interval exercise and post-exercise Greek yogurt (HIIE+GY)	Greek yogurt	Participants will consume greek yogurt following a single session of exercise
High-intensity interval exercise and post-exercise carbohydrate study supplement (HIIE +SS)	Carbohydrate-based study supplement	Participants will consume a carbohydrate-based study supplement following a single session of exercise
High-intensity interval exercise and post-exercise carbohydrate study supplement (HIIE +SS)	Exercise	Participants will consume a carbohydrate-based study supplement following a single session of exercise
High-intensity interval exercise and post-exercise Greek yogurt (HIIE+GY)	Exercise	Participants will consume greek yogurt following a single session of exercise

Primary Outcome Measures

Name	Time	Method
Postprandial glycemia	24 hour post-exercise	Postprandial glucose exposure assessed using continuous glucose monitoring

Secondary Outcome Measures

Name	Time	Method
Fasting glucose concentration	24 hours post-exercise	Venous blood sampling
Fasting insulin resistance	24 hours post-exercise	Homeostasis Model Assessment (HOMA2)
24 hours average glucose	24 hours post-exercise	Average glucose concentration over 24 hours
Nocturnal glucose	6-8 hours	Overnight glucose exposure (area under the curve)
Glycemic variability	24 hours	Coefficient of variation (%CV)
Post-exercise fat oxidation	1, 2 and 3 hours post-exercise	Fat oxidation assessed with indirect calorimetry
Bone metabolism	30, 90, and 180 minutes and 24 hours post-exercise	Serum concentration of OC
Fasting insulin concentration	24 hours post-exercise	Venous blood sampling

Trial Locations

Locations (1)

Jenna Gillen; 🇨🇦 Toronto, Ontario, Canada