Analysis of Ergogenic Potential and Risks Associated With Acute and Chronic Use of Sulphonylureas on Physical Exercise

June 20, 2020 updated by: Jocelito Bijoldo Martins, Instituto de Cardiologia do Rio Grande do Sul
This study have like aim to examine whether insulin secretagogues have a potential ergogenic effect leading to a better exercise performance and post-exercise recovery in healthy individuals after a resistance training session. METHODS: This is a randomized, double-blind, placebo-controlled, clinical trial. The sample will consist of 44 men. Subjects will be randomly allocated (block randomization, www.randomizer.org) to the following groups: placebo (PFG, n=22) and sulphonylurea (GFS, n=22). The study will consist of 3 visits 7 days apart. On visit 1 the participants will ask to sign an informed consent form and will carry out medical evaluation with anthropometric assessment. At that visit they will perform a one-repetition maximum test of the upper limbs by using the horizontal bench press and of the lower limbs by using the 45º leg press. On visit 2, they will perform a second round of similar 1-RM tests to determine workloads for the study session [sulphonylurea (gliclazide) vs. placebo]. The experimental exercise session will be held on visits 3. Gliclazide modified release 60 mg (Diamicron® MR) or placebo (starch, sodium lauryl sulfate and Aerosil) will be orally administered as matched capsules (same color, flavor, smell and size) 8 hours before the beginning of exercise session, double-blind. In the experimental session, first, warm-up on the bench press and leg press, both with workload at 50% of 1-RM will be carried out. After a 2-minute rest, the resistance training session will be started. It will consist of 4 sets of bench press and leg press exercises at 65% of 1-RM with maximum repetitions until concentric failure. The bench press exercises will be followed by the leg press exercises with no interval between them. A 2-minute interval will allowed after each series of exercises. Measurements for heart rate (HR) and Visual Analogue Scale (VAS) for Pain will be taken before, between each series of exercises and 24 and 48 hours after session. Venous blood samples will be obtained before, immediately after, 24 and 48 hours after, for determining serum levels of creatine kinase isoenzyme MM and lactate dehydrogenase. Capillary blood for glucose determination will be collected from the digital pulp using a glucometer before and immediately after. Resistance training volume will be calculated for each type of exercise as well as total training volume for each session as a product of exercise workload and number of series and repetitions.

Study Overview

Status

Status

Indicates the current recruitment status or the expanded access status.
Unknown

Conditions

Conditions

The disease, disorder, syndrome, illness, or injury that is being studied. On ClinicalTrials.gov, conditions may also include other health-related issues, such as lifespan, quality of life, and health risks.

Intervention / Treatment

Intervention / Treatment

A process or action that is the focus of a clinical study. Interventions include drugs, medical devices, procedures, vaccines, and other products that are either investigational or already available. Interventions can also include noninvasive approaches, such as education or modifying diet and exercise.

Detailed Description

The use of performance-enhancing drugs is a major area of concern for high-performance athletes because it may lead to serious health problems. It is also quite concerning that these substances are also widely used without guidance among non-athletes for faster results and aesthetic reasons. Several substances used for doping in sports have well-established ergogenic and side effects. Studies have shown that insulin is used for its anabolic effects mostly among recreational and professional weightlifters and bodybuilders. Currently, insulin and its analogs are on the WADA list of prohibited substances for their anabolic effects mostly in muscle tissues and side effects. However, a class of drugs known as insulin secretagogues are used by some athletes to enhance performance. Few studies have examined the potential effects of insulin secretagogues, especially sulfonylureas, on exercise performance and post-exercise recovery among athletes as well as their potential side effects. Despite insufficient data supporting the use of insulin secretagogues as ergogenic supplement well as well its associated risks, these substances have been empirically used for both, acute and chronic effects among professional athletes and non-athletes. Thus, the present study have like aim to examine whether insulin secretagogues have a potential ergogenic effect leading to a better exercise performance and post-exercise recovery in healthy individuals after a resistance training session. METHODS: This is a randomized, double-blind, placebo-controlled, clinical trial. The sample will consist of 44 men, young adults, healthy and experienced in strength training and who meet the inclusion and exclusion criteria specified. The sample calculation was determined by a pilot study conducted with 10 subjects, with strength performance as the primary outcome, using drug (Gliclazide) or placebo, taking into account a statistical power of 95% and a significance level of 5%. For this purpose, the GPower 3.1was used. Subjects will be randomly allocated (block randomization, www.randomizer.org) to the following groups: placebo (PFG, n=22) and sulphonylurea (GFS, n=22). The study will consist of 3 visits 7 days apart. On visit 1 the participants will ask to sign an informed consent form and will carry out medical evaluation with anthropometric assessment. At that visit they will perform a one-repetition maximum test of the upper limbs by using the horizontal bench press and of the lower limbs by using the 45º leg press. On visit 2, they will perform a second round of similar 1-RM tests to determine workloads for the study sessions [sulphonylurea (gliclazide) vs. placebo]. The experimental exercise session will be held on visit 3. The participants will ask to follow a personalized food intake plan prescribed by a skilled provider in the 24 hours proceeding both sessions. Gliclazide modified release (MR) or placebo will be orally administered as matched capsules (same color, flavor, smell and size) 8 hours before the beginning of exercise session. Gliclazide 60 mg (Diamicron® MR) or placebo (starch, sodium lauryl sulfate and Aerosil) will administered double-blind. Upon arrival at the study site, the participants will consum a pre-workout snack. The experimental protocol will start 30 minutes later. First, warm-up on the bench press and leg press, both with workload at 50% of 1-RM wil be carried out. After a 2-minute rest, the resistance training session will be started. It will consist of 4 sets of bench press and leg press exercises at 65% of 1-RM with maximum repetitions until concentric failure, with the execution speed of 2x2. The bench press exercises will be followed by the leg press exercises with no interval between them. A 2-minute interval will allowed after each series of exercises. Measurements for heart rate (HR) and Visual Analogue Scale (VAS) for Pain will be taken before, between each series of exercises and 24 and 48 hours after session. Venous blood samples will be obtained before, immediately after, 24 and 48 hours after session for determining serum levels of creatine kinase isoenzyme MM and lactate dehydrogenase using a colorimetric enzymatic assay. Capillary blood for glucose determination will be collected from the digital pulp using a glucometer before and immediately after session. At the end of exercise session, a custom will be offered to prevent potential hypoglycemic events. Resistance training volume will be calculated for each type of exercise as well as total training volume for each session as a product of exercise workload and number of series and repetitions. The data will be present as means ± standard deviation (SD). Repeated measures ANOVA Two Way using Bonferroni post-hoc tests will be used for comparisons between the study drug and placebo over time. All data analyses will be carried out using SPSS 23.0 at a significance level of p<0.05.

Study Type

Study Type

Describes the nature of a clinical study. Study types include interventional studies (also called clinical trials), observational studies (including patient registries), and expanded access.
Interventional

Enrollment (Anticipated)

Enrollment

The number of participants in a clinical study. The "anticipated" enrollment is the target number of participants that the researchers need for the study.
44

Phase

Phase

The stage of a clinical trial studying a drug or biological product, based on definitions developed by the U.S. Food and Drug Administration (FDA). The phase is based on the study's objective, the number of participants, and other characteristics. There are five phases: Early Phase 1 (formerly listed as Phase 0), Phase 1, Phase 2, Phase 3, and Phase 4. Not Applicable is used to describe trials without FDA-defined phases, including trials of devices or behavioral interventions.
  • Phase 4

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Contact

Study Contact

The name and contact information for the person who can answer enrollment questions for a clinical study. Each location where the study is being conducted may also have a specific contact, who may be better able to answer those questions.

Study Contact Backup

Study Locations

  • Brazil
    • Rio Grande Do Sul
      • Porto Alegre, Rio Grande Do Sul, Brazil, 90040-371
        • Recruiting
        • Fundação Universitária de Cardiologia/ Instituto de Cardiologia
        • Contact:

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Eligibility Criteria

The key requirements that people who want to participate in a clinical study must meet or the characteristics they must have. Eligibility criteria consist of both inclusion criteria (which are required for a person to participate in the study) and exclusion criteria (which prevent a person from participating). Types of eligibility criteria include whether a study accepts healthy volunteers, has age or age group requirements, or is limited by sex.

Ages Eligible for Study

20 years to 30 years (Adult)

Accepts Healthy Volunteers

No

Genders Eligible for Study

Male

Description

Inclusion Criteria:

  • continuously resistance-trained for 2 years or more
  • minimum frequency of 3 weekly sessions
  • preceding 6 months

Exclusion Criteria:

  • self-reported acute or chronic use of drugs including anabolic androgenic steroids, anti-inflammatory drugs, beta-blockers and exogenous insulin for the last 12 months
  • alcohol intake within 72 hours of the study intervention
  • injuries to bones and muscles preventing physical exercise
  • non-adherence to dietary recommendations as instructed by the research team

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

  • Primary Purpose: Other
  • Allocation: Randomized
  • Interventional Model: Parallel Assignment
  • Masking: Triple

Arms and Interventions

Participant Group / Arm

Participant Group / Arm

A group or subgroup of participants in a clinical trial that receives a specific intervention/treatment, or no intervention, according to the trial's protocol.
Intervention / Treatment

Intervention / Treatment

A process or action that is the focus of a clinical study. Interventions include drugs, medical devices, procedures, vaccines, and other products that are either investigational or already available. Interventions can also include noninvasive approaches, such as education or modifying diet and exercise.
Active Comparator: Sulphonylurea Group
Gliclazide 60 mg (Diamicron® MR) will be orally administered as matched capsules (same color, flavor, smell and size) 8 hours before the beginning of exercise session.
Other: Resistance Training
Both groups will perform the resistance training protocol that will consist of a warm-up on the bench press and leg press, both with workload at 50% of 1-RM. After a 2-minute rest, the resistance training session will be started. It will consist of 4 sets of bench press and leg press exercises at 65% of 1-RM with maximum repetitions until concentric failure, with the execution speed of 2x2. The bench press exercises will be followed by the leg press exercises with no interval between them. A 2-minute interval will allowed after each series of exercises.
Placebo Comparator: Placebo Group
Placebo (starch, sodium lauryl sulfate and Aerosil) will be orally administered as matched capsules (same color, flavor, smell and size) 8 hours before the beginning of exercise session.
Other: Resistance Training
Both groups will perform the resistance training protocol that will consist of a warm-up on the bench press and leg press, both with workload at 50% of 1-RM. After a 2-minute rest, the resistance training session will be started. It will consist of 4 sets of bench press and leg press exercises at 65% of 1-RM with maximum repetitions until concentric failure, with the execution speed of 2x2. The bench press exercises will be followed by the leg press exercises with no interval between them. A 2-minute interval will allowed after each series of exercises.

What is the study measuring?

Primary Outcome Measures

Primary Outcome Measures

In a clinical study's protocol, the planned outcome measure that is the most important for evaluating the effect of an intervention/treatment. Most clinical studies have one primary outcome measure, but some have more than one.
Outcome Measure
Measure Description
Time Frame
Resistance Training Performance
Time Frame: one week
The performance of resistance training will be measured by the volume of training. This measure is obtained by the total load performed by the subject, measured in kilograms (Kg), being a product of the number of repetitions x the number of series and the load lifted by repetition (volume of training (Kg) = workload (Kg) x Repetition (nº) x Series (nº)). (18. Correa CS, Cadore EL, Martins JB, Silva ER, Pinto RS, Oliveira AR, Kruel LFM. The effects of ibuprofen on muscle performance, worload and plasma creatine kinase during strength training session. Medicina Sportiva. 2012;16(1):17-21).
one week
Muscle Recovery Marker 1
Time Frame: one week
Serum levels of creatine kinase isoenzyme MM (CK-MM)
one week
Muscle Recovery Marker 2
Time Frame: one week
Serum levels of lactate dehydrogenase (LDH)
one week

Secondary Outcome Measures

Secondary Outcome Measures

In a clinical study's protocol, a planned outcome measure that is not as important as the primary outcome measure for evaluating the effect of an intervention but is still of interest. Most clinical studies have more than one secondary outcome measure.
Outcome Measure
Measure Description
Time Frame
Subjective Perception Pain
Time Frame: one week
Visual Analogue Scale (VAS) for Pain is a visual scale in which the subject reports how much pain the subject is feeling at the moment. This scale ranges from 0 to 10, where 0 means no pain and 10 means the greatest pain the subject has ever felt. It will be taken before, between each series of exercises and 24 and 48 hours after each session.The smaller the subjective sensation of pain, in this study, it will mean that recovery was faster and / or more effective.(16. Jensen M, Karoly P, Braver S. The measurement of clinical pain intensity: a comparision of six methods. Pain. 1986;27:117-26).
one week
Blood Glucose Concentration
Time Frame: one week
Capillary blood for blood glucose determination will be collected from the digital pulp using a glucometer (Free Style Optium) before and immediately after each session
one week

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Sponsor

Sponsor

The organization or person who initiates the study and who has authority and control over the study.
Instituto de Cardiologia do Rio Grande do Sul

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start (Actual)

Study Start

The actual date on which the first participant was enrolled in a clinical study. The "anticipated" study start date is the date that the researchers think will be the study start date.
June 1, 2020

Primary Completion (Anticipated)

Primary Completion

The date on which the last participant in a clinical study was examined or received an intervention to collect final data for the primary outcome measure. Whether the clinical study ended according to the protocol or was terminated does not affect this date. For clinical studies with more than one primary outcome measure with different completion dates, this term refers to the date on which data collection is completed for all the primary outcome measures. The "anticipated" primary completion date is the date that the researchers think will be the primary completion date for the study.
August 1, 2020

Study Completion (Anticipated)

Study Completion

The date on which the last participant in a clinical study was examined or received an intervention/treatment to collect final data for the primary outcome measures, secondary outcome measures, and adverse events (that is, the last participant's last visit). The "anticipated" study completion date is the date that the researchers think will be the study completion date.
September 1, 2020

Study Registration Dates

First Submitted

First Submitted

The date on which the study sponsor or investigator first submitted a study record to ClinicalTrials.gov. There is typically a delay of a few days between the first submitted date and the record's availability on ClinicalTrials.gov (the first posted date).
May 23, 2020

First Submitted That Met QC Criteria

First Submitted That Met QC Criteria

The date on which the study sponsor or investigator first submits a study record that is consistent with National Library of Medicine (NLM) quality control (QC) review criteria. The sponsor or investigator may need to revise and submit a study record one or more times before NLM's QC review criteria are met. It is the responsibility of the sponsor or investigator to ensure that the study record is consistent with the NLM QC review criteria.
June 20, 2020

First Posted (Actual)

First Posted

The date on which the study record was first available on ClinicalTrials.gov after National Library of Medicine (NLM) quality control (QC) review has concluded. There is typically a delay of a few days between the date the study sponsor or investigator submitted the study record and the first posted date.
June 23, 2020

Study Record Updates

Last Update Posted (Actual)

Last Update Posted

The most recent date on which changes to a study record were made available on ClinicalTrials.gov. There may be a delay between when the changes were submitted to ClinicalTrials.gov by the study's sponsor or investigator (the last update submitted date) and the last update posted date.
June 23, 2020

Last Update Submitted That Met QC Criteria

Last Update Submitted That Met QC Criteria

The most recent date on which the study sponsor or investigator submitted changes to a study record that are consistent with National Library of Medicine (NLM) quality control (QC) review criteria. It is the responsibility of the sponsor or investigator to ensure that the study record is consistent with the NLM QC review criteria.
June 20, 2020

Last Verified

Last Verified

The most recent date on which the study sponsor or investigator confirmed the information about a clinical study on ClinicalTrials.gov as accurate and current. If a study with a recruitment status of recruiting; not yet recruiting; or active, not recruiting has not been confirmed within the past 2 years, the study's recruitment status is shown as unknown.
June 1, 2020

More Information

Terms related to this study

Other Study ID Numbers

Other Study ID Numbers

Identifiers or ID numbers other than the NCT number that are assigned to a clinical study by the study's sponsor, funders, or others. These numbers may include unique identifiers from other trial registries and National Institutes of Health grant numbers.
  • 5649/19

Plan for Individual participant data (IPD)

Plan to Share Individual Participant Data (IPD)?

No

Drug and device information, study documents

Studies a U.S. FDA-regulated drug product

No

Studies a U.S. FDA-regulated device product

No

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

Cookie Settings

We use cookies to ensure that we give you the best experience on our website. For more details carefully read our Privacy and Cookies Policy. ...>>>You can change your preferences or withdraw your consent at any time by deleting the cookies from your website or computer as described in the policy. Please accept it and choose your preferences by ticking the corresponding boxes in the "Manage Settings" section below. Please carefully read our Terms of Service before you proceed with using any part of this website.
«Manage Settings