The Effect of 12-week Circuit Training on Insulin Sensitivity and Endothelial Function in Women With Insulin Resistance

NCT04528693 | Completed

• 1 other identifier: PoznanUPhyEd no. 4
• Study Type: interventional
• Target: 49
• Locations: 1 country
• Sites: 1

Brief Summary

During the last 10 years many studies concerning the impact of physical training on whole-body insulin sensitivity have been published, but there is a lack of an extended investigation on the potential clinical benefits of novel circuit training-based on strength and endurance exercises-relating to the optimization of insulin sensitivity and vascular endothelial function. It is of interest to precisely determine the physiological and biochemical effects of circuit training. An important aspect of the planned research will be the analysis of the effects of physical training on the released during muscle contraction myokines capable of modulating various metabolic processes. We hypothesized that in studied participants 12 weeks of the novel form of training would result in improving insulin sensitivity and vascular endothelial function mainly via myokines released by contracting skeletal muscles. The following questions will be asked: (1) whether the 12-week circuit training (combined strength and endurance exercises) performed by women with insulin resistance, improves insulin sensitivity, carbohydrate and lipid metabolism and promotes the efficiency of endothelial defense mechanisms? (2) whether the 12-week circuit training (combined of strength and endurance exercises) changes the concentrations of transcription factors regulating lipid and carbohydrate metabolism or the synthesis and/or secretion of myokines and adipokines in women with insulin resistance? (3) whether the 12-week strength training, interspersed with bouts of endurance exercise has a positive effect on cytokine profile? (4) whether there is a relationship between changes in body composition, HOMA-IR, and the level of myokines caused by physical training? (5) whether the 12-week circuit training reduces low back pain symptoms, plantar stifness and improve functioning of the patient in everyday life? A group of 80 women, aged 25 to 45 years, with diagnosed insulin resistance will participate in the planned study. Participants will be enrolled in the research program based on medical qualification. Before the intervention all women will have venous blood collected to determine fasting glucose, hemoglobin glycosylated (HbA1C) and insulin levels and insulin resistance by the homeostasis model assessment of insulin resistance (HOMA-IR) will be calculated. The inclusion criteria will be as follows: (1) women, age: 25-45 years, menstruating, (2) BMI 18,5-29,9 kg/m2, (3) insulin resistance based on HOMA-IR (cut-off point 2.5), (4) HbA1C ≤ 6.5%, (5) not contraindicated to physical activity. Participants meeting the inclusion criteria will be randomly divided into two groups. The first group of women will undergo circuit training, consisting of exercises performed on 7 machines arranged in a circuit. Thanks to the use of adequate software the machines will automatically adjust their parameters, such as seat height or resistance to the exercising person, and the training progress will be individually monitored. The planned training will last for 3 months, during which the patients will exercise 3 times a week for 30 minutes (2 circuits will be done during each session). The planned duration of the training session will be controlled (one minute for strength exercises, four minutes for endurance exercises and a 30-second break between each exercise). In the training group, one-repetition maximum exercise test (1RM) will be performed to determine the appropriate training load and later after the program to verify the increase in muscle strength. The range of maximum heart rate (HRmax) will also be determined in all exercising women. The second group of women, who will be asked to maintain their current level of physical activity and their diet for a period of 3 months will serve as a control group. Before and after the training program in all participants of the study pulse wave velocity, anthropometric parameters and body composition will be assessed. Concurrently venous blood will be taken to determine biochemical indicators related to carbohydrate and lipid metabolism, insulin resistance, vascular endothelium function, inflammation and adipocytokines and myokines. In both groups of women, the questioners concerning dietary intake and the level of daily physical activity will be administered. Results will be subjected to analysis involving descriptive, and advanced statistic method among them analysis of correlations, regression, variance and cluster analysis. All calculations and statistics will be performed using TIBCO Statistica 13.3 software (TIBCO).

Conditions

Insulin Resistance

Keywords

circuit training; combined training; endothelial function; insulin sensitivity; lipid metabolism; inflammation; myokines; plantar stifness; back pain

Outcome Measures

Primary Outcomes (24)

• Homeostasis model assessment of insulin resistance (HOMA-IR)

  pre-intervention

• Homeostasis model assessment of insulin resistance (HOMA-IR)

  48 hours after the intervention

• HbA1C [mmol/mol]

  ELISA

  pre-intervention

• HbA1C [mmol/mol]

  ELISA

  48 hours after the intervention

• Insuline [mU/ml]

  Radioimmunoassay

  pre-intervention

• Insuline [mU/ml]

  Radioimmunoassay

  48 hours after the intervention

• Systolic and diastolic blood pressure [mmHg]

  pre-intervention

• Systolic and diastolic blood pressure [mmHg]

  48 hours after the intervention

• Pulse wave velocity (PWV) [m/s]

  PWV will be performed using the SphygmoCor Px (Atcor Medical Blood Pressure Analysis System, Sydney, Australia.

  pre-intervention

• Pulse wave velocity (PWV) [m/s]

  PWV will be performed using the SphygmoCor Px (Atcor Medical Blood Pressure Analysis System, Sydney, Australia.

  48 hours after the intervention

• Glucose, Total cholesterol (TC), high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C) and triglycerides (TG) [mmol/l]

  Dimension Flex Reagent Cartridge

  pre-intervention

• Glucose, Total cholesterol (TC), high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C) and triglycerides (TG) [mmol/l]

  Dimension Flex Reagent Cartridge

  48 hours after the intervention

• Irisin, Visfatin, Retinol-binding protein 4 (RBP-4) [pg/ml]

  ELISA

  pre-intervention

• Irisin, Visfatin, Retinol-binding protein 4 (RBP-4) [pg/ml]

  ELISA

  48 hours after the intervention

• Apelin [ng/ml]

  ELISA

  pre-intervention

• Apelin [ng/ml]

  ELISA

  48 hours after the intervention

• C Reactive Protein (hsCRP) [mg/l]

  ELISA

  pre-intervention

• C Reactive Protein (hsCRP) [mg/l]

  ELISA

  48 hours after the intervention

• Interleukin-6 (IL-6), Interleukin-10 (IL-10) [pg/ml]

  ELISA

  pre-intervention

• Interleukin-6 (IL-6), Interleukin-10 (IL-10) [pg/ml]

  ELISA

  48 hours after the intervention

• Endothelial nitric oxide synthase (eNOS) [ng/ml]

  ELISA

  pre-intervention

• Endothelial nitric oxide synthase (eNOS) [ng/ml]

  ELISA

  48 hours after the intervention

• Muscle strength [kg]

  Test 1RM will be performed for following groups of muscles: abdominal muscles; back of the thigh (biceps femoris muscle and muscles adjacent to it); latissimus dorsi muscle, shoulder girdle muscles and upper chest; erector spinae and other muscles of a back; gluteal muscles, hip adductor and abductor muscles.

  pre-intervention

• Muscle strength [kg]

  Test 1RM will be performed for following groups of muscles: abdominal muscles; back of the thigh (biceps femoris muscle and muscles adjacent to it); latissimus dorsi muscle, shoulder girdle muscles and upper chest; erector spinae and other muscles of a back; gluteal muscles, hip adductor and abductor muscles.

  48 hours after the intervention

Secondary Outcomes (8)

• Plantar stiffness [N/m]

  pre-intervention

• Plantar stiffness [N/m]

  48 hours after the intervention

• State of tension of erector spinae muscles [Hz]

  pre-intervention

• State of tension of erector spinae muscles [Hz]

  48 hours after the intervention

• Low back pain intensity: questionnaire

  pre-intervention

Study Arms (2)

Intervention

EXPERIMENTAL

40 women with insulin resistance aged 25-45, BMI 18,5-29,9 will perform, for a period of 3 months, 3 times a week, strength training, interspersed with bouts of endurance exercise carried out on circuit machines integrated with the Milon computer software.

Behavioral: Circuit training (combination of strength and endurance exercises)

Control

NO INTERVENTION

40 women with insulin resistance aged 25-45, BMI 18,5-29,9 will be asked to maintain their current level of physical activity and their diet for a period of 3 months.

Interventions

Circuit training (combination of strength and endurance exercises) BEHAVIORAL

The intervention will last 3 months, exercises will take place 3 times a week and will consist of strength exercises, interspersed with bouts of endurance exercise carried out on circuit machines integrated with the Milon computer software for a total of 30 minutes per session.

Also known as: Circuit training on machines integrated with the Milon computer software

Intervention

Eligibility Criteria

• Age: 25 Years - 45 Years
• Sex: female
• Healthy Volunteers: No
• Age Groups: Adult (18-64)

You may qualify if:

• women,
• age: 25-45years,
• menstruating,
• BMI 18,5-29,9 kg/m2,
• insulin resistance based on HOMA -IR (cut-off point 2.5),
• not contraindicated to physical activity.

You may not qualify if:

• type 1 and 2 diabetes,
• poorly controlled hypertension (mean SBP \>140mmHg and/or mean DBP \>90mmHg) over the last month and/or need to modify the pharmacological treatment,
• obesity: BMI \> 30 kg/m2,
• lipid disorders requiring implementation of pharmacological treatment in the last 3 months before or during observation,
• a positive history of ischemic heart disease, carotid atherosclerosis and / or lower limb atherosclerosis,
• clinically significant arrhythmias or conduction disorders,
• chronickidney disease,
• clinically significant liver dysfunction,
• acute or chronic, clinically manifest inflammatory process,
• an acute infection in the last month,
• cancer,
• taking medication that could interfere with the results of the tests,
• other conditions that may pose any risk to the patient during the observation.

Sponsors & Collaborators

• Poznan University of Physical Education: lead
• Poznan University of Medical Sciences: collaborator

Study Sites (1)

Poznan University of Physical Education

Poznan, 61-871, Poland

Location

Related Publications (7)

• Srikanthan P, Karlamangla AS. Relative muscle mass is inversely associated with insulin resistance and prediabetes. Findings from the third National Health and Nutrition Examination Survey. J Clin Endocrinol Metab. 2011 Sep;96(9):2898-903. doi: 10.1210/jc.2011-0435. Epub 2011 Jul 21.

  PMID: 21778224 BACKGROUND

• Bird SR, Hawley JA. Update on the effects of physical activity on insulin sensitivity in humans. BMJ Open Sport Exerc Med. 2017 Mar 1;2(1):e000143. doi: 10.1136/bmjsem-2016-000143. eCollection 2016.

  PMID: 28879026 BACKGROUND

• Lambers S, Van Laethem C, Van Acker K, Calders P. Influence of combined exercise training on indices of obesity, diabetes and cardiovascular risk in type 2 diabetes patients. Clin Rehabil. 2008 Jun;22(6):483-92. doi: 10.1177/0269215508084582.

  PMID: 18511528 BACKGROUND

• Oh KJ, Lee DS, Kim WK, Han BS, Lee SC, Bae KH. Metabolic Adaptation in Obesity and Type II Diabetes: Myokines, Adipokines and Hepatokines. Int J Mol Sci. 2016 Dec 22;18(1):8. doi: 10.3390/ijms18010008.

  PMID: 28025491 BACKGROUND

• Ormazabal V, Nair S, Elfeky O, Aguayo C, Salomon C, Zuniga FA. Association between insulin resistance and the development of cardiovascular disease. Cardiovasc Diabetol. 2018 Aug 31;17(1):122. doi: 10.1186/s12933-018-0762-4.

  PMID: 30170598 BACKGROUND

• Karolkiewicz J, Krzywicka M, Szulinska M, Musialik K, Musialowska D, Zielinski J, Bilska A, Ratajczak M. Effects of a Circuit Training Program on Myokine Levels in Insulin-Resistant Women: A Randomised Controlled Trial. J Diabetes Res. 2024 Nov 28;2024:6624919. doi: 10.1155/jdr/6624919. eCollection 2024.

  PMID: 39640300 DERIVED

• Ratajczak M, Krzywicka M, Szulinska M, Musialowska D, Kusy K, Karolkiewicz J. Effects of 12-Week Combined Strength and Endurance Circuit Training Program on Insulin Sensitivity and Retinol-Binding Protein 4 in Women with Insulin-Resistance and Overweight or Mild Obesity: A Randomized Controlled Trial. Diabetes Metab Syndr Obes. 2024 Jan 6;17:93-106. doi: 10.2147/DMSO.S432954. eCollection 2024.

  PMID: 38204866 DERIVED

MeSH Terms

Conditions

Insulin Resistance; Inflammation; Back Pain

Interventions

Circuit-Based Exercise

Condition Hierarchy (Ancestors)

Hyperinsulinism; Glucose Metabolism Disorders; Metabolic Diseases; Nutritional and Metabolic Diseases; Pathologic Processes; Pathological Conditions, Signs and Symptoms; Pain; Neurologic Manifestations; Signs and Symptoms

Intervention Hierarchy (Ancestors)

Physical Conditioning, Human; Exercise; Motor Activity; Movement; Musculoskeletal Physiological Phenomena; Musculoskeletal and Neural Physiological Phenomena

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: SINGLE
• Who Masked: CARE PROVIDER
• Masking Details: The qualifying physician does not know which of the examined persons will be allocated in the intervention or in the control group.
• Purpose: BASIC SCIENCE
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: assistant professor

Model Details: The study is designed as a prospective randomized clinical trial where subjects are randomally allocated to intervention group (study) or non-intervention group (control).

Study Record Dates

• First Submitted: August 23, 2020
• First Posted: August 27, 2020
• Study Start: August 17, 2020
• Primary Completion: December 31, 2022
• Study Completion: June 30, 2025
• Last Updated: September 23, 2025

Record last verified: 2025-09

Locations

PL (1)