Combined Inspiratory Muscle Training and Functional High-Intensity Interval Training in Boys With Obesity

NCT07810361 | Not Yet Recruiting

• 1 other identifier: 2026/025
• Study Type: interventional
• Target: 50
• Locations: 1 country
• Sites: 1

Brief Summary

Childhood obesity is associated with reduced cardiorespiratory fitness, impaired exercise tolerance, and altered respiratory mechanics. This randomized controlled trial investigated whether combining inspiratory muscle training with functional high-intensity interval training improves diaphragm morphology, respiratory muscle strength, pulmonary function, aerobic fitness, and functional exercise capacity in boys with obesity. Fifty boys aged 10-12 years were randomly assigned to six weeks of combined inspiratory muscle training and functional high-intensity interval training or usual activity.

Conditions

Obesity & Overweight; Childhood Obesity

Keywords

childhood obesity; inspiratory muscle training; high-intensity interval training; aerobic fitness; exercise-related metabolic health; functional exercise capacity; six-minute walk test; diaphragm thickness

Outcome Measures

Primary Outcomes (3)

• Inspiratory Diaphragm Thickness

  Inspiratory diaphragm thickness (DTins) was measured by ultrasound at the end of maximal inspiration at the zone of apposition of the right hemidiaphragm. Three measurements were obtained and averaged. The measurement represents an ultrasound-derived index of diaphragm morphology.

  6 weeks

• Diaphragm Thickening Fraction

  Diaphragm thickening fraction (DTf) was assessed using diaphragm ultrasonography and calculated as \[(end-inspiratory diaphragm thickness - end-expiratory diaphragm thickness) / end-expiratory diaphragm thickness\] × 100. Measurements were obtained from the right hemidiaphragm at the zone of apposition. Three measurements were obtained in each respiratory phase and averaged for analysis.

  6 weeks

• Expiratory Diaphragm Thickness

  Expiratory diaphragm thickness (DTexp) was measured by ultrasound at the end of maximal expiration at the zone of apposition of the right hemidiaphragm. Three measurements were obtained and averaged. The measurement represents an ultrasound-derived index of diaphragm morphology.

  6 week

Secondary Outcomes (11)

• Maximal Inspiratory Pressure

  6 week

• Maximal Expiratory Pressure

  6 week

• Forced Vital Capacity

  6 week

• Forced Expiratory Volume in One Second

  6 week

• FEV₁/FVC Ratio

  6 week

Study Arms (2)

Combined IMT + Functional HIIT

EXPERIMENTAL

Participants received six weeks of combined inspiratory muscle training and functional high-intensity interval training in addition to their usual daily activities. Inspiratory muscle training was performed five days per week, and functional high-intensity interval training was performed three non-consecutive days per week.

Other: Inspiratory Muscle Training; Other: Functional High-Intensity Interval Training

Usual Activity Control

NO INTERVENTION

Participants continued their habitual daily activities throughout the six-week study period and did not participate in structured exercise or respiratory muscle training. They were instructed not to initiate a new exercise program until study completion.

Interventions

Inspiratory Muscle Training OTHER

Inspiratory muscle training was performed using a threshold pressure-loading device (POWERbreathe). Participants trained once daily, five days per week, for six consecutive weeks. Each session consisted of two sets of 30 inspiratory efforts. Training began at 30% of maximal inspiratory pressure in week 1, with the training load progressively increased by 5% each week to reach 55% of maximal inspiratory pressure in week 6. Training pressure was reassessed weekly, and all sessions were supervised by a certified exercise specialist.

Combined IMT + Functional HIIT

Functional High-Intensity Interval Training OTHER

Functional high-intensity interval training was performed three times per week on non-consecutive days for six weeks. Each session lasted approximately 35-40 minutes and consisted of an approximately 8-minute warm-up, a functional high-intensity interval circuit, and an approximately 5-minute cool-down. The circuit included wall sit, incline push-up, seated knee-to-chest exercise, shadow boxing, Superman exercise, and low-step-up exercise. Training intensity was progressively increased by manipulating work-to-rest ratios and the number of circuit cycles. Perceived exertion was monitored using the Borg CR-10 scale.

Combined IMT + Functional HIIT

Eligibility Criteria

• Age: 10 Years - 12 Years
• Sex: male
• Healthy Volunteers: Yes
• Age Groups: Child (0-17)

You may qualify if:

• Male sex.
• Age 10-12 years.
• \*Obesity according to World Health Organization age- and sex-specific BMI reference criteria.
• No regular participation in structured exercise training during the preceding six months.
• Medical clearance to participate in moderate-to-vigorous physical activity.

You may not qualify if:

• Diagnosed cardiovascular, neuromuscular, orthopaedic, or metabolic conditions that could interfere with exercise participation.
• Chronic respiratory disease, including asthma requiring regular medication.
• Impaired pulmonary function defined as FEV₁/FVC \<75%.
• \*Upper respiratory tract infection within the preceding two weeks.
• Medication use that could affect respiratory function or exercise capacity.
• Previous thoracic surgery.
• Inability to complete the testing procedures.

Sponsors & Collaborators

• Gümüşhane Universıty: lead

Study Sites (1)

Gumushane Üniversity

Trabzon, Gümüşhane Province, 29000, Turkey (Türkiye)

Location

Related Publications (5)

• Kaeotawee P, Udomittipong K, Nimmannit A, Tovichien P, Palamit A, Charoensitisup P, Mahoran K. Effect of Threshold Inspiratory Muscle Training on Functional Fitness and Respiratory Muscle Strength Compared to Incentive Spirometry in Children and Adolescents With Obesity: A Randomized Controlled Trial. Front Pediatr. 2022 Jul 7;10:942076. doi: 10.3389/fped.2022.942076. eCollection 2022.

  PMID: 35874588 BACKGROUND

• Deng Y, Wang X. Effect of high-intensity interval training on cardiorespiratory in children and adolescents with overweight or obesity: a meta-analysis of randomized controlled trials. Front Public Health. 2024 Jan 26;12:1269508. doi: 10.3389/fpubh.2024.1269508. eCollection 2024.

  PMID: 38344230 BACKGROUND

• Caicedo-Trujillo S, Torres-Castro R, Vasconcello-Castillo L, Solis-Navarro L, Sanchez-Ramirez D, Nunez-Cortes R, Vera-Uribe R, Munoz-Munoz I, Barros-Poblete M, Romero JE, Vilaro J. Inspiratory muscle training in patients with obesity: a systematic review and meta-analysis. Front Med (Lausanne). 2023 Nov 27;10:1284689. doi: 10.3389/fmed.2023.1284689. eCollection 2023.

  PMID: 38089877 BACKGROUND

• Vanhelst J, Fardy PS, Salleron J, Beghin L. The six-minute walk test in obese youth: reproducibility, validity, and prediction equation to assess aerobic power. Disabil Rehabil. 2013 Mar;35(6):479-82. doi: 10.3109/09638288.2012.699581. Epub 2012 Jul 10.

  PMID: 22779759 BACKGROUND

• American Thoracic Society/European Respiratory Society. ATS/ERS Statement on respiratory muscle testing. Am J Respir Crit Care Med. 2002 Aug 15;166(4):518-624. doi: 10.1164/rccm.166.4.518. No abstract available.

  PMID: 12186831 BACKGROUND

MeSH Terms

Conditions

Obesity; Overweight; Pediatric Obesity

Condition Hierarchy (Ancestors)

Overnutrition; Nutrition Disorders; Nutritional and Metabolic Diseases; Body Weight; Signs and Symptoms; Pathological Conditions, Signs and Symptoms

Central Study Contacts

Coşkun Yılmaz, Associate professor

CONTACT

+905424427444; coskun.yilmaz@gumushane.edu.tr

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: SINGLE
• Who Masked: OUTCOMES ASSESSOR
• Masking Details: Outcome assessors were blinded to group allocation whenever feasible. The radiologist responsible for diaphragm ultrasonography was blinded to group allocation throughout the study. Participants and exercise intervention personnel were not blinded because of the nature of the behavioral exercise interventions.
• Purpose: SUPPORTIVE CARE
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Associate professor

Model Details: Participants were randomly allocated in a 1:1 ratio to either a combined inspiratory muscle training and functional high-intensity interval training group or a usual-activity control group.

Study Record Dates

• First Submitted: September 1, 2026
• First Posted: September 9, 2026
• Study Start (Estimated): October 20, 2026
• Primary Completion (Estimated): December 15, 2026
• Study Completion (Estimated): December 20, 2026
• Last Updated: September 9, 2026

Record last verified: 2026-09

Data Sharing

• IPD Sharing: Will not share

Locations

TU (1)