ACUTE EFFECTS OF INSPIRATORY MUSCLE WARM-UP ON INSPIRATORY MUSCLE STRENGTH DURING AEROBIC AND ANAEROBIC EXERCISE IN ATHLETES

NCT07445269 | Enrolling By Invitation

• 1 other identifier: 2025-39
• Study Type: interventional
• Target: 28
• Locations: 1 country
• Sites: 1

Brief Summary

Inspiratory muscle warm-up (IMW) is a specific pre-exercise breathing intervention designed to prepare the respiratory muscles before physical activity and potentially enhance exercise performance. Previous research suggests that IMW may acutely improve inspiratory muscle function; however, the duration of these effects during exercise and their responses under different exercise intensities remain unclear. Furthermore, placebo-controlled comparisons are limited in the current literature. The purpose of this study is to investigate the acute effects of inspiratory muscle warm-up on inspiratory muscle strength during aerobic and anaerobic exercise in trained athletes. The study will compare three experimental conditions: a standardized inspiratory muscle warm-up protocol, a placebo breathing warm-up, and a control condition without respiratory warm-up. In this repeated-measures interventional study, trained athletes aged 14-30 years will complete three experimental sessions in randomized order. The active intervention consists of inspiratory muscle warm-up performed at 40% of maximal inspiratory pressure (MIP). The placebo condition includes a low-resistance breathing protocol designed to mimic the intervention without providing a meaningful training stimulus. The control condition involves exercise performed without respiratory warm-up. Participants will perform treadmill exercise at intensity levels representing aerobic and anaerobic workloads, defined according to percentage of maximal heart rate. Inspiratory muscle strength (MIP) will be assessed at baseline, immediately after the warm-up protocols, and periodically during exercise to evaluate time-dependent changes. The primary objective is to determine how long the acute increase in inspiratory muscle strength is maintained during exercise and to compare responses between aerobic and anaerobic athletes across the three conditions. The findings may provide evidence-based guidance for integrating respiratory muscle warm-up strategies into sport-specific preparation routines.

Conditions

Healthy Participants

Keywords

Inspiratory Muscle Warm-Up; Inspiratory Muscle Strength; Maximal Inspiratory Pressure; Respiratory Muscle Performance; Aerobic Exercise; Anaerobic Exercise

Outcome Measures

Primary Outcomes (1)

• Time to Decline in Maximal Inspiratory Pressure (MIP) During Exercise

  Time (minutes) until maximal inspiratory pressure (MIP) decreases below baseline or post-warm-up levels during aerobic and anaerobic exercise following inspiratory muscle warm-up, placebo breathing warm-up, or control conditions.

  From exercise onset until the time of MIP decline during a single acute exercise testing session (up to 30 minutes).

Secondary Outcomes (2)

• Acute Change in Maximal Inspiratory Pressure After Warm-Up

  From exercise onset until MIP declines below baseline or post-warm-up values, assessed at minutes 2, 4, 6, 8, and 10, then at minutes 14, 18, 22, 26, and 30 (up to 30 minutes).

• Repeated MIP Measurements During Exercise

  Every 2 minutes during exercise.

Study Arms (3)

Inspiratory Muscle Warm-Up (40% MIP)

EXPERIMENTAL

Participants perform a standardized inspiratory muscle warm-up using a breathing resistance device set at 40% of maximal inspiratory pressure (MIP) prior to exercise testing. The protocol consists of resisted inspiratory efforts designed to acutely activate the respiratory muscles before aerobic or anaerobic exercise.

Behavioral: Inspiratory Muscle Warm-Up (40% MIP)

Placebo Breathing Warm-Up (15% MIP)

PLACEBO COMPARATOR

Participants perform a placebo breathing warm-up using the same device and procedures as the active intervention, but with resistance set at 15% of maximal inspiratory pressure (MIP). This low-resistance protocol is intended to mimic the intervention while minimizing meaningful physiological loading.

Behavioral: Placebo Breathing Warm-Up (15% MIP)

Control (No Respiratory Warm-Up)

NO INTERVENTION

Participants complete the exercise protocol without any inspiratory muscle warm-up prior to testing.

Interventions

Inspiratory Muscle Warm-Up (40% MIP) BEHAVIORAL

A standardized inspiratory muscle warm-up performed using a breathing resistance device set at 40% of maximal inspiratory pressure (MIP). Participants perform resisted inspiratory efforts prior to exercise to acutely activate respiratory muscles.

Inspiratory Muscle Warm-Up (40% MIP)

Placebo Breathing Warm-Up (15% MIP) BEHAVIORAL

A sham breathing warm-up performed using the same device and breathing pattern as the active intervention but with resistance set at 15% of maximal inspiratory pressure (MIP), intended to minimize physiological loading while maintaining procedural similarity.

Placebo Breathing Warm-Up (15% MIP)

Eligibility Criteria

• Age: 14 Years - 30 Years
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Child (0-17), Adult (18-64)

You may qualify if:

• Age between 14 and 30 years.
• Regular participation in organized sports training for at least 4 years.
• Engaged in predominantly aerobic or anaerobic sports disciplines.
• Training frequency of at least 3 sessions per week.
• No known cardiopulmonary disease affecting respiratory function.
• Ability to safely perform maximal effort treadmill exercise.
• No respiratory illness within the last 12 weeks.
• Willingness to comply with study procedures.
• Provision of written informed consent (and parental consent for minors where applicable).

You may not qualify if:

• History of asthma, chronic obstructive pulmonary disease (COPD), or other respiratory disorders.
• Age below 14 years or above 30 years.
• Orthopedic injury or condition limiting running ability.
• Participation in inspiratory muscle training within the last 12 months.
• Use of medications affecting respiratory or cardiovascular function.
• Active smoking.
• Failure to provide informed consent.

Sponsors & Collaborators

• Hitit University: lead

Study Sites (1)

Hitit University Faculty of Sport Sciences, Exercise Physiology Laboratory

Çorum, 19030, Turkey (Türkiye)

Location

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: QUADRUPLE
• Who Masked: PARTICIPANT, CARE PROVIDER, INVESTIGATOR, OUTCOMES ASSESSOR
• Masking Details: Participants and study staff are blinded to whether the breathing warm-up is performed at 40% MIP (active IMW) or as a placebo/sham protocol. Warm-up loads are pre-set by an independent staff member not involved in testing, and conditions are labeled with neutral codes (e.g., A/B/C). The intervention administrator and outcome assessor record and analyze outcomes using coded conditions. Unblinding occurs only after data collection is completed. (If a no-warm-up control session is included, it is described separately and may not be fully blind unless a sham breathing routine is used.)
• Purpose: BASIC SCIENCE
• Intervention Model: CROSSOVER
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Assistant Professor

Model Details: Participants will complete three conditions (inspiratory muscle warm-up, placebo breathing warm-up, and control with no respiratory warm-up) in a randomized crossover design. All participants will undergo each condition in separate sessions, with the order counterbalanced and sessions separated by adequate washout periods to minimize carryover effects. Inspiratory muscle strength will be assessed repeatedly within each session to characterize the time course of acute responses during aerobic and anaerobic exercise workloads.

Study Record Dates

• First Submitted: February 18, 2026
• First Posted: March 3, 2026
• Study Start: February 25, 2026
• Primary Completion: March 25, 2026
• Study Completion: March 30, 2026
• Last Updated: March 3, 2026

Record last verified: 2026-02

Data Sharing

• IPD Sharing: Will share
• Shared Documents: STUDY PROTOCOL, SAP, ANALYTIC CODE
• Time Frame: De-identified individual participant data will be available beginning 6 months after publication of the primary results and will remain accessible for up to 5 years, subject to reasonable request and ethical approval requirements.
• Access Criteria: De-identified individual participant data and supporting documents will be available to qualified researchers upon reasonable request. Researchers must submit a proposal outlining the research objectives, analysis plan, and intended use of the data. Requests will be reviewed by the principal investigator to ensure scientific validity, ethical compliance, and alignment with the original informed consent and institutional policies. Data sharing will require the signing of a data use agreement, and access will be provided for non-commercial scientific research purposes only. Data will be shared in anonymized form through secure electronic transfer.

Locations

TU (1)