Research

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The isoflow method, which measures inspiratory muscle endurance by maintaining a constant flow while subjects perform repeated maximum voluntary inspirations, provides a reproducible and accurate assessment of inspiratory muscle fatigue in healthy humans.

This paper describes a specialized laboratory method for testing breathing muscle endurance, not a home exercise. It shows that breathing muscles fatigue in a predictable, exponential manner when pushed to maximum effort at a constant airflow. For athletes or patients with lung issues, this test can accurately measure how well their diaphragm and accessory muscles hold up over time, identifying fatigue earlier than standard tests.

GoodSupportsHIGH confidence
In this study we describe a method for studying inspiratory muscle fatigue in humans that provides a picture of the gradual loss of inspiratory pressure as the muscles fatigue by repeated maximum voluntary efforts.
Brad J. Schöenfeld et al. · Strength and conditioning journal · 2013

Why this rating

Controlled study with 16 subjects, high reproducibility, and clear methodology, but small sample size.

Source

The Muscle Pump

Brad J. Schöenfeld et al. · Strength and conditioning journal · 2013

DOI 10.1519/ssc.0000000000000021

mechanism_only · n=16Cited 17×
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DOI resolved against Crossref · corpus check 2026-06-10

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