A submaximal treadmill test to predict critical speed

Area of Science:

• Exercise Physiology
• Sports Science
• Biomechanical Analysis

Background:

• Critical speed (CS) is a key physiological marker for endurance performance.
• Accurate prediction of CS is crucial for effective training program design.
• Existing methods for CS determination can be time-consuming and resource-intensive.

Purpose of the Study:

• To evaluate the reliability and validity of a 10-minute submaximal treadmill test (T10) for predicting critical speed (CS).
• To establish T10 as a practical and accessible alternative for CS assessment.
• To compare T10-derived CS with CS determined from traditional field tests.

Main Methods:

• Forty-two runners underwent familiarization and two experimental trials (T10 test and retest).
• Reliability was assessed using coefficient of variation (CoV), limits of agreement (LoA), and intraclass correlation (ICC).
• Validity was determined by comparing T10 retest speed with CS from 1200m, 2400m, and 3600m track runs.

Main Results:

• High reliability was observed between T10 test and retest (CoV: 3.4%, ICC: 0.93).
• No significant difference in speed was found between T10 retest (3.86 ± 0.51 m/s) and field test (3.88 ± 0.55 m/s).
• A strong correlation (r = 0.93) existed between T10 retest and field test CS, with a low standard error of estimate (0.06 m/s).

Conclusions:

• The 10-minute submaximal treadmill test (T10) demonstrates excellent reliability and validity for predicting critical speed (CS).
• T10 offers a practical, accessible, and time-efficient method for estimating CS in runners.
• This test can be readily implemented in various training and assessment settings.