Predicting the Intensity for Performing Supramaximal Incline Treadmill Interval Training in Distance Runners

Area of Science:

• Exercise Physiology
• Sports Science
• Running Performance

Background:

• Supramaximal interval training (SMIT) is effective for distance runners.
• Incline treadmill training (INC) is a form of SMIT, but specific intensity guidelines for 30-second bouts are lacking.
• This study addresses the gap in prescribing SMIT using incline protocols.

Purpose of the Study:

• To determine the time-to-exhaustion (Tmax) and test-retest reliability of supramaximal incline treadmill training (INC) intensities.
• To establish the percentage of maximal oxygen consumption velocity (%Vmax) associated with a 30-second INC effort.
• To provide evidence-based recommendations for prescribing 30-second SMIT on an incline.

Main Methods:

• Twelve distance runners completed Tmax trials at various supramaximal intensities (110-130% Vmax) on a 5% grade, and at 140% Vmax on a 1% grade.
• Two trials were conducted at each intensity to assess reliability.
• Bivariate analysis was used to determine the %Vmax for a 30-second effort.

Main Results:

• All tested INC conditions demonstrated good test-retest reliability for Tmax.
• Tmax at 110% Vmax was significantly different from most other intensities.
• No significant difference in Tmax was found between 120%, 125%, 130%, and 140% Vmax conditions.

Conclusions:

• Supramaximal incline treadmill training intensities are reliable for eliciting Tmax.
• Running at 125% Vmax on a 5% grade reliably corresponds to a 30-second maximal effort.
• This finding offers a practical guideline for prescribing 30-second supramaximal interval training on an incline for distance runners.