Improving the Use of Lifting Velocity to Predict Repetitions to Failure: A Systematic Review

Area of Science:

• Sports Science
• Exercise Physiology
• Biomechanics

Background:

• Velocity-based training estimates repetitions to failure (RTF) using velocity.
• The RTF-velocity relationship's fundamental characteristics require systematic review.

Purpose of the Study:

• Determine the RTF-velocity relationship's properties: goodness of fit, reliability, and accuracy.
• Provide guidance on methodological factors influencing RTF prediction accuracy.

Main Methods:

• Systematic review of PubMed, SPORTDiscus, and Scopus databases.
• Included studies used multi-joint exercises, at least two sets to failure with varying loads, and recorded velocity and RTF.

Main Results:

• Robust goodness of fit and acceptable to high reliability for RTF-velocity relationships (1-15 RTF).
• Acceptable RTF prediction accuracy in fatigue-free conditions; accuracy compromised when fatigued, except for highly experienced athletes.
• Modeling procedure (multiple- vs. 2-point) impacted accuracy.

Conclusions:

• RTF-velocity relationship properties are consistent across exercise types, equipment, and rest periods (5-10 min).
• Individualized RTF-velocity relationships can be built using linear regression.
• Training experience is critical for improving RTF prediction accuracy.