Analysis of upper limb propulsion in young swimmers in front-crawl through Statistical Parametric Mapping

Area of Science:

• Sports Science
• Biomechanics
• Swimming Performance Analysis

Background:

• Understanding upper limb propulsion is crucial for optimizing swimming technique.
• Previous analyses often relied on discrete measurements, potentially missing nuanced temporal changes.
• The dominant and non-dominant arm's contribution to propulsion requires detailed investigation in young athletes.

Purpose of the Study:

• To analyze the within-subject effect of dominant and non-dominant upper limb propulsion during consecutive arm-pulls.
• To compare upper limb propulsion between dominant and non-dominant sides in young swimmers.
• To evaluate the efficacy of discrete versus continuous (Statistical Parametric Mapping - SPM) analysis methods.

Main Methods:

• Seventeen elite young male swimmers (16.02 ± 0.61 years) performed a 25-m maximal front-crawl trial.
• Kinematic and propulsion variables were recorded, with analysis using discrete (average) and continuous (SPM) methods.
• Statistical analysis focused on within-subject effects of time (consecutive pulls) and side (dominant vs. non-dominant).

Main Results:

• Swimming velocity significantly decreased over the trial.
• A significant interaction between time and side was found; only the dominant arm showed a significant time effect (difference between first and third pulls).
• SPM analysis pinpointed the 'time' effect between 34-42% and differences between first/third pulls between 32-43% of the arm-pull cycle, with no significant side effect.

Conclusions:

• Propulsion diminishes across consecutive arm-pulls, especially in the dominant limb, over time.
• Statistical Parametric Mapping (SPM) offers more sensitive and precise insights into swimming propulsion dynamics than discrete analysis.
• Findings enable coaches to develop targeted training drills focusing on specific phases of the arm-pull for performance enhancement.