Quantifying change of direction load using positional data from small-sided games in soccer

ABSTRACT

Rapid changes in velocity and direction place high mechanical loads on players, but are ignored in commonly used load indicators.

Purpose

Quantifying change of direction (COD) load through positional data from small-sided games (SSG) and assess its criterion and construct validity.

Methods

Elite male youth soccer players (n = 25, 16.8 ± 1.3 years) played three SSG (5v5, 5×4 min) with different field dimensions (small [40×30 m], medium [55×38 m], large [70×45 m]). Positional data of the players was obtained with a Local Position Measurement system. COD load (AU) was quantified based on the combination of velocity and change in heading direction. Additionally, total distance covered, running distance, acceleration count, deceleration count, and Rating of Perceived Exertion were measured. Criterion validity was assessed by correlating COD load and the load indicators. Construct validity was determined by testing the differences between the SSG field dimensions.

Results

Strong correlations were determined between COD load and total distance covered (r = 0.74, p < .01) and running distance (r = 0.84, p < .01). Middle and large field size resulted in highest COD load (p < .05).

Conclusion

These results suggest that the COD load measure shows sufficient criterion and construct validity.

KEYWORDS:

• Agility
• load
• small-sided games
• local positioning

Disclosure of interest

All authors have no conflict of interest and declare that the results of the study are presented clearly, honestly, and without fabrication, falsification, or inappropriate data manipulation.

Additional information

Funding

No funding is associated with this study.