Small-Sided Games vs. Running-Based High-Intensity Interval Training: An Exploratory Study of the Effects on Physical Performance and Internal Load in Under-11 Male Football Players.

BACKGROUND

This study aimed, in U11 male football players, (i) to investigate the effects of an 8-week running-based HIIT or SSGs program on aerobic fitness, neuromuscular performance and internal load, and (ii) to compare training-induced changes in performance variables between training modalities.

METHODS

Sixteen U11 football players were randomly assigned to either the SSGs group (4 vs. 4 format, 5 × 3 min with 1 min of rest between bouts) or the HIIT group (5 × 3 min of 15 s running at 100% peak velocity (Vpeak) alternating with 15 s of recovery, and 1 min of rest between sets). The intervention period lasted 8 weeks. Aerobic fitness (Yo-Yo Intermittent Recovery Level 1 Children's Test, YYIR1C), sprint time performance (10 m and 20 m sprints tests) and change-of-direction (COD) ability (Arrowhead Agility Test) were assessed before and after the intervention. Heart rate (HR) and rating of perceived exertion (RPE) were assessed as indices of internal load.

RESULTS

Both SSGs and running-based HIIT produced comparable improvements in YYIR1C distance, Vpeak (p < 0.05), with no significant change in the between-group difference. Neuromuscular gains occurred only after SSGs (p < 0.05), with similar 10 m sprint improvements between groups but superior 20 m gains for SSGs (p < 0.01). COD ability improved in both groups (p < 0.05), with broader enhancements following SSGs (p < 0.05). Finally, running-based HIIT elicited greater HRpeak and higher RPE than SSGs (p < 0.05) across most intervention weeks.

CONCLUSIONS

In U11 male football players, both SSGs and running-based HIIT effectively improved aerobic fitness and COD performance. However, SSGs may offer additional benefits for sprint development with lower perceived psychological stress.