Marla Gabriela Pulley-García

Introduction: Psychological factors can be important for the physical performance of developing female football players, but research is needed to assess their impact. Objective: To determine the effectiveness of a motivational psychological intervention strategy to improve physical performance in female U-15 football players from a football school in Zone 8 of Guayaquil, Ecuador. Method: Pre-experimental design with a single group and pretest-posttest measurements. Thirty football players participated. For the evaluation of the motivational climate, the PMCSQ-2 was used, while the YYIR1 and the Cooper Test were the instruments employed to assess physical performance. The intervention consisted of 12 sessions of 45 minutes over six weeks. The Shapiro-Wilk test was applied and then the Student's t-test for dependent samples. Results: The overall PMCSQ-2 score did not show statistically significant changes (t(29) = −1.37; p = 0.182; d = −0.250). On the contrary, statistically significant differences with large effect sizes were found for both the YYIR1 (t(29) = −16.08; p < 0.001; d = −2.936) and the Cooper Test (t(29) = −19.54; p < 0.001; d = −3.567). Discussion: Improvements are evident in the evaluated physical indicators, without significant changes in the overall motivational score. This divergence indicates that the physical response and the perception of the motivational climate do not always develop at the same pace. Conclusions: The intervention was associated with significant improvements in physical performance, which supports its application in youth women's football.