Effects of Developmental Gymnastics Exercise Program on Preschoolers’ Motor Skills: A Randomised Controlled Trial

Background/Objectives: The developmental gymnastics (DG) exercise programme is a specialised form of gymnastics that focuses on the physical, cognitive, and motor development of individuals, particularly children. This 36-week study aimed to investigate the effect of DG on the gross motor skills (GMS) of preschoolers. Methods: This randomised controlled trial included 300 preschool children (5.1 ± 0.83 years), of whom 220 completed the 36-week programme (EG = 99, CG = 121). The children were randomly assigned to either an experimental group or a control group following standard physical activities. Attrition was mainly due to illness or attendance below 80%. Analyses were adjusted for age and BMI to control for confounding variables. Children in the CG participated in three organised extracurricular physical activities per week. In contrast, those in the EG engaged in 60 min of the designated exercise programme twice a week. We employed the Test of Gross Motor Development-2 (TGMD-2) to evaluate gross motor skills (GMS). Results: The mixed ANCOVA models revealed that EG showed greater improvement in all locomotor skills tests compared with the CG, with mean differences in TGMD-2 total scores of +3.28 points (p = 0.0002, partial η2 = 0.24). Effect sizes ranged from small to large (partial η2 = 0.05–0.19; Cohen’s d = 0.6–1.4), indicating meaningful practical improvements in gross motor competence. In the combined sample, both groups demonstrated similar improvements in all tests of object control skills. However, gender-specific differences were observed in the improvement of underhand roll, stationary dribble performance, and the total score of object control skills. Girls in the CG showed more improvement in underhand roll performance than girls in the EG. In contrast, boys in the EG demonstrated greater improvements in stationary dribble performance (4%) and the total score for object control skills (3%) compared to boys in the CG. Conclusions: The results of this study indicate that the nine-month DG programme was associated with significant improvements in GMS in preschool children. These findings highlight the value of structured gymnastics as a sustainable component of preschool curricula. Trial Registration Number: NCT06315036.