The study explores how different footwear conditions (barefoot, minimalist shoes, and standard running shoes) affect running impact loading among preschool-aged children. The authors evaluated 48 habitually shod preschool children aged 3 to 6 years, which were divided into four age groups (3-, 4-, 5-, and 6-year-olds).

The children participated in a running game while wearing each type of footwear, and their running was analyzed using 3D biomechanical methods. The authors evaluated the vertical ground reaction forces and vertical instantaneous loading rates during running, hypothesizing that younger children (3- and 4-year-olds) would experience higher impact loading in barefoot and minimalist shoes compared to standard running shoes.

Key findings include:

• Three-year-old children showed significantly lower vertical ground reaction force values when barefoot compared to when wearing minimalist shoes (3-7% stance) and standard running shoes (7-11% stance).
• The vertical instantaneous loading rate was also lower for 3-year-olds running barefoot compared to both shod conditions, indicating that barefoot running may reduce impact loading.
• No significant differences in impact loading were found for the older children (4- to 6-year-olds), suggesting that their running mechanics might adapt differently to various footwear conditions.

The study highlights that running in minimalist shoes does not replicate barefoot running for young children and may even lead to increased impact loading, particularly in 3-year-olds. The results indicate that careful consideration should be given to the use of minimalist footwear for young children, especially when they are running on hard surfaces.

The research calls for further studies to explore the longitudinal effects of different footwear on impact loading and the potential risks associated with running in minimalist shoes during early developmental stages. Overall, the findings contribute to understanding how footwear influences running mechanics in preschool-aged children, emphasizing the need for appropriate footwear choices to minimize injury risks 12 and 14.