Determination of optimal shoe fitting for children tennis players: Effects of inner-shoe volume and upper stiffness

Influence of shoe torsional stiffness on foot and ankle biomechanics during tennis forehand strokes

Tennis shoe characteristics need to minimise the risk of athletes suffering ankle injuries and improve players' feet performance. This study aims to evaluate the influence of shoe torsional stiffness on running velocity, stance duration, ground reaction forces and ankle biomechanics during two different tennis forehand runs and strokes. Ten right-handed advanced male tennis players performed two specific tennis forehand runs and strokes at maximal effort (a shuttle run with a defensive open stance forehand - SRDF and a lateral jab run with an offensive open stance forehand - JROF) with four different pairs of tennis shoes with different torsional stiffness. A force platform measured ground reaction forces (GRF). A motion capture system recorded the 3D trajectories of markers located on players' anatomical landmarks. The minimum, maximum angle value, and range of motion were computed using inverse kinematics for each rotation axis of the right ankle. Normalised maximal ankle torques were also computed using inverse dynamics. Shoe torsional stiffness had no effect on running velocity, on stance duration and maximal values of GRF. Shoe torsional stiffness influenced forefoot inversion which was significantly higher for the most flexible shoes. For SRDF, the maximal ankle inversion angle was significantly and largely increased for the stiffest shoe. The stiffest shoe may put the ankle at a higher risk of lateral sprains during SRDF while it was not the case during JROF.

Impact of length and width of footwear on foot structure of preschool-aged children

Background

Due to the dynamics of developmental changes, the preschool age is of crucial importance for the later health and efficiency of the feet. The aim of this study was the analysis of the fitting of indoor footwear and its impact on the features of the foot structure in 6-year-old children.

Methods

The study group consisted of 100 children, including 50 girls and 50 boys at the age of 6 years. The applied device was the CQ-ST podoscope and the Clevermess. The data were analyzed based on Mann-Whitney U test, Chi-square test and regression analysis.

Results

About 60% of children wore correctly fitted shoes in terms of length and width. Multiple regression models with two variables explaining the variance of the Clarke's angle were statistically significant for girls (right foot: p < 0.001 and left foot: p = 0.009), and boys (right foot: p < 0.001 and left foot: p < 0.001). The influence of predictive variables on the values of the heel angle (γ) was statistically significant for girls (right foot: p < 0.001 and left foot: p < 0.001) and boys (right foot p < 0.001 and left foot: p < 0.001).

Conclusions

Both in the case of girls and boys, the frequency of using too long and too wide shoes was higher in relation to the frequency of using too short and too narrow shoes. The length and width of the shoes affected the length and width of the footwear both in girls and boys. The longer and wider the shoes, the lower the height of the arch. Longer shoes are accompanied by a greater transverse arch, and wider ones with a lower transverse arch of the foot.

Children should be seen and also heard: an explorative qualitative study into the influences on children's choice of footwear, their perception of comfort and the language they use to describe footwear experiences

BACKGROUND

Footwear has an essential role including protection of the feet, overall performance, foot health and potentially, supporting normal development of the foot. In addition to these physical aspects which may influence choice of footwear design, there are psychological influences on what a person chooses to wear. The concept of footwear 'comfort' spans physical and psychological perceptions of comfort in adults. However, there is little understanding of what influences children's footwear choices, how children perceive footwear comfort, or the language used to describe footwear experiences. Therefore, this study aimed to explore these three parameters as the first step to informing the development of a scale to measure footwear comfort in children.

METHODS

A pragmatic qualitative design with thematic analysis as an analytical approach was implemented. Passive observation and short interviews were carried out with 23 children (aged 1-12 years) at a footwear manufactures headquarters and store. Prompts included shoes being tried on and field-notes were taken relating to verbal and non-verbal communication. Field notes were coded then themes were identified, reviewed and named.

RESULTS

Overall, the children equated comfort to softness. However, influences on footwear choice were multidimensional including aesthetics, psychosocial influences, identified 'comfort' and 'discomfort' areas, practical issues and predictive concerns; all interacting with the age of the child.

CONCLUSIONS

For children, footwear comfort is a complex phenomenon having physical, cognitive, social and emotional developmental components. This can be seen in how the children perceive the 'feel' of the shoe and how the shoe is assessed in the context of how the shoe meets the child's physical and psychosocial developmental needs. In younger children footwear preference is related to idiosyncratic tastes in aesthetics, physical ability and comfort. As children age, societal influences begin to expand the social function of footwear denoting group membership, to include themes that transcend the functional and social function of footwear. The knowledge from this study can inform the development of age group specific tools to evaluate comfort.

Key concepts in children's footwear research: a scoping review focusing on therapeutic footwear

BACKGROUND

Reports suggest that children with mobility impairment represent a significant proportion of the population living with a disability. Footwear is considered to be the key extrinsic factor affecting children's gait and footwear modifications have been historically postulated to assist with locomotory difficulty. Although therapeutic footwear has been considered within the literature, there is a lack of consistency on terminology and paucity on the overall understanding. A scoping review was performed to chart the key concepts in children's footwear and to establish the range of studies that considered therapeutic footwear.

METHODS

A systematic search of MEDLINE, CINAHL, PubMed, SPORTdiscus, and Scopus electronic databases was performed using MeSH headings and free text terms in relation to children's footwear. All studies that used footwear as an intervention in children aged 9 months to 18 years with the outcome measures including design, fit, and the effects on development and health were included. Studies were charted by textual narrative synthesis into research groupings dependent on the topics discussed and the methods used in the studies.

RESULTS

The search yielded a total of 5006 articles with 287 of these articles meeting the inclusion criteria. Two overarching areas of research were identified; articles that discussed footwear design and those that discussed the effects of footwear. Eight further general groupings were charted and apportioned between the overarching areas and therapeutic footwear was charted into three subgroupings (corrective, accommodative and functional).

CONCLUSION

Children's footwear has become an increasing area of research in the past decade with a shift towards more empirical research, with most of the included articles examining biomechanical and anthropometric aspects. However, children's therapeutic footwear has not shared the same recent impetus with no focused review and limited research exploring its effects. Empirical research in this area is limited and there is ambiguity in the terminology used to describe therapeutic footwear. Based on the findings of this review the authors suggest the term children's therapeutic footwear be used as the standard definition for footwear that is designed specifically with the purpose to support or alleviate mobility impairment in childhood; with subgroupings of corrective, accommodative and functional dependent on the intended therapeutic role.