This is an excerpt from Life Span Motor Development by Kathleen Haywood & Nancy Getchell.
There is an old saying that “perception is reality”; in our context, this suggests there is a connection between what individuals perceive their motor capabilities are and how they actually move. In fact, perceived motor competence is an important source of achievement-related behaviors such as participation in physical activity (Ryan & Deci, 2000), as was discussed in chapter 12. Benefits of high perceived competence can include higher self-esteem and increased performance effort and engagement (Robinson, 2011). Recent findings suggest that a developmental relationship exists between actual and perceived motor competence (Barnett, Morgan, van Beurden, & Beard, 2008; De Meester et al., 2016; LeGear et al., 2012; Robinson, 2011).
During early childhood, children tend to inaccurately perceive their actual motor abilities, interpreting increased effort as higher levels of motor skill competence (Goodway & Rudisill, 1997; Harter & Pike, 1984; Gabbard, Caçola, & Cordova, 2009). At the same time, the association between perceived and actual motor competence tends to be positive, such that young children with higher perceived competence tend to have higher actual motor competence (Barnett et al., 2008). In 2010, Robinson tested 119 preschool children on the TGMD-2 (Ulrich, 2000) and the Pictorial Scale of Perceived Competence and Social Acceptance (Harter & Pike, 1984), then correlated the results. She found moderate positive relationships between the measures that were stronger for locomotor skills than object control skills as well as stronger for girls than boys. Other studies have found moderate positive correlations between these measures in young children—in particular, in object control skills—in countries such as Canada (LeGear et al., 2012), Denmark (Toftegaard-Stoeckel, Groenfeldt, & Andersen, 2010), and Australia (Barnett, Ridgers, & Salmon, 2015; Liong, Ridgers, & Barnett, 2015).
KEY POINT How young children perceive or comprehend their motor competence generally does not match their actual motor competence.
As children move into middle childhood, they improve in their ability to accurately perceive their actual motor competence (Harter, 1999). However, gender differences persist. In their study of 58 children between the ages of 8 and 10 years, Clark, Moran, Drury, Venetsanou, and Fernandes (2018) also had children perform the TGMD-2 and the Pictorial Scale of Perceived Movement Skill Competence for young children. They had three key findings. First, although there were no significant differences between boys and girls in actual motor skills, gender differences existed in their perceived motor skills, with boys perceiving higher motor competence than girls in both locomotor and object control skills. Second, girls perceived locomotor skills to be significantly lower than their actual locomotor skills. Finally, boys perceived their object control skills to be significantly higher than their actual object control skills. This mismatch by genders has been noted in other research as well (Masci et al., 2017).
As children become adolescents, it has been hypothesized that their perceptions should come in line with their actual movement abilities (Harter, 1999; Stodden et al., 2008). Interestingly, research has found several distinct patterns. De Meester et al. (2016) used the KörperkoordinationsTest für Kinder (KTK) to measure actual motor competence and used validated questionnaires to measure perceived motor competence (among other measures) in 215 adolescents (average age: 13.64 ± 0.58 years). Although actual and perceived motor competence were only moderately correlated, when the researchers performed a cluster analysis—a statistical test that groups similar variables into the same cluster—they found four distinct clusters. They classified the first group of subjects as “low - accurate” estimators; their low perceptions accurately reflected their low abilities. The next cluster consisted of adolescents described as “low overestimators.” Despite their actual motor abilities being lower than all other groups, they perceived their abilities to be much better, even better than the “average - accurate” estimators, who matched perceived and actual ability fairly well. The last group were average in terms of motor performance but overestimated their ability. Undoubtedly, the relationship between perceived and actual competence changes over time in a nonlinear fashion.
Since Stodden and colleagues published their paper in 2008, several studies have looked at the relationship between motor skill competency and physical activity, finding positive associations between the two that change developmentally (Barnett, Van Beurden, Morgan, Brooks, & Beard, 2009; Lopes, Santos, Pereira, & Lopes, 2012; see Holfelder & Schott  and Lubans, Morgan, Cliff, Barnett, & Okely  for systematic reviews). Researchers have hypothesized that perceived motor competence acts as a mediator between actual motor competence and physical activity (Barnett et al., 2008; De Meester et al., 2016; Stodden et al., 2008; see chapter 2). A mediator variable explains the relationship between two other variables. Stated simply, the relationship between individuals' actual motor competence and how physically active they are depends, in part, on how competent they perceive themselves to be (Barnett, Ridgers, & Salmon, 2015; Barnett, Lubans, Timpeiro, Salmon, & Ridgers, 2018; Bardid et al., 2016).
In a longitudinal study over 6 years, Barnett et al. (2008) found perceived competence mediated children's object control competence and self-reported physical activity during the adolescent years. In this study, 928 children were assessed for motor skill proficiency as part of a school-based physical activity intervention. Six years later, 276 participants completed assessments for perceived sports competence (Physical Self-Perception Profile), physical activity (Adolescent Physical Activity Recall Questionnaire), and cardiorespiratory fitness (multistage fitness test). These data were analyzed using structural equation modeling. The results found that perceived competence acted as a mediator between object control skill proficiency developed in early childhood and later fitness and physical activity during adolescence. In other words, object control skill proficiency as a child (regardless of gender) appears important in developing a positive perception of competence in sports and seems to increase physical activity and fitness outcomes as an adolescent. Within the literature, there is increasing support that perceived motor competence mediates the relationship between actual motor competence and physical activity, although more experimental and longitudinal studies need to be performed to confirm this (Robinson et al., 2015).