Maternal awareness of young children’s physical activity: levels and cross-sectional correlates of overestimation

Physical activity plays an important role in the maintenance of health, with active children tending to have decreased adiposity [1, 2], fewer cardiovascular disease risk factors [3] and improved bone health [4] compared to their less active peers. Physical activity in preschool children may be particularly important as it has been associated with improved gross motor control [5] and aids the development of basic movement patterns that form the foundation of a wide range of movements later in life [6].

Levels of physical activity are known to decrease from late childhood into adolescence [7, 8]. Recently developed recommendations for preschoolers in a number of countries advocate 180 minutes of activity per day at any intensity [9–11], with previous guidelines suggesting engagement in 60 minutes of moderate-to-vigorous physical activity (MVPA) each day [6]. Studies have provided wide-ranging estimates as to how active three- to five-year-old children are: most suggest children engage in little MVPA [12–14] and that the new guidelines of 180 minutes may also to be difficult for children to meet [13]. As more favourable health outcomes have been related to physical activity of higher intensity in preschool aged children [15, 16] the importance of activity intensity for the youngest age groups is still under debate.

Interventions to increase levels of physical activity in young children may be beneficial, and although a growing number have been developed to increase physical activity in preschool children, outcomes have been mixed [17, 18]. The underlying reasons for variable intervention effects remain unclear, but both children’s and parents’ (lack of) awareness of physical activity levels may be an important determinant. Awareness of behaviour may be particularly relevant for complex, often habitual, health behaviours like physical activity [19]. Should people be unclear where the threshold lies between healthy and unhealthy behaviours [20], they may deem their own, or their child’s behaviour, to be healthier than it is. For example, adults who tend to overestimate their personal activity levels have been shown to have a lower BMI and better perceived health [20–22] compared to those who are realistic about their low levels of activity. These adults are unlikely to perceive a need for behaviour change and may therefore be less inclined to increase their low physical activity levels.

Parents have considerable influence over their children’s behaviours. The effect of factors such as positive role modelling, providing instrumental and social support, and parental participation on children’s activity levels have been frequently studied in preschool-aged children [23, 24]. Several studies conducted in school-aged children suggest nearly 80% of parents of inactive children perceived their child to be sufficiently active [25, 26], and that lack of awareness of inactivity is higher in parents than it is in children [25]. This may prevent parents engaging in interventions to modify their children’s behaviour [27], with few intervention studies currently taking parental awareness into account [28]. Further, parental awareness of their child’s behaviour may be particularly important in preschool-aged children given their young age and own lack of self-awareness [29].

This study aims to assess maternal awareness of physical activity levels in a population-based sample of four-year-old British children and determine biological, behavioural and psychological correlates of maternal overestimation. This will help establish whether similar associations as previously reported for older children are observed and identify correlates potential targets for future intervention.

The Southampton Women’s Survey is a population-based prospective cohort study based in Southampton, UK. Details of the cohort have been published previously [30]. The study was designed to assess maternal diet and lifestyle before and during pregnancy, with any subsequent live births followed to examine how children’s pre-natal development interacts with their postnatal growth, and how both may affect their risk factors for a range of future chronic diseases [30]. Parents of all participating children gave full and informed written consent. The Southampton and South West Hampshire Local Research Ethics Committee granted ethical approval for the study.

At age four, a subsample of 730 children participated in a secondary study to investigate potential correlates of physical activity. At this four-year-old visit, conducted between March 2006 and June 2009, objective measurement of physical activity was undertaken (n = 594) and a questionnaire was completed by the child’s mother (n = 569). This questionnaire has been validated in a subset of the cohort [31] with the specific measures used in analyses described below.

Fifty-nine per cent of parents accurately reported their child’s level of physical activity (55.0% realistically active; 4.2% realistically inactive). Of the 40.8% of inactive children, 89.7% of parents (36.6% of all parents) thought that their children were active. A number of parents with active children (7.1%; 4.2% of all parents) deemed their child to be inactive. Interestingly, regardless of children’s actual activity levels, parents who perceived their children to be inactive were less likely to report that their child was outgoing or enjoyed physical activity, or that physical activity was important. They were also more likely to report children showed a lack of interest in physical activity or lacked skills to be physically active.

This study assessed maternal awareness of preschool children’s physical activity and investigated correlates of overestimation in a population-based sample of four-year-old British children. Just over 40% of children did not accumulate 60 minutes per day of MVPA, the physical activity guideline for children at the time [6, 39]. However, a large proportion (~90%) of these children’s mothers perceived their child to be active. These findings suggest that mothers of inactive children do not, in general, perceive their child as such. If parents are unaware that their children are inactive, they may be less inclined to encourage physical activity or participate in interventions to promote it. When compared with mothers who accurately perceive their child as active, mothers were more likely to overestimate physical activity levels if their child attended nursery full time and if they perceived that their child on occasion lacked the necessary skills to participate in activities. In addition, mothers of children without older siblings were more likely to overestimate their child’s physical activity level.

The proportion of mothers in this study who overestimated their four-year-old’s activity level (~90%) was slightly greater than that previously reported in parents of 9 and 10 year-old children (~80%) [25, 26]. Mothers here also overestimated their child’s activity levels to a greater extent than adults have for their own activity [21, 22, 49]. It is possible that mothers overestimated activity levels here due to social desirability bias or because they were asked if they thought that their child was active, not whether their child engaged in 60 minutes of activity each day. This is a limitation of this study, but that two previous studies found similar levels of overestimation in parents of older children regardless of whether an average [25] or daily measure [26] of activity and parental perception was used, provides confidence in the validity of the findings presented here. Further, given that adults have been found to overestimate their own activity levels [21, 22, 49], and that only a moderate correlation exists between parental proxy reports and objectively measured physical activity [50], it is conceivable that many parents may not be aware of their child’s low level of physical activity.

Nursery attendance was independently associated with maternal overestimation: mothers were more likely to overestimate activity levels if their child attended nursery or preschool full time. Children now spend increasing amounts of time in preschool or nursery education, with studies showing that children in these settings are sedentary for a large proportion of the time [12]. It is plausible that mothers may hold unrealistic expectations or be over-optimistic about their child’s activity levels when they spend prolonged periods away from their child. An increased understanding of how physical activity levels differ according to whether a child is in a child-care setting, and how time spent at preschool is associated with physical activity levels would help to understand this observation and define intervention targets.

Mothers with one or more older child at home were less likely to overestimate their four-year old’s activity level. It is possible that having siblings older than the sample children provide mothers with a reference point on which to base their assessment of their four-year-old’s activity. However, it is difficult to disentangle this from the possibility that children with older siblings may be more active, as shown previously in older children [51, 52]. The association found between maternal perception that their child on occasion lacks the necessary skills to be physically active and overestimation is also interesting. Although this may be a chance finding, adults who overestimate their activity levels have previously been shown to have similar scores on psychological factors as those who are realistic [21]. Therefore mothers who acknowledge that their child on occasion lacks the skills required to be physically active may still believe that this does not affect their child’s overall level of activity, leading to its overestimation.

We did not find an association between child’s BMI z-score and maternal overestimation of activity. The absence of an association between BMI and overestimation in these analyses is in line with previous research, as we only compared inactive and active children of mothers who considered their child to be active. Previous awareness literature has predominantly compared over-estimators with those accurately reporting their own, or their child’s, inactivity. These studies consistently show that those with a (child with a) more favourable body composition tend to overestimate activity levels [21, 22, 25]. This association is hypothesized to occur because over-estimators assume a favourable body composition is indicative of sufficient physical activity. As there is no clear evidence of the association between physical activity and BMI (z-score) in preschool children [23], it is plausible that weight may be less salient to mothers when considering their child’s activity levels at this age. The percentage of overweight (8.6%) and obese (3.2%) children in this sample was lower than the English average (13% and 9.6% respectively) [53], but as mothers were not asked their perception of their child’s BMI, it is not possible to determine whether this was the case here.

A clear understanding of the influence parents have on their children's physical activity behaviour is required for the development of effective family-based interventions to promote physical activity in preschool children [54]. Given the majority of mothers of inactive children were unaware of their child’s inactivity, they may be less likely to encourage their child to engage in activity. As younger children do not possess the ability to adequately monitor their own behaviour [29], they must rely instead on parental proxy monitoring. It is interesting that regardless of activity level, mothers who deemed their child to be active held differing perceptions about a child’s general and activity behaviour from mothers who did not. Although far fewer mothers fell into the latter category, data presented here suggest that factors such as child temperament and mothers’ own perceptions about activity will also influence awareness. Improving this activity awareness may therefore be facilitated by use of monitors such as pedometers, whilst at the same time encouraging greater physical activity in children [55]. Use of pedometers in preschool children is feasible, with moderate correlations reported with accelerometry and direct observation to measure activity [50]. However, research is required to determine how different levels of parental awareness affect intervention success and whether monitoring evokes a positive change in preschool children’s behaviour. Nonetheless, maternal or parental awareness may be important to consider when trying to increase levels of physical activity in younger children.

A large proportion of mothers of inactive preschool children inaccurately perceive their child to be active. Promoting awareness of activity levels in mothers of children who spend large amounts of time at nursery school, who perceive their child on occasion lacks physical activity skills, or who do not have older siblings may be particularly important. These children may require more parental input to promote behaviour change and increase their activity levels. However, further research is also needed to investigate the effect of changes in awareness on behaviour change.