A study with families in Southampton found 47 percent of six-year-olds did not meet the recommended daily guidelines for physical activity.
The study was carried out pre-pandemic by researchers at the universities of Southampton and Cambridge. All families who took part were involved in the ongoing Southampton Women’s Survey.
Children who are active are more likely to be active adults, reducing their risk of obesity and many lifestyle-related diseases later in life. They need to be active for their muscles and bones to develop properly. Being active also improves their ability to concentrate, boosts their mood and leads to better educational performance at school.
Yet the results from this study, published in the Journal of Physical Activity & Health, suggest almost half of children are not active enough.
Why do children need to be active?
Physical activity is beneficial for children’s physical and mental health. They need to do a mix of aerobic exercise, which improves fitness, as well as exercises to strengthen their muscles and bones.
Current UK guidelines recommend that children aged 5 to 18 years do, on average, an hour of moderate-to-vigorous physical activity each day. This could include playing in the playground, physical education (PE) lessons or after school sports clubs.
Moderate intensity activities raise your heart rate, and makes you breathe faster and feel warmer. One way to tell if you're working at a moderate intensity level is if you can still talk, but not sing.
It is also recommended that extended periods of sedentary behaviour, such as sitting watching TV or screen use, are kept to a minimum.
Investigating young children’s activity
Researchers from the MRC Lifecourse Epidemiology Centre at the University of Southampton and the MRC Epidemiology Unit at the University of Cambridge set out to investigate how much activity children do in their transition from preschool to primary school.
They gave 712 six-year-olds from the Southampton Women’s Survey Actiheart accelerometers to wear. These attach to the chest, and measure heart rate and movement. The children wore them continually for an average of six days.
Just over half of the children (53%) met the current UK recommended guidelines. Boys were more likely to reach the target than girls (63% of boys vs 42% of girls).
On average, the six-year-olds did just over an hour (65 minutes) of moderate-to-vigorous physical activity each day. They did over 7.5 hours (457 minutes) of low-level physical activity, and were sedentary for more than five hours (316 minutes).
When the researchers analysed activity levels by time of day, they found that girls engaged in less moderate-to-vigorous physical activity during the school day.
Professor Keith Godfrey, from the NIHR Southampton Biomedical Research Centre, said:
“These analyses indicate that new initiatives to promote physical activity must consider the lower activity levels in girls and at weekends. The time when children transition into formal schooling is an important opportunity to ensure a much higher proportion achieve recommended levels of activity.”
Dr Esther van Sluijs, from the MRC Epidemiology Unit at Cambridge, said: “Using accelerometers, we were able to get a much better idea of how active children were and we found that just over a half of six-year-olds were getting the recommended amount of physical activity. But this means that almost half of British children in this age group are not regularly active, which we know is important for their wellbeing and their performance at school.”
Comparing against activity at age four
For some children, the researchers could look at back at data from when they were age four.
Compared to age four, the children were more sedentary (on average, around 30 minutes more per day). But they also did an extra seven minutes of moderate-to-vigorous physical activity.
Dr Kathryn Hesketh from the MRC Epidemiology Unit at Cambridge added: “This is something of a double-edged sword: children appear to do more moderate-to-vigorous physical activity when they start formal schooling, which is really positive, but they also spend more time sedentary.
“This may in part be because of the structure of the school day, so we may want to look at ways to reduce sedentary time when children are younger, to prevent that behaviour becoming habitual.”
This analysis was based on data collected up to 2012. Yet questionnaire findings from national surveys suggests children's activity levels has changed little up to 2020. During the COVID-19 pandemic were lower still. The work was largely supported by the Wellcome Trust and the Medical Research Council.