ROC Generated Thresholds for Field-Assessed Aerobic Fitness Related to Body Size and Cardiometabolic Risk in Schoolchildren

Abstract

Objectives1. to investigate whether 20 m multi-stage shuttle run performance (20mSRT), an indirect measure of aerobic fitness, could discriminate between healthy and overweight status in 9–10.9 yr old schoolchildren using Receiver Operating Characteristic (ROC) analysis; 2. Investigate if cardiometabolic risk differed by aerobic fitness group by applying the ROC cut point to a second, cross-sectional cohort.DesignAnalysis of cross-sectional data.Participants16,619 9–10.9 year old participants from SportsLinx project and 300 11–13.9 year old participants from the Welsh Schools Health and Fitness Study.Outcome MeasuresSportsLinx; 20mSRT, body mass index (BMI), waist circumference, subscapular and superilliac skinfold thicknesses. Welsh Schools Health and Fitness Study; 20mSRT performance, waist circumference, and clustered cardiometabolic risk.AnalysesThree ROC curve analyses were completed, each using 20mSRT performance with ROC curve 1 related to BMI, curve 2 was related to waist circumference and 3 was related to skinfolds (estimated % body fat). These were repeated for both girls and boys. The mean of the three aerobic fitness thresholds was retained for analysis. The thresholds were subsequently applied to clustered cardiometabolic risk data from the Welsh Schools study to assess whether risk differed by aerobic fitness group.ResultsThe diagnostic accuracy of the ROC generated thresholds was higher than would be expected by chance (all models AUC >0.7). The mean thresholds were 33 and 25 shuttles for boys and girls respectively. Participants classified as ‘fit’ had significantly lower cardiometabolic risk scores in comparison to those classed as unfit (p<0.001).ConclusionThe use of the ROC generated cut points by health professionals, teachers and coaches may provide the opportunity to apply population level ‘risk identification and stratification’ processes and plan for “at-risk” children to be referred onto intervention services.

Cardiorespiratory fitness and ideal cardiovascular health in European adolescents

“…Interestingly, the observed cut-off levels for cardiorespiratory fitness obtained in adolescents participating in the HELENA study are similar to those published previously by other studies conducted in past generations of children and adolescents from the USA9 and different European countries8 10 11 12 13 with diverse environmental, cultural and social factors. Of note is that previous studies used less comprehensive health indices than the one used in the present study and did not use behaviour-related components.…”

“…Moreover, they showed that boys who met the fitness levels were between four and five times more likely to have a low CVD risk compared with those who did not meet the standards. Comparable results were found (i) in 4500 children and adolescents from Denmark, Estonia, Norway and Portugal, who were tested as part of the European Youth Heart Study (EYHS);10 (ii) in 16 619 English children from the SportsLinx Project11 and (iii) in 450 Portuguese adolescents 13. All the aforementioned studies calculated mathematically the cardiorespiratory fitness levels associated with a more favourable cardiovascular profile, which turned out to be similar to the health-related cardiorespiratory fitness thresholds suggested by worldwide recognised organisations such as the European Group of Pediatric Work Physiology5 or the Cooper Institute for Aerobics Research6 7 (table 3).…”

A Preliminary Study of Physical Fitness in 8- to 10-Year-Old Primary School Children From North East England in Comparison With National and International Data

“…When our data were compared to European (IDEFICS) and the East of England Healthy Hearts Study reference data (14,49) using z scores, there were no meaningful differences in physical fitness parameters between the children in our study and the age-and sexmatched reference populations (z scores shown in Table 1). Table 3 details study level and participant characteristics from our investigation and other contemporary English data sets where data were available (1,6,10,11,35,37,40). As publicly available raw data were not available for English data other than from East of England Healthy Hearts Study, further statistical comparisons of physical fitness parameters via z scores were not possible.…”

“…When aerobic fitness is defined as mass-related VO 2peak, there appears to very little historic change in young people's aerobic fitness (4). Conversely, when the term is operationalized as maximal field-based endurance running performance (eg, 20-m shuttle run test [20mSRT] performance), the global picture is one of decreasing levels for several decades (4,6,33,41,44,46,50). This public health problem is of particular concern in England, with data from some regions indicating that aerobic fitness performance specifically is declining by around 8% per decade (36,41)-twice the rate observed in other developed nations (45).…”

“…Hearts Study (11,35,50) and the Chelmsford Children's Fitness and Activity Survey (10,37), and in the South East by the Camden Active Spaces project (1). The North West is well represented by the repeat cross-sectional study SportsLinx (6,40,41). To date, however, there are no published data on children from the North East of England, who have some of the highest obesity levels in the country (25) and often reside in areas with high levels of deprivation (15).…”