Cardiorespiratory fitness cut points to avoid cardiovascular disease risk in children and adolescents; what level of fitness should raise a red flag? A systematic review and meta-analysis.
BACKGROUND
Poor cardiorespiratory fitness is associated with cardiovascular disease risk factors.


OBJECTIVE
To perform a systematic review and meta-analysis of the relationship between poor cardiorespiratory fitness and cardiovascular disease risk in children and adolescents.


METHODS
Systematic literature search (1980 to 11 April 2015) for studies that determined a cardiorespiratory fitness cut point that predicted cardiovascular disease risk in children and adolescents.


RESULTS
We identified 7 studies that included 9280 children and adolescents (49% girls) aged 8-19 years from 14 countries. Cardiovascular disease risk was already present in boys (6-39%) and girls (6-86%). Boys with low fitness (<41.8 mL/kg/min) had a 5.7 times greater likelihood of having cardiovascular disease risk (95% CI 4.8 to 6.7). The comparable diagnostic OR for girls with low fitness (<34.6 mL/kg/min) was 3.6 (95% CI 3.0 to 4.3). The 95% confidence region of cardiorespiratory fitness associated with low cardiovascular disease risk ranges, 41.8-47.0 mL/kg/min in boys (eg, stages 6-8 for a boy aged 15 years) and 34.6-39.5 mL/kg/min in girls (eg, stages 3-5 for a girl aged 15 years). The cardiorespiratory fitness cut point to avoid cardiovascular disease risk ranged 41.8 mL/kg/min in boys and was 34.6 mL/kg/min in girls.


CONCLUSIONS
Fitness levels below 42 and 35 mL/kg/min for boys and girls, respectively, should raise a red flag. These translate to 6 and 3 stages on the shuttle run test for a boy and a girl, both aged 15 years, respectively. These cut points identify children and adolescents who may benefit from primary and secondary cardiovascular prevention programming.
PROmoting FITness and Health through Physical Activity Research Group (PROFITH), Department of Physical Education and Sports, Faculty of Sport Sciences, University of Granada, Granada, Spain.
Jonatan R
JR
Ruiz
Universidad de Castilla-La Mancha, Health and Social Research Center, Granada, Spain.
Ivan
I
Cavero-Redondo
PROmoting FITness and Health through Physical Activity Research Group (PROFITH), Department of Physical Education and Sports, Faculty of Sport Sciences, University of Granada, Granada, Spain.
Francisco B
FB
Ortega
Department of Kinesiology, Iowa State University, Ames, Iowa, USA.
Gregory J
GJ
Welk
Faculty of Teacher Education and Sport, Sogn og Fjordane University College, Sogndal, Norway.
Lars B
LB
Andersen
Universidad de Castilla-La Mancha, Health and Social Research Center, Granada, Spain.
Vicente
V
Martinez-Vizcaino
Adolescent; Aerobic fitness; Cardiovascular; Children; Exercise testing