Tracking of physical fitness in elementary school children: The role of changes in body fat

Abstract

Objectives The aim of the present study was to examine the stability of physical fitness, and the interrelationships among intra‐individual changes in fitness and fatness among elementary school children. Methods A longitudinal study was conducted among 372 adolescents (196 boys) and followed up over 3 years (from childhood to adolescence). Physical fitness was estimated using three indicators: cardiorespiratory fitness (through a 9‐minute running test), flexibility (through a sit‐and‐reach test), and muscle resistance (through maximal abdominals in 1 minute). Body adiposity was obtained through triceps and subscapular skinfolds. Somatic maturation was assessed by the peak of height velocity. Kappa and Lin's tests of concordance as well as logistic regression analyses were conducted with P < 0.05 in STATA 15.1. Results Tracking of physical fitness from childhood to adolescence was moderate for both sexes [boys: kappa = 0.441 (P < 0.001); LCCC = 0.591 (P < 0.001). Girls: kappa = 0.335 (P < 0.001); LCCC = 0.534 (P < 0.001)]. A larger increment in body fat was associated with a higher likelihood to decrease a tertile in physical fitness among boys [OR: 4.17 (95% CI: 1.31‐13.22)] and with a lower likelihood to increase a tertile in physical fitness among both sexes [boys: OR = 0.25 (95% CI: 0.09‐0.67); girls: OR: 0.37 (95% CI: 0.15‐0.92)]. Conclusions Health‐related physical fitness has moderate tracking from childhood to adolescence. Increases in body adiposity from childhood to adolescence are associated with a reduction in physical fitness tertile.

Explosive Strength Modeling in Children: Trends According to Growth and Prediction Equation

“…The biological maturation (MO) was estimated through the somatic maturation method proposed by Werneck et al [27].…”

“…Children performed an SBJ as per the field test guidelines. The biological maturation (MO) was estimated using the somatic maturation method proposed by Werneck et al [27]. Then, the age of PHV was determined by subtracting the MO from the chronological age.…”

Factors Associated with Physical Fitness among Overweight and Non-Overweight Austrian Secondary School Students

“…Ortega et al [14] found in a prospective study of about 600 normal-weight children over a duration of six years that improvements in fitness from childhood to adolescence are related with a reduced risk of becoming overweight or obese in adolescence. Werneck et al [15] recently reported convincing association between increases in body adiposity from childhood to adolescence and the reduction in physical fitness in a three-year longitudinal study including about 370 children. In addition, Greier and Drenowatz [16] showed in a four-year longitudinal study of more than 200 Austrian middle school students a bidirectional, inverse association between body weight and physical fitness.…”

Interrelationship between muscle fitness in childhood and bone mineral density in adulthood: mediation analysis of muscle fitness in adulthood

“…This prospective study was initially designed to examine growth, maturation and physical fitness in schoolchildren aged 7 to 10 years recruited from a private school in Londrina (Paraná, Brazil), with a mixed longitudinal design with four birth cohorts (1992, 1993, 1994, 1995) followed annually from 2002 to 2006 (initial moment research approved by ethics committee of Campinas State process CEP N 249/2002, July 16, 2002, and longitudinal data by ethics committee of Londrina State University process CEP N 024/03, April 01, 2003). Criteria of sampling were an α of 95%, a statistical power of 80%, and an error of 5% as previously described [ 26 ]. Parents or legal guardians of 1052 children signed an informed consent, and participants were informed that their participation was voluntary.…”