Low agreement between the fitnessgram criterion references for adolescents

OBJECTIVE: To analyze the association and agreement of fitnessgram reference criteria (RC) for cardiorespiratory fitness, body mass index (BMI) and strength in youth. METHODS: The study included 781 youth, 386 females, aged 10 to 18 years of Londrina-PR. It were performed cardiorespiratory fitness and muscular strength tests and was calculated body mass index. The association between the tests was analyzed using Poisson regression to obtain prevalence ratio (PR) and confidence intervals of 95%, while agreement of the reference criteria was tested by Kappa index. RESULTS: Significant associations were found between cardiorespiratory fitness and BMI (PR=1,49, 1,27-1,75), muscle strength and BMI (PR=1,55, 1,17-2,08), cardiorespiratory fitness and muscle strength (PR=1,81, 1,47-2,24). The agreement between reference criteria ranged from weak to fair, 48.8% (k=0.05, p=0.10) for cardiorespiratory fitness and BMI, 52.9% (k=0.09, p=0.001) for muscle strength and BMI and 38.4% (k=0.22, p<0.001) for cardiorespiratory fitness and muscle strength. CONCLUSIONS: Although RC for cardiorespiratory fitness, muscle strength and BMI are associated, the agreement between them ranged from weak to fair. To evaluate health related physical fitness it is suggest the execution of all tests, since each test has specific characteristics.

研究目的：分析针对青少年的心肺适能、体质指数（Body Mass Index, BMI）以及肌肉力量的健身健康测评（Fitnessgram）参考标准（Reference Criteria, RC）之间的关联与一致性。
研究方法：本研究纳入巴西巴拉那州隆德里纳市的781名青少年，其中女性386名，年龄介于10至18岁之间。研究人员开展了心肺适能与肌肉力量测试，并计算了受试者的体质指数。采用泊松回归分析各测试指标间的关联，以获取患病率比（Prevalence Ratio, PR）及95%置信区间；同时通过卡帕（Kappa）指数检验各参考标准间的一致性。
研究结果：心肺适能与体质指数（PR=1.49，95%CI:1.27~1.75）、肌肉力量与体质指数（PR=1.55，95%CI:1.17~2.08）、心肺适能与肌肉力量（PR=1.81，95%CI:1.47~2.24）之间均存在显著关联。各参考标准间的一致性呈弱至中等水平：心肺适能与体质指数的一致性为48.8%（K=0.05，P=0.10），肌肉力量与体质指数的一致性为52.9%（K=0.09，P=0.001），心肺适能与肌肉力量的一致性为38.4%（K=0.22，P<0.001）。
研究结论：尽管健身健康测评（Fitnessgram）针对心肺适能、肌肉力量及体质指数的参考标准之间存在显著关联，但各标准间的一致性仅处于弱至中等水平。鉴于单项测试均具备其特异性，在开展与健康相关的体适能评估时，建议同时实施所有相关测试项目。