EFFECTS-262 Research Group, Department of Physiology, Faculty of Medicine, University of Granada, Granada, Spain.
PROFITH "PROmoting FITness and Health Through Physical Activity" Research Group, Sport and Health University Research Institute (iMUDS), Department of Physical and Sports Education, Faculty of Sport Sciences, University of Granada, Granada, Spain.
Am J Hum Biol. 2023 Nov;35(11):e23945. doi: 10.1002/ajhb.23945. Epub 2023 Jun 20.
Cardiorespiratory fitness and fatness indicators have been related to heart rate variability (HRV) parameters. The Fit-Fat Index (FFI) is a single index combining cardiorespiratory fitness and fatness indicators. To the best of our knowledge, no studies have previously analyzed whether FFI are related to cardiac autonomic nervous system activity assessed through HRV parameters. This study aimed (i) to examine the association of cardiorespiratory fitness, fatness indicators, and FFI with HRV parameters; and (ii) to report what of the different fatness indicators included in FFI is better associated with HRV parameters in sedentary adults.
One hundred and fifty healthy adults (74 women; 76 men), aged between 18 and 65 years old, participated in this cross-sectional study. We measured cardiorespiratory fitness (maximal oxygen consumption) and fatness indicators (waist-to-height ratio [WHR], fat mass percentage [FM%] and visceral adipose tissue [VAT]). Three FFIs were calculated as the quotient between cardiorespiratory fitness and one out of three possible fatness indicators: Fit-Fat Index calculated waist-to-height ratio (FFI ), Fit-Fat Index calculated with FM% (FFI ), and Fit-Fat Index calculated with VAT (FFI ). HRV parameters were measured in resting conditions using a Polar RS800CX.
FFI , FFI and FFI were related to different HRV parameters (β ranges between -0.507 and 0.529; R ranges between 0.096 and 0.275; all p < .001) and the association was stronger with HRV parameters than the isolated fitness or fatness indicators (β ranges between -0.483 and 0.518; R ranges between 0.071 and 0.263; all p < .001). FFI was the index more consistently associated with HRV parameters (β ranges between -0.507 and 0.529; R ranges between 0.235 and 0.275; all p < .001).
Our study suggests that compound FFIs are better predictors of HRV parameters than either cardiorespiratory fitness or fatness indicators alone. The FFI was the best index in terms of its association to HRV.
心肺适能和肥胖指标与心率变异性（HRV）参数有关。Fit-Fat 指数（FFI）是一个结合心肺适能和肥胖指标的单一指数。据我们所知，以前没有研究分析 FFI 是否与通过 HRV 参数评估的心脏自主神经系统活动有关。本研究旨在：（i）研究心肺适能、肥胖指标和 FFI 与 HRV 参数的关系；（ii）报告 FFI 中包含的不同肥胖指标中哪一个与久坐成年人的 HRV 参数相关性更好。
本横断面研究共纳入 150 名 18-65 岁健康成年人（女性 74 名，男性 76 名）。我们测量了心肺适能（最大摄氧量）和肥胖指标（腰高比[WHR]、体脂百分比[FM%]和内脏脂肪组织[VAT]）。FFI 通过将心肺适能除以三个肥胖指标之一来计算，计算出三个 Fit-Fat 指数：FFI（计算的 WHR）、FFI（计算的 FM%）和 FFI（计算的 VAT）。HRV 参数在静息状态下使用 Polar RS800CX 测量。
FFI、FFI 和 FFI 与不同的 HRV 参数相关（β 范围在-0.507 到 0.529 之间；R 范围在 0.096 到 0.275 之间；所有 p<0.001），与 HRV 参数的相关性强于单独的健身或肥胖指标（β 范围在-0.483 到 0.518 之间；R 范围在 0.071 到 0.263 之间；所有 p<0.001）。FFI 是与 HRV 参数相关性最强的指数（β 范围在-0.507 到 0.529 之间；R 范围在 0.235 到 0.275 之间；所有 p<0.001）。
本研究表明，复合 FFI 比心肺适能或肥胖指标单独预测 HRV 参数更好。FFI 在与 HRV 的相关性方面是最佳指标。
