Physical fitness, cardiometabolic risk and heart rate recovery in Chilean children

Abstract

Objective: To evaluate the association of physical fitness (PF) and cardiometabolic risk (CMR) with heart rate recovery time (Delta HRR) in Chilean school aged children.

Methods: Cross-sectional study in 478 6-9 years old children participants. We measured weight, height and abdominal circumference. Fitness was measured using the 6MWT, grip strength and leap forward without impulse tests; PF z-scores were calculated. Heart rate (HR) was monitored and recorded during the 6MWT. Delta HRR was calculated as the difference between HR before and one minute after test; blood glucose, insulin, triglycerides and HDL-cholesterol were measured. Waist circumference, CMR-z and HOMA were calculated.

Results: Absolute Delta HRR and CMR-z measures in normal weight children were lower than in obese children (p < 0.05 and p < 0.01, respectively). In obese children, Delta HRR was also associated with grip strength/weight (r = -0.6, p < 0.01) and PF-z (r = -0.6, p = 0.04). Insulin and HOMA were significantly related to Delta HRR (r = 0.3, p < 0.001), especially in overweight and obese children. Delta HRR values were not associated with CMR-z.

Conclusions: A significant relationship between Delta HRR with fitness and insulin sensitivity in overweight and obese school children was found. We consider that these results support the need to measure these variables in overweight and obese children, in order to strengthen the need for early prevention.

Objetivo: establecer la asociación entre la condición física (CF) y el riesgo cardiometabólico (RCM) con el tiempo de recuperación de la frecuencia cardiaca (ΔFCR) en escolares chilenos. Métodos: estudio trasversal de 478 escolares de 6 a 9 años de ambos sexos. Se evaluó peso, talla y perímetro abdominal. Se midió CF global mediante T6M, fuerza de agarre y salto hacia adelante sin impulso; se calculó z-CF. Se midió frecuencia cardiaca (FC) con sensor durante el T6M. Calculamos ΔFCRecup como la diferencia entre la FC en reposo y la FC al minuto de finalizado el test, glicemia, insulinemia, trigliceridemia y colesterol-HD. Perímetro de cintura, z-RCM y HOMA fueron calculados. Resultados: los escolares normopeso tuvieron menor ∆FCRecup y z-RCM que los obesos (p < 0,05 and p < 0,01 respectivamente). En niños obesos, el ∆FCRecup se asoció a fuerza de agarre/peso (r = -0,6, p < 0,01) y z-CF (r = -0,6, p = 0,04). Un menor ∆FCRecup se relacionó con menores niveles de insulinemia y HOMA (r = 0,3, p < 0,001), especialmente en el grupo de escolares con sobrepeso y obesidad. El ΔFCRecup no fue asociado a z-RCM. Conclusión: existe asociación entre el ΔFCRecup y la condición física y sensibilidad insulínica en escolares con sobrepeso y/u obesidad, lo que refuerza la necesidad de la medición de esta variable en niños con sobrepeso y obesidad para una prevención temprana.