The normative values of vertical jump and sit-and-reach in a large general Chinese population aged 8–80 years: The China National Health Survey

The normative values of vertical jump (VJ) and sit-and-reach (SR) for Chinese people are still unclear. We aimed to determine these values and their correlations with body composition using data from China National Health Survey which included 19,269 participants aged 8–80 years. Sex-specific smoothed centile tables were generated for the P1, P5, P25, P50, P75, P95, and P99 centiles of VJ and SR using lambda-mu-sigma method. The median (Interquartile range) values of VJ and SR in males and females were as follows: 20.3 (8.8) cm and 14.1 (5.5) cm for VJ, 1.8 (11.6) cm and 6.8 (10.4) cm for SR, respectively. In males, VJ values increased to a peak around the age of 18, with the 5th and 95th values being 17.7 cm and 41.3 cm, respectively. After reaching the peak, VJ values gradually declined with age. In females, VJ values remained relatively stable from childhood to early adulthood, and then declined after the age of 30. The peak values of SR were observed in early adulthood in both sexes, and remained stable in females but declined with age in males. VJ had a negative association with body composition, particularly in females. SR was found to have a negative association with fat mass indexes in males. However, correlations in females were only marginally statistically significant. The study provides age- and sex-specific percentile reference values for VJ and SR in Chinese people and can aid in the assessment of muscle fitness and facilitate early prediction of neuromuscular disorders.