Mechanography in childhood: references for force and power in counter movement jumps and chair rising tests.

OBJECTIVE: We sought to procure age- and gender- related reference data and study the characteristics of body weight related peak force (pFrel), body mass related peak power (pPrel) for counter movement jumps (single two-legged jumps, s2LJ) and chair rising tests (CRT) in children. METHODS: We examined 868 healthy participants (436 female) aged 3 to 19 years. Weight-related results of the s2LJ and CRT Mechanography parameters were reported. RESULTS: pPrel during s2LJ (pPrel(s2LJ)) increased linearly with age for males age 5 to 19 and female age 5 to 11 at a rate of 4.6 W/kg per year. pPrel(s2LJ) for females age 12 to 19 increased only by 2.5 W/kg. CRT time per repetition was 1.065 s, independent of age and gender. pPrel per body mass during the rise phase (pPrel(CRT)) showed similar but smaller age and gender relations as peak power during s2LJ. pFrel was 2.5 g (multiples of earth's gravity) for s2LJ and 1.5 g for CRT. CONCLUSION: This data from normal children from a healthy Caucasian population provide reference values for tests that reflect everyday motor function.