Table 4

Fitness at age 17 years by LTPA groups and LTPA change groups, and the association of LTPA and LTPA change with fitness at age 17 years. Data are mean (SD) and range

		Fitness at age 17 y (ml/kg/min)
		Cohort A			Cohort B
		Age 13 years	n	p^*<0.0001	Age 9 years	n	p=0.30
LTPA	I (sedentary)	36.5 (6.2), 23.4–50.3^†	114		38.0 (6.5), 24.0–50.3	25
	II	41.5 (6.9), 27.5–58.0	133		39.2 (7.7), 24.7–55.0	25
	III (active)	43.3 (6.9), 26.5–58.0	104		43.2 (7.9), 27.5–55.5	24
		Age 13–17 years		p<0.0001	Age 9–17 years		p=0.0003
LTPA change	1) LTPA increase	36.6 (5.5), 27.1–49.7	51		39.4 (5.3), 27.3–50.3	17
	2) LTPA decrease	38.4 (6.3), 27.5–52.9	56		35.6 (6.0), 27.5–47.2	16
	3) Persistently sedentary	36.5 (6.8), 23.4–50.3	63		34.9 (8.1), 24.0–48.3	8
	4) Persistently active	43.5 (6.7), 26.5–58.0^‡	181		43.8 (7.5), 24.7–55.5^§	33

↵* p Values for the main effect of the covariate versus fitness at age 17 years, adjusted for gender.
↵† Tukey-Kramer adjusted p (sedentary vs active)<0.0001, p (sedentary vs moderately active) <0.0001.
↵‡ Tukey-Kramer adjusted p (persistently active vs persistently sedentary) <0.0001, p (persistently active vs LTPA decrease) <0.0001, p (persistently active vs LTPA increase) <0.0001.
↵§ Tukey-Kramer adjusted p (persistently active vs persistently sedentary)=0.0074, p (persistently active vs LTPA decrease)=0.0011.
LTPA, leisure-time physical activity.