Table 2.

Participants' characteristics per age group

	Age category, years
	8 and 9	10 and 11	12 and 13	14 and 15	16–18
Boys	n = 19	n = 22	n = 27	n = 22	n = 27
Age, years	9.1±0.6	11.0±0.6	13.0±0.6	15.1+0.5	17.4±1.0
Body mass, kg	34.6±4.9	41.2±7.4	46.9±9.3	65.6±14.3	65.3±9.7
Body height, cm	140±7	151±8	158±8	175±7	177±6
Age from PHV, years	–3.6±0.4	–2.3±0.6	–1.0±0.7	1.2±0.8	2.8±0.8
BMI	17.7±2.4	17.9±2.3	18.6±2.4	21.4±4.2	20.8±2.3
BSA, m2	1.15±0.10	1.31±0.15	1.43±0.17	1.78±0.22	1.78±0.16
Body fat, %	18.6±5.1	18.4±4.8	17.4±5.3	17.8±6.0	16.5±3.7
FFM, kg	28.0±3.0	33.4±4.8	38.4±5.8	53.2±8.2	54.3±6.7
FEV1 % of pred.	93.8±8.2	92.5±7.2	94.9±9.8a	98.6±10.9b	110.3±13.9c
FVC, % of pred.	90.2±7.2	88.7±6.7	93.6±9.5a	97.4±10.2b	108.2±12.5c
Girls	n = 23	n = 21	n = 37	n = 24	n = 29
Age, years	9.1±0.6	11.1±0.5	13.0±0.6	14.9±0.6	17.5±1.0
Body mass, kg	32.7±6.4	43.6±8.0	50.3±9.6	60.4±10.7	61.9±9.8
Body height, cm	138±6	153±6	162±7	169±6	166±7
Age from PHV, years	–2.3±0.6	–0.5±0.6	1.1±0.7	2.6±0.5	3.7±0.4
BMI	17.0±2.7	18.7±2.7	19.2±3.1	21.2±3.1	22.3±2.3
BSA, m2	1.11±0.13	1.35±0.15	1.49±0.17	1.68±0.17	1.69±0.16
Body fat, %	21.9±5.5	23.5±5.7	21.7±4.7	23.6±4.4	23.8±3.8
FFM, kg	25.3±3.6	33.0±4.2	39.1±5.9	45.8±6.2	46.9±5.6
FEV1, % of pred.	92.2±7.0	87.8±10.0	95.1±8.7d	101.7±11.4e	108.0±10.1f
FVC, % of pred.	89.0±7.0	84.3±10.3	90.2±8.9d	100.5±9.8e	103.9±8.0f

Values are presented as mean ± SD. BMI, body mass index; BSA, body surface area; FEV₁, forced expiratory volume in 1 s; FFM, fat-free mass; FVC, forced vital capacity; PHV, peak height velocity.

^aIn this case, n = 22.

^bIn this case, n = 17.

^cIn this case, n = 23.

^dIn this case, n = 25.

^eIn this case, n = 18.

^fIn this case, n = 22.