Table 2 Participant demographics by sport specialization

Age, mean (SD)

13.40 (0.63)

13.85 (0.94)

13.61 (0.81)

 Male

16 (84.2)

8 (47.1)

24 (66.7)

 Female

3 (15.8)

9 (52.9)

12 (33.3)

 Asian

15 (79.0)

5 (29.4)

20 (55.6)

 White/Caucasian

4 (21.1)

12 (70.6)

16 (44.4)

 < 18.5 (underweight)

8 (42.1)

8 (47.1)

16 (44.4)

 18.5–24.9 (normal weight)

10 (52.6)

8 (47.1)

18 (50.0)

 25–29.9 (overweight)

0 (0)

1 (5.9)

1 (2.8)

 30–39.9 (obese)

1 (5.3)

0 (0)

1 (2.8)

 Left

1 (5.3)

3 (17.7)

4 (11.1)

 Right

18 (94.7)

14 (82.4)

32 (88.9)

 None

15 (79.0)

10 (58.8)

25 (69.4)

 Allergic rhinitis

1 (5.3)

1 (5.9)

2 (5.6)

 Asthma

1 (5.3)

1 (5.9)

2 (5.6)

 Atopic dermatitis

0 (0)

1 (5.9)

1 (2.8)

 Attention deficit

0 (0)

1 (5.9)

1 (2.8)

 Attention deficit with hyperactivity

0 (0)

1 (5.9)

1 (2.8)

 Previous lower extremity injury

1 (5.3)

1 (5.9)

2 (5.6)

 Rhinitis

2 (10.5)

0 (0)

2 (5.6)

 Scoliosis

0 (0)

1 (5.9)

1 (2.8)

 Light

0 (0)

2 (11.8)

2 (5.6)

 Moderate

1 (5.3)

4 (23.5)

5 (13.9)

 Vigorous

18 (94.7)

11 (64.7)

29 (80.6)

Hours per week playing sports, mean (SD)

3.32 (1.83)

3.76 (2.33)

3.53 (2.06)

 Soccer

7 (36.8)

9 (52.9)

16 (44.4)

 Hockey

3 (15.8)

6 (35.3)

9 (25.0)

 Basketball

1 (5.3)

5 (29.4)

6 (16.7)

 Racquet sports

3 (15.8)

2 (11.8)

5 (13.9)

 Volleyball

2 (10.5)

3 (17.7)

5 (13.9)

 Skiing/snowboard

0 (0)

5 (29.4)

5 (13.9)

 Archery

3 (15.8)

0 (0)

3 (8.3)

 Multiple sports

0 (0)

3 (17.7)

3 (8.3)

 Cycling

0 (0)

2 (11.8)

2 (5.6)

 Football

0 (0)

2 (11.8)

2 (5.6)

 Running (long)

0 (0)

2 (11.8)

2 (5.6)

 Running (short)

0 (0)

2 (11.8)

2 (5.6)

 Swimming

0 (0)

2 (11.8)

2 (5.6)

 Equestrian

0 (0)

1 (5.9)

1 (2.8)

 Gymnastics

0 (0)

1 (5.9)

1 (2.8)

 Lacrosse

0 (0)

1 (5.9)

1 (2.8)

 Weightlifting

0 (0)

1 (5.9)

1 (2.8)

 Frisbee

0 (0)

1 (5.9)

1 (2.8)

 Hiking

0 (0)

1 (5.9)

1 (2.8)