Table 2 Extracted data relating to types of recreational physical activity

Coldman [6]

CCS

Cycling Horse-riding Motorcycling Soccer

Regular participation throughout lifetime

OR

Cycling 1.99 (1.04–3.81)

44 exposed 84 non-exposed

(34% exposed)

28 exposed

100 non-exposed

(22% exposed)

Controls matched for age and year of diagnosis but analysed in unmatched fashion

Adjust cycling and horse-riding for cryptorchidism, juvenile onset inguinal hernia and for each other

Horse-riding 3.31 (1.36–8.25)

25 exposed 103 non-exposed

(20% exposed)

9 exposed

119 non-exposed

(7% exposed)

Motorcycling

1.04 (0.43–2.41

16 exposed

112 non-exposed

(13% exposed)

15 exposed

113 non-exposed

(12% exposed)

Soccer 1.11 (0.50–2.50)

8 exposed

110 non-exposed (14% exposed)

16 exposed

112 non-exposed

(13% exposed)

Cycling as a teenager for recreation or for transport to school

Regular participation as a teen

In teens Cycling for recreation

1.81 (0.88–3.75)

62 exposed

66 non-exposed

(48% exposed)

49 exposed

79 non-exposed

(38% exposed)

Cycling to school 1.79 (0.91–3.55)

40 exposed

88 non-exposed

(31% exposed)

27 exposed

101 non-exposed

(21% exposed)

Frequency of horse riding

≥1 time/mth for ≥1 year

Frequent v.s. non-frequent

2.09 (0.88–5.08)

21 exposed 107 non-exposed

(16% exposed)

11 exposed 117 non-exposed

(9% exposed)

Forman [20]

CCS

Cycling Horse-riding Contact sports (football, rugby, hockey, lacrosse) Racquet sports Water sports Athletics Cricket, baseball and rounders

Martial arts

Regular participation at ref. age, age 16 and age 20

OR

Cycling, horse-riding, racquet sports, cricket, baseball and rounders

Unrelated to TC risk

Information not provided

Information not provided

Controls matched for age

Additional adjustment for cryptorchidism, juvenile onset inguinal hernia and total exercise

Contact sports

At ref. age

0.73 (0.55–0.97)

At age 20

0.80 (0.64–1.00

Water sports

At ref. age

0.87 (0.66–1.16)

At age 16

0.74 (0.58–0.96)

At age 20

0.74 (0.56–0.98

Athletics

At ref. age

0.70 (0.51–0.97

Martial arts

At ref. age

0.67 (0.29–1.54)

At age 16

0.42 (0.21–0.82)

At age 20

0.52 (0.29–0.94)

Littman [22]

CCS

Cycling

Horse-riding

Motor biking

Mountain biking

Soccer

Basketball

Wrestling

Regular participation during grades 7–12-yes/no

OR

Cycling

1.0 (0.7–1.3)

250 exposed

141 non-exposed

(64% exposed)

658 exposed

365 non-exposed

(64% exposed)

Controls matched for age and area of residence

Additional adjustment for income, ethnicity, cryptorchidism.

Each activity further adj. For all other activities

Horse-riding

0.8 (0.6–1.1)

68 exposed

323 non-exposed

(17% exposed)

210 exposed

813 non-exposed

(21% exposed)

Motor biking

0.9 (0.7–1.2)

144 exposed

247 non-exposed

(37% exposed)

409 exposed

614 non-exposed

(40% exposed)

Mountain

biking 0.9 (0.6–1.3)

51 exposed

263 non-exposed (16% exposed)

143 exposed

734 non-exposed (16% exposed)

Duration of participation during grades 7–12 in tertiles

Soccer 1–8 months

1.9 (1.2–3.1)

Basketball 1–8 months

1.5 (1.0–2.2)

Wrestling

6–11 months

0.4 (0.2–0.8)

≥12 months

0.8 (0.4–1.4)