Table 1 Included studies categorized by study characteristics

Low

30

38%

[1, 2, 4, 12, 14,15,16, 18, 20, 23,24,25,26, 31, 34, 36, 40, 42,43,44, 49, 50, 57, 59, 60, 62, 67, 75,76,77]

Medium

41

53%

[5,6,7,8,9, 13, 17, 21, 22, 28,29,30, 32, 33, 35, 37,38,39, 45,46,47,48, 51, 55, 56, 58, 61, 63,64,65,66, 68,69,70,71,72,73,74, 78]

High

7

9%

[3, 19, 27, 41, 52,53,54]

< 100

5

6%

[5, 17, 41, 53, 71]

100–299

19

24%

[4, 6, 7, 9, 10, 13, 21, 27, 29, 32, 48, 51, 52, 66, 68, 70, 73, 75, 76]

300–499

9

12%

[3, 8, 16, 33, 38, 39, 49, 72, 78]

500–1999

25

32%

[15, 18, 19, 22,23,24,25,26, 30, 31, 35, 40, 43, 44, 46, 47, 50, 54, 55, 60, 61, 63, 65, 69, 74]

2000–4999

14

18%

[1, 12, 14, 20, 34, 36, 42, 45, 56, 57, 59, 62, 67, 77]

> 5000

6

8%

[2, 11, 28, 37, 58, 64]

North America

31

40%

[1, 2, 4, 5, 10,11,12, 14, 17, 19, 21, 22, 28, 33, 34, 37, 42,43,44, 50,51,52,53, 57, 59, 60, 63, 65, 67, 69, 77]

Europe

29

37%

[6, 7, 18, 20, 23,24,25,26,27, 29, 30, 36, 38, 40, 45, 47,48,49, 55, 56, 62, 64, 66, 70, 71, 75, 76]

Asia

14

18%

[13, 16, 32, 35, 39, 41, 54, 58, 61, 68, 72,73,74, 78]

Oceania (including Australia)

4

5%

[3, 15, 31, 46]

High-income countries

74

95%

[1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20,21,22,23,24,25,26,27,28,29, 33,34,35,36,37,38,39,40,41,42,43,44,45,46,47,48,49,50,51,52,53,54,55,56,57,58,59,60, 62,63,64,65,66,67,68,69,70,71, 74,75,76,77,78]

Upper-middle-income countries

2

3%

[72, 73]

Lower-middle-income countries

2

3%

[32, 61]

Low-income countries

0

0%

–

Canada

1

1%

[51]

United States

30

38%

[1, 2, 4, 5, 10,11,12, 14, 17, 19, 21, 22, 28, 33, 34, 37, 42,43,44, 50, 52, 53, 57, 59, 60, 63, 65, 67, 69, 77]

Finland

5

6%

[23, 30, 45, 47, 66]

Sweden

3

4%

[6, 7, 64]

Norway

3

4%

[18, 55, 62]

Netherlands

4

5%

[8, 38, 70, 71]

Germany

6

8%

[20, 25, 26, 29, 36, 40]

United Kingdom

2

3%

[24, 49]

Belgium

2

3%

[48, 76]

Lithuania

1

1%

[27]

Italy

1

1%

[56]

Spain

1

1%

[75]

Israel

3

4%

[16, 35, 58]

Jordan

1

1%

[32]

India

1

1%

[61]

China

2

3%

[72, 73]

Korea

2

3%

[39, 78]

Japan

5

6%

[13, 41, 54, 68, 74]

Australia

2

3%

[15]

New Zealand

2

3%

[31, 46]

Multiple countries

1

1%

[9]

Cross-sectional

59

76%

[1,2,3, 9,10,11,12,13,14, 16, 18,19,20,21, 23,24,25,26,27,28,29,30, 32,33,34,35,36, 39,40,41,42,43,44,45, 47,48,49,50,51,52, 54, 56,57,58,59, 61, 62, 65,66,67,68,69, 72, 74, 75, 77, 78]

Longitudinal

18

23%

[6, 15, 17, 22, 31, 37, 38, 46, 53, 55, 60, 63, 64, 70, 73, 76]

Case–control

1

1%

[71]

Women only

8

10%

[13, 19, 28, 39, 52, 53, 63, 73]

Men only

17

22%

[3, 5, 10, 17, 23, 32, 35, 45, 47, 48, 50, 55, 56, 61, 64, 74, 76]

Women and men

48

62%

[2, 4, 6,7,8, 11, 12, 14,15,16, 18, 20,21,22, 24,25,26,27, 29, 30, 33, 34, 36,37,38, 40,41,42,43,44, 49, 51, 54, 57,58,59,60, 65,66,67,68,69,70,71,72, 75, 78, 79]

NR

5

6%

[1, 9, 31, 46, 62]

Maximal

48

62%

[8, 11,12,13, 16,17,18, 21,22,23, 25,26,27,28,29,30, 33,34,35,36,37,38,39,40, 45, 47, 48, 51,52,53, 55,56,57, 59,60,61, 63,64,65,66, 69,70,71, 73,74,75, 77]

Submaximal

27

35%

[1, 5,6,7, 9, 14, 15, 19, 20, 24, 31, 41,42,43,44, 46, 49, 50, 54, 58, 62, 67, 68, 72, 76]

NR

3

4%

[10, 32, 78]

Cycle

34

44%

[3, 5,6,7, 9, 13, 15, 20, 23,24,25,26,27, 30,31,32, 36, 40, 45,46,47,48, 51, 55, 56, 64, 66, 68, 71,72,73,74,75,76]

Treadmill

44

56%

[1, 2, 4, 8, 10,11,12, 14, 16,17,18,19, 21, 22, 28, 29, 33,34,35, 37,38,39, 41,42,43,44, 49, 50, 52,53,54, 57,58,59,60,61,62,63, 65, 67, 69, 70, 77, 78]

 VO_2max, direct (among others)

39

50%

[4, 5, 8, 10, 13, 17, 18, 21,22,23,24,25,26,27, 29, 30, 33, 35, 38,39,40, 45, 47,48,49, 51,52,53,54, 62, 65, 66, 69,70,71,72,73, 75, 76]

VO_2max indirect (among others)

19

24%

[1, 6, 7, 9, 14, 16, 31, 41,42,43,44, 46, 50, 67, 68, 74, 77]

Only other measures

19

24%

[11, 12, 15, 19, 20, 28, 32, 34, 36, 37, 55,56,57,58,59,60,61, 63, 64]

NR

1

1%

[78]