Table 1 Demographic, reproductive, training, and metabolic characteristics of participants categorized by exercise and menstrual status

Demographic characteristics

Age (years)

24.9 ± 1.1

23.6 ± 1.2

24.9 ± 2.2

22.6 ± 0.9

21.6 ± 0.6

0.068

24.5 ± 0.8

0.004

Height (cm)

164 ± 1

166 ± 2

166 ± 1

166 ± 1

166 ± 1

0.869

165 ± 1

0.589

Weight (kg)

57.8 ± 1.3

59.5 ± 1.7

60.2 ± 1.2

58.1 ± 1.4

56.9 ± 1.3

0.594

58.8 ± 0.8

0.204

BMI (kg/m²)

21.4 ± 0.4

22.1 ± 0.3

21.8 ± 0.5

21.0 ± 0.4

20.7 ± 0.4

0.191

21.7 ± 0.2

0.045

Body fat (%)

25.2 ± 0.8

26.4 ± 1.3

26.0 ± 1.7

25.0 ± 1.2

25.0 ± 1.0

0.905

25.7 ± 0.6

0.526

Fat mass (kg)

14.5 ± 0.6

15.7 ± 1.0

15.5 ± 1.3

14.2 ± 0.8

14.4 ± 0.7

0.743

15.1 ± 0.5

0.410

Lean body mass (kg)

41.5 ± 0.9

41.2 ± 0.6

43.5 ± 0.7

42.0 ± 1.2

40.2 ± 0.8

0.318

41.9 ± 0.5

0.076

Reproductive characteristics

Age of menarche (years)

12.2 ± 0.3

12.1 ± 0.4

12.4 ± 0.5

13.4 ± 0.4

13.5 ± 0.3^a

0.006

12.2 ± 0.2

<0.001

Gynecological age (years)

12.7 ± 1.1

11.5 ± 1.2

12.4 ± 2.3

8.8 ± 1.0

8.0 ± 0.6^a

0.002

12.2 ± 0.8

<0.001

Training characteristics

VO_2peak (ml/kg/min)

47.3 ± 1.1

44.5 ± 1.4

46.3 ± 2.4

45.4 ± 0.9

45.4 ± 1.6

0.841

46.2 ± 0.8

0.656

Exercise volume (min/week)

338 ± 46

360 ± 57

377 ± 63

377 ± 61

357 ± 51

0.998

353 ± 31

0.934

Exercise frequency (sessions/week)

4.2 ± 0.4

4.7 ± 0.5

5.1 ± 0.7

4.6 ± 0.4

4.4 ± 0.3

0.819

4.4 ± 0.3

0.989

Exercise intensity (kcal/min)

6.1 ± 0.5

4.9 ± 0.4

4.9 ± 1.0

5.2 ± 0.5

6.2 ± 0.4

0.149

5.5 ± 0.3

0.145

Metabolic characteristics

TT₃

92.7 ± 3.2

93.5 ± 6.4

103.0 ± 8.9

90.4 ± 5.6

79.6 ± 4.1

0.048

95.3 ± 2.9

0.002

REE

32.0 ± 0.5

30.1 ± 0.5

29.2 ± 0.8

29.2 ± 0.8^a

29.7 ± 0.6

0.020

30.8 ± 0.4

0.112

REE/pREE

0.96 ± 0.02

0.90 ± 0.02

0.90 ± 0.03

0.87 ± 0.02^a

0.85 ± 0.02^a

0.005

0.92 ± 0.01

0.001