Table 1 Summary characteristics of eligible studies (n = 40)

Participants

– Number of randomized participants: 12–439

– Mean age: 15.5–71.0 years

– Mean BMI: 19.9–39.0 kg/m²

– Hormonal groups:

  – Pre-menopausal: n = 10

  – Peri-menopausal: n = 1

  – Post-menopausal: n = 13

  – Polycystic ovary syndrome (PCOS): n = 12

  – Per-partum: n = 1

  – Post-partum: n = 2

  – Unspecified: n = 1

Interventions

– Type of exercise:

  – Endurance: n = 17

  – Resistance: n = 6

  – Endurance and resistance: n = 11

  – Yoga/Tai chi: n = 2

  – Free choice or education to exercise: n = 4

– Modality

  – Supervision/monitoring

    – Direct or indirect supervision ± monitored exercise: n = 25

    – Monitored only exercise: n = 3

    – Mix of supervised and not supervised exercises: n = 4

    – No supervision: n = 5

    – Unknown: n = 3

  – Group sessions:

    – Exercise within group sessions: n = 5

    – Unknown: n = 35

– Intensity:

  – Light: n = 1

  – Moderate: n = 9

  – High: n = 19

  – Unknown: n = 11

– Frequency:

  – <3 days/week: n = 5

  – 3 to <5 days/week: n = 21

  – ≥5 days/week: n = 10

  – Unknown: n = 4

– Total duration:

  – <3 months: n = 2

  – 3 to <6 months: n = 20

  – 6 to <12 months: n = 9

  – ≥12 months: n = 9

– Co-intervention:

  – No co-intervention: n = 23

  – Diet: n = 12

  – Other: n = 8

Comparators

– No intervention: n = 19

– Diet: n = 6

– Other interventions: n = 19