Exercise and Bone Mineral Density in Premenopausal Women: A Meta-Analysis of Randomized Controlled Trials

Table 1

General characteristics of studies.

Study	Country	Participants	Exercise intervention	BMD Assessment
Bailey and Brooke-Wavell,; 2010 [14]	United Kingdom	85 healthy, premenopausal women 18 to 45 yrs of age assigned to 0 (𝑛=20), 2 (𝑛=21), 4 (𝑛=22), or 7 (𝑛=22) days/wk of exercise	2, 4, or 7 days/wk of 5 sets of 10 hops on one limb with 15 seconds of walking between each set for 6 months	DEXA (GE Lunar Prodigy Advance) at the FN
Friedlander et al.,; 1995 [15]	United States	63 women 20 to 35 yrs of age assigned to either an exercise (𝑛=32) or stretching (𝑛=31) group	3 days/wk, 1 h/session, alternating classes of circuit training, strength training, and aerobic exercise (70–85% of VO2max), for 2 yrs	DEXA (Hologic QDR 1000) at the LS & FN
Heinonen et al.,; 1996 [16]	Finland	84 healthy, sedentary premenopausal women 35 to 40 yrs of age assigned to either a training (𝑛=39) or control (𝑛=45) group	3 days/wk, 1 h/session (15 min warm-up, 20 min high- impact jump training, 15 min calisthenics, 10 min cool down), for 18 months	DEXA (Norland XR-26) at the LS & FN
Liang et al.,; 2011 [17]	United States	51 healthy, untrained women 20 to 35 yrs of age assigned to a strength training (𝑛=15), step aerobics (𝑛=16), or control (𝑛=20) group	3 days/wk, 40 min/session, strength: 1–3 sets, 8–15 reps, 65–80% 1RM, 8 exercises; step aerobics: step, hop, walk, run in place, 20 cm step height, 15–300 hop cycles/session, for 12 months	DEXA (Hologic QDR 4500W)
Lohman et al.,; 1995 [18]	United States	56 premenopausal women 28 to 39 yrs of age assigned to either an exercise (𝑛=22) or control (𝑛=34) group	3 days/wk, 1 h/session, 3 sets, 8–12 reps, 70–80% 1RM, 12 weight lifting exercises, 18 months	DEXA (Lunar DPX) at the LS & FN
Warren et al.,; 2008 [19]	United States	148 healthy, sedentary, overweight premenopausal women 25 to 44 yrs of age assigned to either an exercise (𝑛=72) or control (𝑛=76) group	2 days/wk, strength training, 3 sets, 8–10 reps, for 2 yrs	DEXA (Lunar Prodigy) at the LS & FN
Weaver et al.,; 2001 [20]	United States	55 women 18 to 31 yrs of age assigned to either an exercise (𝑛=28) or control (𝑛=27) group	3 days/wk of super circuit resistance training, 8 upper and 8 lower body exercises with a cycle ergometer between each station, 8–12 reps, 70% 1RM, plus 60 min of jumping rope/wk, for 24 months	DEXA (DXA Lunar) at the LS & FN

BMD: bone mineral density; DEXA: dual-energy X-ray absorptiometry; FN: femoral neck; LS: lumbar spine; yrs: years; min: minute(s); h: hour(s); wks: weeks; wk: week; RM: repetition maximum; reps: repetitions; VO_2max: maximum oxygen consumption; description of groups is limited to those that met the inclusion criteria for the current meta-analysis; description of BMD assessment is limited to the primary outcomes of the current meta-analysis (FN and LS). Number of participants is limited to those in which final BMD assessments were available.