High-Intensity Exercise and Geometric Indices of Hip Bone Strength in Postmenopausal Women on or off Bone Medication: The MEDEX-OP Randomised Controlled Trial.

To compare the effects of high-intensity resistance and impact training (HiRIT) to low-intensity, Pilates-based exercise (LiPBE) on proximal femur geometry and explore the influence of antiresorptive medication on those effects. Postmenopausal women with low bone mass, on or off antiresorptive bone medications were randomly allocated, stratified on medication intake, to eight months of twice-weekly, supervised HiRIT (Onero™) or LiPBE (Buff Bones®). 3D hip software was used to analyse proximal femur DXA scans. Outcomes included femoral neck (FN) and total hip (TH), volumetric (e.g. vBMC, vBMD) and geometric (e.g. cortical thickness, cross-sectional area [CSA], section modulus [Z]) indices of bone strength. Data were analysed using analysis of variance. Scans of 102 women were examined: LiPBE, 43; HiRIT, 37; LiPBE-med, 11; HiRIT-med, 11. HiRIT improved TH trabecular vBMC and vBMD (3.1 ± 1.1% versus - 1.2 ± 1.2%, p = 0.008; and 1.5 ± 1.0% versus - 1.6 ± 1.2%, p = 0.042, respectively) and FN and TH total vBMC (2.0 ± 0.8% versus - 0.2 ± 0.7%, p = 0.032; and 0.7 ± 0.4% versus - 0.8 ± 0.6%, p = 0.032, respectively), compared to losses in LiPBE. HiRIT also increased Z while LiPBE did not (p = 0.035). The combination of HiRIT and medication achieved greater improvements in FN total and trabecular vBMD, total BMC, CSA and Z than HiRIT alone. HiRIT improved geometric parameters of proximal femur strength, while LiPBE exercise was largely ineffective. Medication may enhance some HiRIT effects. Findings suggest reduced hip fracture risk in response to HiRIT.Trial registration number ACTRN12617001511325.

A Comparison of Bone-Targeted Exercise With and Without Antiresorptive Bone Medication to Reduce Indices of Fracture Risk in Postmenopausal Women With Low Bone Mass: The MEDEX-OP Randomized Controlled Trial.

The goal of the MEDEX-OP trial was to compare the efficacy of a known effective high-intensity resistance and impact training (HiRIT) with a low-intensity exercise control (Buff Bones® [BB]), alone or in combination with antiresorptive bone medication, on indices of fracture risk (bone mass, body composition, muscle strength, functional performance), compliance, and safety. Primary study outcomes were 8-month change in lumbar spine (LS) and total hip (TH) bone mineral density (BMD). Healthy postmenopausal women with low bone mass (T-score ≤ -1.0) on or off stable doses (≥12 months) of antiresorptive medication were recruited. A total of 115 women (aged 63.6 ± 0.7 years; body mass index [BMI] 25.5 kg/m2 ; femoral neck [FN] T-score -1.8 ± 0.1) were randomly allocated to 8-month, twice-weekly, 40-minute HiRIT (5 sets of 5 repetitions, >80% to 85% 1 repetition maximum) or BB (low-intensity, Pilates-based training), stratified by medication intake, resulting in four groups: HiRIT (n = 42), BB (n = 44), HiRIT-med (n = 15), BB-med (n = 14). HiRIT improved LS BMD (1.9 ± 0.3% versus 0.1 ± 0.4%, p < 0.001) and stature (0.2 ± 0.1 cm versus -0.0 ± 0.1 cm, p = 0.004) more than BB. Both programs improved functional performance, but HiRIT effects were larger for leg and back muscle strength and the five times sit-to-stand test (p < 0.05). There was a positive relationship between maximum weight lifted and changes in LS BMD and muscle strength in the HiRIT groups. Exploratory analyses suggest antiresorptive medication may enhance exercise efficacy at the proximal femur and lumbar spine. Exercise compliance was good (82.4 ± 1.3%) and both programs were well tolerated (7 adverse events: HiRIT 4; BB 3). HiRIT improved indices of fracture risk significantly more than Buff Bones®. More trials combining bone medication and bone-targeted exercise are needed. © 2021 American Society for Bone and Mineral Research (ASBMR).