Purpose
High intensity resistance and impact training (HiRIT) improves bone, muscle and function in older women and men with low bone mass in clinical trials. Translation of HiRIT into effective therapy for osteoporosis was daunting due to the need for supervision, comorbid conditions, and a lack of Medicare reimbursement, prompting the establishment of a research clinic designed for safe delivery and data monitoring. Positive BMD and functional outcomes have previously been reported. Curiously, the outcomes least responsive to heavy weight-bearing loading are FN and total hip BMD suggesting the bone response to loading at the hip is structural not densitometric. The current report describes 3D hip analysis outcomes following 12 months of HiRIT at The Bone Clinic.
Methods
Clinic clients undergo comprehensive testing for biometrics, function, falls, fracture, and bone outcomes. Some undergo 3D hip analysis for indices of proximal femur strength. Twice-weekly supervised HiRIT is undertaken on a voluntary client basis. Adherence and injuries are recorded. Clients with >30% HiRIT adherence were included in the current analyses. In the absence of a control group in this clinical sample, outcomes were examined using repeated measures GLM comparing baseline and follow-up visit, adjusting for adherence.
Results
We report outcomes from 106 Clinic clients (62.0±7.4yrs, 161.4±12.2cm, 62.9±16.2kg, average adherence 63.1±24.8%). Improvements were observed in trochanteric trabecular volume (P<0.025) along with trochanteric cross-sectional moment of inertia (CSMI) (P<0.026) and section modulus (Z) (P<0.023), with a trend for increased total trabecular volume and total volume, despite a loss in femoral neck cross sectional area (P<0.026), and Z (P<0.017).
Conclusions
12 months of ‘real-world’ supervised HiRIT increased proximal femur trabecular volume which enhanced parameters of bone strength at the hip in individuals at risk of fracture. Long term monitoring of this unique translational dataset has confirmed the efficacy and appeal of exercise intervention for osteoporosis.