Effects of a 12-Month Supervised, Community-Based, Multimodal Exercise Program Followed by a 6-Month Research-to-Practice Transition on Bone Mineral Density, Trabecular Microarchitecture, and Physical Function in Older Adults: A Randomized Controlled Trial

Abstract

Multicomponent exercise programs are recommended to reduce fracture risk; however, their effectiveness in real‐world community settings remain uncertain. This 18‐month randomized controlled trial investigated the effects of a 12‐month, community‐based, supervised multicomponent exercise program followed by a 6‐month “research‐to‐practice” transition on areal bone mineral density (BMD), trabecular bone microarchitecture, functional performance, and falls in older adults at increased fracture risk. One‐hundred and sixty‐two adults aged ≥60 years with osteopenia or at increased falls risk were randomized to the Osteo‐cise: Strong Bones for Life multicomponent exercise program (n = 81) or a control group (n = 81). Exercise consisted of progressive resistance, weight‐bearing impact, and balance training (3‐days/week) performed at community leisure centers. Overall 148 (91%) participants completed the trial, and mean exercise adherence was 59% after 12 months and 45% during the final 6 months. After 12 months, there were significant net beneficial effects of exercise on lumbar spine and femoral neck BMD (1.0% to 1.1%, p < 0.05), muscle strength (10% to 13%, p < 0.05), and physical function (timed stair climb 5%; four‐square step test 6%; sit‐to‐stand 16%, p ranging <0.05 to <0.001), which persisted after the 6‐month transition. There were no significant effects of the 18‐month intervention on distal femur or proximal tibia trabecular bone microarchitecture or falls incidence, but per protocol analysis (≥66% exercise adherence) revealed there was a significant net benefit of exercise (mean [95% confidence interval] 2.8% [0.2, 5,4]) on proximal tibia trabecular bone volume fraction (Osteo‐cise 1.5% [−1.2, 4.2]; controls −1.3% [−2.6, 0.1]) after 18 months due to changes in trabecular number (Osteo‐cise 1.7% [−0.9, 4.3]; controls −1.1% [−2.4, 0.2]) but not trabecular thickness (Osteo‐cise − 0.2% [−0.5, 0.2]; controls −0.2% [−0.4, 0.0]). In conclusion, this study supports the effectiveness of the Osteo‐cise: Strong Bones for Life program as a real‐world, pragmatic, evidence‐based community exercise program to improve multiple musculoskeletal health outcomes in older adults at increased fracture risk. © 2019 American Society for Bone and Mineral Research.

Osteosarcopenia: epidemiology, diagnosis, and treatment—facts and numbers

“…Second, gravitational loading (via external ground forces or internal muscle contractions) is transferred from muscle to the skeleton, providing the mechanical stimuli to maintain bone density . Indeed, physical inactivity common in old age or in states of disuse (bed rest, hip fracture) results in atrophy of both tissues, while physical loading is hypertrophic to muscle and osteogenic to bone . Third, the metabolism of both tissues is similar in that amino acid availability determines the rate of protein turnover in muscle while contributing to the bone matrix by enabling collagen synthesis .…”

A clinical guide to the pathophysiology, diagnosis and treatment of osteosarcopenia

“…Muscle and bone are also highly malleable tissues and respond similarly to environmental stimuli. Following prolonged physical loading, significant increases in muscle mass, strength and physical functioning [25,26], as well as bone density and microarchitecture are evident [27]. In periods of bed rest/disuse, the opposite occurs with rapid declines in muscle mass and function and slower declines in bone density [28].…”

“…Regular participation in physical activity, especially resistance exercise (RE), offers benefits to the whole body [49]. Cross-sectional studies also demonstrate the benefits of RE on attenuating age-related losses of muscle and bone mass [27] and increases in adiposity [50]. Clinical trials in osteopenic/sarcopenic individuals offer further evidence that RE can improve multiple musculoskeletal health outcomes as well as quality of life [25,26], while others show a positive association between physical activity and reductions in falls and fractures [51,52].…”

A 12-month continuous and intermittent high-impact exercise intervention and its effects on bone mineral density in early postmenopausal women: a feasibility randomized controlled trial

“…For human populations, mechanical loading is generated through high-impact exercises which can be challenging for postmenopausal women despite the known benefits of high-impact exercise on bone health (14). It is common to find adherence rates ranging from 52 to 100 % in exercise interventions with osteopenic and osteoporotic populations, for which the most commonly reported barriers to participating in exercise activity are lack of time and lack of transportation (15)(16)(17). For exercise interventions targeting bone health in adult populations, the average dropout rate is 21% [95% confidence intervals (CI): 17 to 26%] with 24% [95% CI: 20 to 28%] of the remaining participants not fully complying with the intervention (18,19).…”