Here is the latest. It is a metanalysis or meta-analysis of multiple studies which basically is combining multiple studies to see a greater effect.
Meta-analysis is a method of synthesis of quantitative data from multiple independent studies addressing a common research question. An important part of this method involves computing a combined effect size across all of the studies. As such, this statistical approach involves extracting effect sizes and variance measures from various studies. By combining these effect sizes the statistical power is improved and can resolve uncertainties or discrepancies found in individual studies. Meta-analyses are integral in supporting research grant proposals, shaping treatment guidelines, and influencing health policies. They are also pivotal in summarizing existing research to guide future studies, thereby cementing their role as a fundamental methodology in metascience. Meta-analyses are often, but not always, important components of a systematic review.
Exercise and Bone Density: Does Modality Matter?
Context
Exercise is widely recommended for patients with low bone density and osteoporosis, but specific guidance on modality and quantity is based mostly on expert opinion. To assess how different forms of exercise affect bone mineral density (BMD) among adults aged 40 and older, investigators performed a network meta-analysis of 124 randomized trials involving 18,000 participants. Most trials lasted 6 to 12 months.
Key Results
- Brisk walking or jogging was the most effective form of exercise, improving BMD at all three sites measured: lumbar spine, total hip, and femoral neck. Combined aerobic–resistance exercise led to similar improvements for spine and femoral neck BMD but not total hip BMD.
- The other exercise programs evaluated (resistance training, mixed aerobic exercises, whole body vibration, and mind–body exercises like tai chi) generally had smaller effects on BMD, with benefits limited to only one or two sites.
- Clinically meaningful BMD improvements generally occurred at around 600 metabolic equivalent–minutes per week, which is about 2 to 3 hours of brisk walking or jogging.
- No type of exercise was associated with increased fracture risk.
Citation(s):
Lu C, et al. Effect of exercise on bone health in middle aged and older adults: Hierarchical network meta-analysis of randomised trials. BMJ 2026 Sep 9; 394:e100561. DOI: 10.1136/bmj-2026-100561. PubMed
Comment
Brisk walking or jogging is accessible for most patients and easy to recommend, so I’m glad to see that it may be particularly effective for improving bone density. We still don’t know for sure whether these increases in BMD lead to lower fracture risk, but harm is unlikely, and exercise has many other known benefits. Some sedentary patients feel hesitant about starting to exercise; I’d recommend starting with brief periods of brisk walking every day and gradually building toward a goal of 2 to 3 hours weekly.