From the Guidelines
Resistance-based training is a crucial component of exercise routines for preventing bone mineral density (BMD) loss, particularly in older adults, and should be prioritized to reduce the risk of osteoporosis. According to a systematic review published in the International Journal of Behavioral Nutrition and Physical Activity in 2020 1, physical activity interventions, including resistance training, probably improve bone health among older adults. The review found that higher doses of physical activity and programs involving multiple exercise types or resistance exercise appear to be most effective in improving lumbar spine bone mineral density and may improve hip bone mineral density.
Key characteristics of an effective resistance training program for preventing BMD loss include:
- 2-3 sessions per week of progressive resistance training targeting major muscle groups
- 8-12 repetitions per exercise at moderate to high intensity (60-80% of one-repetition maximum)
- Exercises that focus on weight-bearing movements, such as squats, lunges, deadlifts, and overhead presses, which create mechanical loading on bones
- Combination with impact activities like jumping or stair climbing
- Adequate calcium intake (1000-1200mg daily) and vitamin D (600-800 IU daily)
The mechanism by which resistance training prevents BMD loss involves creating mechanical stress on bones through muscle contractions, stimulating osteoblast activity and bone formation through mechanotransduction 1. This process triggers cellular responses that strengthen bone structure, particularly in areas prone to fracture, such as the hips and spine. Even older adults and those with existing low BMD can benefit from properly supervised resistance training, with modifications as needed for safety and effectiveness.
From the Research
Resistance Training and BMD Loss
- Resistance training has been shown to be effective in maintaining and improving bone mineral density (BMD) and bone strength 2.
- It is thought that resistance training affects bone metabolism through direct biomechanical force on bone cells and endocrinological factors as well as the nervous system 2.
- Resistance training in combination with other types of exercise might be effective for maintaining BMD in patients with osteoporosis 2, 3.
Effects of Resistance Training on BMD
- Studies have found that resistance training can improve BMD in older adults with osteopenia or osteoporosis 4.
- Strength training has a significant positive influence on BMD in older women with osteoporosis or osteopenia, but it is not recommended to only rely on strength training as the increase of BMD may not appear fast enough to reach the minimal desired values 4.
- A combination of strength training and supplements/medication seems most adequate for older women with reduced BMD 4.
Comparison with Other Interventions
- High-intensity interval training (HIIT) and vitamin D supplementation have been shown to have greater benefits for BMD levels in women with osteoporosis than either vitamin D consumption or HIIT training alone 5.
- Bisphosphonates reduce the risk of fracture by suppressing bone resorption and increasing bone strength, and they have been widely used for the prevention and treatment of osteoporosis 6.
Key Findings
- Four of the 5 reviewed studies with the highest evidence showed a significant increase in lumbar spine BMD after strength training interventions in comparison with control groups 4.
- The fifth study confirmed the maintenance of lumbar spine density due to conducted exercises 4.
- Three reviewed studies revealed increasing BMD at the femoral neck after strength training when compared with controls, which appeared significant in 2 of them 4.