From the Guidelines
Upper body weight lifting does not significantly induce bone growth in the lower extremities, and for optimal bone development in the legs, hips, and feet, exercises that directly load these areas through weight-bearing activities are necessary. The mechanical stress from upper body weight lifting primarily affects the bones being directly loaded during exercise, as stated by Wolff's Law, which says that bones adapt to the forces placed upon them 1. For lower body bone growth, exercises like squats, lunges, deadlifts, stair climbing, running, or jumping are recommended as they create direct mechanical loading on the lower extremities, stimulating osteoblast activity (bone-building cells) specifically in the loaded areas.
Some systemic hormonal benefits from upper body training may provide minimal indirect benefits to overall bone health, but these effects are relatively small compared to direct mechanical loading of the target bones. The most recent and highest quality study suggests that physical activity probably plays a role in the prevention of osteoporosis, with higher dose programs and those involving multiple exercises and resistance exercises appearing to be more effective 1. Key findings from a systematic review of 59 studies, including 20 randomized controlled trials, support the idea that physical activity has a significant but small effect on bone health, particularly in lumbar bone mineral density 1.
In terms of specific recommendations for exercise, the evidence suggests that programs undertaken for 60+ minutes, 2-3 times a week, for 7+ months are likely to have a significant impact on bone health 1. It's also important to note that while upper body resistance training is valuable for overall health and upper body bone density, it is not a substitute for weight-bearing exercises that directly load the lower extremities. Incorporating exercises that directly load the lower extremities is crucial for optimal bone development and osteoporosis prevention in the legs, hips, and feet.
From the Research
Upper Body Weight Lifting and Bone Growth
- The provided studies do not directly address the question of whether upper body weight lifting can induce bone growth in lower extremities 2, 3, 4, 5, 6.
- However, one study suggests that impact-loading exercise, which can be part of a weight lifting routine, can have an osteogenic effect on bone mineral density in middle-aged and older men, particularly in the hip and trochanter regions 3.
- Another study discusses the importance of calcium and vitamin D supplementation for maintaining bone health and preventing osteoporosis, which could be relevant to bone growth in general 5, 6.
- It is also worth noting that the studies provided focus on the prevention and treatment of osteoporosis, and the role of exercise and nutrition in maintaining bone health, rather than specifically addressing the question of upper body weight lifting and bone growth in lower extremities 2, 4.
Exercise and Bone Health
- Regular exercise, including resistance training and impact-loading exercise, is recommended as a potential strategy to counteract age-related bone loss 3.
- However, the optimal exercise prescription for inducing bone growth in specific regions, such as the lower extremities, is not well established 3.
- The studies provided suggest that a combination of exercise and nutrition, including calcium and vitamin D supplementation, may be beneficial for maintaining bone health and preventing osteoporosis 5, 6.
Limitations and Future Research
- The provided studies have limitations, including small sample sizes and limited durations, which may affect the generalizability of the results 3, 5, 6.
- Further research is needed to fully understand the effects of upper body weight lifting on bone growth in lower extremities, and to determine the optimal exercise and nutrition strategies for maintaining bone health and preventing osteoporosis 2, 3, 4, 5, 6.