How does resistance training primarily improve bone density?

Resistance training primarily improves bone density by creating stress on the bones, which stimulates bone growth. When resistance is applied through weight training or other forms of strength training, the bones experience mechanical loading. This mechanical stress triggers a biological response, whereby osteoblasts (the cells responsible for bone formation) increase their activity to strengthen and remodel the bone structure.

The process of bone remodeling involves the balance between bone resorption (the breakdown of bone) and bone formation. When resistance training is performed, the added strain encourages the body to adapt by increasing bone mass and density to better handle future stresses. This adaptive response is crucial for maintaining healthy bone tissue and reducing the risk of osteoporosis and fractures as one ages.

While other factors such as decreasing body fat percentage and increasing cardiovascular endurance have health benefits, they do not directly contribute to the specific mechanism of enhancing bone density in the way that mechanical stress applied through resistance training does. Thus, the focus on bone stimulation is key to understanding how resistance training impacts bone health.