A new study has linked physical activity levels to several key health indicators, including bone mineral density and body fat percentage.

In this article, we’ll delve into the details of this study. You’ll learn what these results mean for Savers and how to use them to build stronger bones and longer, more independent lives.

About The Study

A study published this June in the journal Scientific Reports analyzed the impact of sedentary activity and physical activity on bone mineral density (BMD) and body fat percentage.

Researchers used data from the National Health and Nutrition Examination Survey taken from 9,787 participants in America aged 20-59 between 2011 and 2018.

Participants’ activity levels were evaluated using questionnaires that inquired about the number of hours per day they spent each day engaging in vigorous or moderate physical activity andr being sedentary. Dual-energy X-ray Absorptiometry (DXA) scans were used to measure bone mineral density and total body fat percentage.

Subsequently, the researchers analyzed the relationships between various data points, adjusting for factors known to impact BMD and body fat, such as age, smoking, alcohol intake, levels of protein, Vitamin D, and serum uric acid levels.¹

Synopsis

A study of 9,787 Americans assessed the impact of sedentary activity and physical activity on bone mineral density and body fat percentage using questionnaires and DEXA scans. Scientists analyzed the data, accounting for confounding factors that could have also influenced the outcomes.

Sedentary Time Decreases Bone Density And Increases Fat

The researchers discovered a negative correlation between time spent being sedentary and lumbar spine bone mineral density. Less active participants had lower bone mineral density.¹

Participants' time spent sedentary positively correlated to total fat percentage. The less active participants were, the higher their total fat levels.

The opposite relationships were observed with physical activity levels.

Participants who spent more time moving their bodies had higher bone mineral density and lower total fat percentage.

Synopsis

The researchers found that sedentary participants had lower bone mineral density and higher fat percentage. More physically active participants had higher bone mineral density and lower fat percentage.

How A Sedentary Lifestyle Degrades Your Bones

Wolff’s Law describes the positive relationship between using your muscles and building your bones. It observes that bone adapts to use. The more you use a part of your body, the more bone mass your body builds to accommodate that use.Considering Wolff's Law, it makes sense that a sedentary lifestyle would result in less dense, less healthy bone.

This study’s authors further explained why sedentary activity leads to bone loss. They noted that previous studies linked sedentary behavior to parathyroid hormone production, which has a negative impact on calcium metabolism.

They also noted that sedentary lifestyles tend to involve more indoor activities, resulting in reduced exposure to sunlight. This limits the body’s ability to produce Vitamin D and disrupts skeletal homeostasis.

Additionally, the study linked decreased physical activity with a higher percentage of body fat. The researchers noted that reducing body fat percentage decreases the risks associated with obesity, including cardiovascular disease, diabetes, and cancer.

Synopsis

The negative impact of sedentary behavior on bone mass can be explained by Wolff's Law, which states that bone adapts to use. The study authors also suggested that causes of bone loss and increased fat could include higher parathyroid hormone production and a lack of Vitamin D production due to sedentary behavior and indoor activities. Reducing body fat percentage decreases the risks associated with obesity, including cardiovascular disease, diabetes, and cancer.

The Relative Importance Of Bone Mineral Density

Bone mineral density is not the sole measure of bone health. It may not even be the most useful. In part, that’s because there are healthy and unhealthy forms of increased BMD.

Bone density does not equate to health or strength. The added density caused by osteoporosis drugs like bisphosphonates happens by warping the bone remodeling process. This pharmaceutical interference prevents the removal of old and damaged bone mass, which makes them denser but less healthy. This causes the negative outcomes associated with use of these drugs, such as atypical femur fracture.

However, bone mineral density added through the body’s response to healthy behaviors like exercise is natural and provides lasting strength and quality. This study examined the impact of physical activity on bone mineral density, so those increases in BMD were natural and likely to help those participants maintain active lives while avoiding fractures.

Synopsis

Bone mineral density (BMD) is not necessarily a good indicator of bone health and strength. BMD added through the use of osteoporosis drugs prevents the removal of old and damaged bone cells. That pharmaceutically altered bone becomes brittle, leading to side effects like atypical femur fracture. BMD added through physical activity uses the full, natural bone remodeling cycle, creating strong and healthy bones.

What This Means To You

Consider how much time you spend engaged in physical activities versus how much time you spend being sedentary. Today’s study clearly demonstrates the value of trading sedentary time for more physical activity.

Take a walk, go for a swim, hit the gym, do some yard work, play with your grandkids – there are many ways to get up and get moving.

Exercise is a necessity for building healthy and strong bones. That's why we created SaveTrainer. SaveTrainer is an online workout platform that provides you with exactly what you need to build an enjoyable, sustainable practice of regular exercise.

Our professional trainers create expertly guided video sessions at every ability level– ensuring that you can start where you’re at and grow at your own pace. Best of all, this resource is available anytime, anywhere.

The results are clear– get moving so you can keep moving. Stronger bones and a healthier life are waiting for you.

References

¹ https://www.nature.com/articles/s41598-023-35742-z