More Bone -- and Less Fat -- Through Exercise

Posted by: Dr. Mercola | February 23 2011

Recent research shows that exercise can keep your bone marrow from turning into fat. Bone marrow cells called mesenchymal stem cells transform into either bone cells, fat cells or occasionally other cells when they receive certain molecular signals. Because of this, they determine the strength and quality of bone; the more fat in the marrow, the less bone.

But studies show that when mesenchymal stem cells are stimulated through exercise, more of them turn into bone. Early research shows that the best results come from workouts in several sessions throughout the day.

According to the New York Times:

"Many questions remain, of course ... Still, one lesson is indisputable. Don't sit still more than you need to ... and don't let your children loll about either."

Sources:
  New York Times February 1, 2011

  Journal of Biomechanics December 3, 2010

This intriguing new research shows, essentially, that the more you exercise, the more you can determine the fate of your bone marrow stem cells, triggering them to turn into beneficial bone cells rather than fat cells. You only get one shot at this, as once your stem cells differentiate into a specific type of cell, that's what they stay for the rest of your life.

Exercise Encourages Stem Cells to Turn Into Bone, Not Fat

In an animal study, when mesenchymal stem cells found in bone marrow were stimulated with mechanical vibration meant to simulate exercise, they were more likely to turn into bone cells. What's more, this was true even though the cells were sitting in what the researchers called a "sweet soup" of extra insulin and other substances that would normally make the cells turn into fat cells.

As the New York Times reported, research has also shown that the amount of fat in your bone marrow is inversely related to the amount of bone; in other words, if more of your bone marrow stem cells turn into fat, it means you'll have less bone.

This is a powerful example of how deeply regular exercise can impact your health, right down to the marrow of your bones, to give you improved strength and bone quality. But to get the benefits, you've got to make exercise a part of your regular routine, for life. Exercising for a day here and there once every couple of months will not give you the benefits you're after.

More Support for Acceleration Training?

Interestingly, the study used "mechanical vibrations" to simulate exercise, and this may have been similar to the impacts of whole body vibration, or acceleration training, using a specially designed vibration platform.

According to Newton's second law of thermodynamics, which you might recall from high school physics class:

Force = Mass X Acceleration

Normally we are only using the acceleration due to the force of gravity (1G), and the only way we vary the force in exercise is to increase the weight. However, if you examine the equation you can easily see that you can increase the force by increasing acceleration by increasing the G force to 2 or more.

Whole body vibration platforms work by having a plate that is driven by a motor to rapidly move the exercise platform up and down several millimeters typically between 30 and 50 times per second. The more rapidly the plate displaces, the higher the G forces. Some machines will reach G forces of 8, or eight times the force of gravity.

In one study by Medical College of Georgia researchers, using vibration therapy 30 minutes daily for 12 weeks improved bone density in mice, a finding that adds support for their use in humans, especially the elderly.

It's thought that the vibrations prompt movement of the cell nucleus, which may trigger the release of osteoblasts to build bone. Previous studies have also found that acceleration training increases bone density in the hip and inhibits bone loss in the spine and hip areas.

Since acceleration training is accomplished with very little stress to your joints, tendons and ligaments -- essentially you stand or perform slow specific movements on a vibrating platform -- it can be a very good therapy regimen if you've suffered injuries, if you're elderly, or if you have disease conditions such as arthritis, fibromyalgia or multiple sclerosis, which would normally limit your fitness program.

How Else Does Exercise Build Your Bones?

If you want strong, healthy bones, regular exercise, including weight-bearing exercises like strength training, is essential. Remember, bone-building is a dynamic process, so you want to make sure you exert enough force on your bones to stimulate your osteoblasts to build new bone.

Further, bone is living tissue that requires regular physical activity in order to renew and rebuild itself, so you should make exercise a lifelong commitment.

Peak bone mass is achieved in adulthood and then begins a slow decline, but exercise can help you to maintain healthy bone mass as you get older. Weight-bearing exercise is actually one of the most effective remedies against osteoporosis, as your bones are very porous and soft, and as you get older your bones can easily become less dense and hence, more brittle -- especially if you are inactive.

Rebounding on a trampoline can also be very useful and provide some of the benefits of acceleration training.  Resistance training can also combat this effect because as you put more tension on your muscles it puts more pressure on your bones, which then respond by continuously creating fresh, new bone.

In addition, as you build more muscle, and make the muscle that you already have stronger, you also put more constant pressure on your bones. 

A good weight-bearing exercise to incorporate into your routine (depending on your current level of fitness, of course) is a walking lunge, as it helps build bone density in your hips, even without any additional weights.

Ideally, though, your fitness program should be comprehensive, providing the necessary weight-bearing activities for bone health while also improving your cardiovascular fitness and fat-burning capabilities with high-intensity "peak 8" exercises.

During the 'peak exercises,' you raise your heart rate up to your anaerobic threshold for 20 to 30 seconds, followed by a 90-second recovery period. You repeat this cycle for a total of eight repetitions.

For a more complete, in-depth explanation of my peak fitness regimen, please review this recent article. Implementing peak fitness -- with its array of weight-bearing exercises for bone health and peak 8 exercises for disease prevention, fat loss and more -- may be one of the best lifestyle changes you could ever make!