When it comes to exercise, brisk walking and riding a stationary bike are the least likely to strengthen bone. If people really want to bulk up their bones, they should try running instead, according to a report presented at the 66th annual meeting of the American Academy of Orthopaedic Surgeons. In a study of six people, Dr. Charles Milgrom of Hebrew University Medical School in Jerusalem, Israel, measured both the maximum amount of strain on the tibia, the bone in the lower leg commonly known as the shin bone, and the rate of strain, during a variety of recreational activities.

Walking produced a relatively low strain and strain rate, suggesting that the activity was doing little to make bones stronger. Riding a stationary bicycle was even less impressive, and both activities scored well below the bone-strengthening potential of running. In terms of bone strengthening, running exceeded every activity that the researchers tested included using a stepmaster and performing leg presses on a squat machine. Many people most in need of bone strengthening exercises may not be able to run. However, to begin the bone-strengthening process, you don't have to do the activity for long. Thus, if people could run for even 60 seconds, then slow down to a brisk walk, that will give a short blast to the bone and that should be enough to turn bone on.

COMMENT: More evidence to support the high intensity low repetition form of exercise for certain benefits. The issue here is to generate enough force to stimulate forces in the bone that will trigger growth. Running generates 300% more force than walking. I was surprised to find out that such a small time was required to notice a benefit. So, those of you who are over 60, you might want to start a jog, walk program to improve your bone density. Also, don’t forget the vitamin D (sunshine) calcium and natural progesterone. I am still in the process of implementing the high intensity low repetition weight training program. I have been doing 20 minute workouts twice a week for the last month and have been favorably impressed with the approach.