Avoiding Bone-Headed Activities for Your Bones

According to the National Osteoporosis Foundation (NOF), about 10 million people in the US have osteoporosis.  The NOF says that those with the greatest risk are above 50 years of age, female (especially post-menopausal), have a family history of the condition, feature thin and small frames, and have experienced skeletal issues as adults (broken bones or decreased height)   Exercise is said to make bones stronger, but what exactly do people mean by that?  Are all methods of exercise smart choices for skeletal health?  For the methods that do work, do they increase bone density throughout the body or just in some areas?

Improving Bone Density 

Use it or lose it.  That seems to be the case with bones: lack of movement accelerates the rate of loss.  Studies analyzing those on bed rest and astronauts coming back from space clearly illustrate this.  Being sedentary is a terrible option for your bones.

Swimming and water aerobics classes are common selections for seniors who are looking to improve bone density.  Swimming is a logical choice for its lower level of impact, but that's where the skeletal benefits end.  It is missing one major, positive influence: GRAVITY!  Just like astronauts in space, swimming alleviates bone-compressing forces, which is likely why studies show it to have basically no effect on improving bone density or slowing down osteoporosis (read here and here).

In the short term, running and sports such as soccer and tennis can improve bone density in the lower body, specifically the hip, thigh, and heel (as shown here and here).  However, they offer little to no benefit for the bones of the upper body and often lead to serious long-term injury because of their high impact natures.

In terms of reversing age-related bone density loss, strength training offers the most effective and most thorough method.  Bone density in the forearm, thigh, hip, and lumbar spine has been shown to improve via studies on strength training (see here, here, and here).  This occurs through two mechanisms.  First, compound exercises (where several joints are involved), such as a leg press or chest press, bring about a force that causes the bones involved to bend slightly.  The result of these slight bends is to increase the deposit of calcium in the bones.  Second, strength training exercises increase bone density at the point where the tendon (of the muscle used) attaches to the bone.  For example, your quadriceps' tendon attaches to a bump (called the "tibial tuberosity") that's a few inches below your knee cap.  When you train your quads, the body responds by increasing bone density at that bump.  

My Recommendations

 In closing, if you're building a routine to improve bone density, this is what I suggest:

1. Strength train twice a week.  Use compound exercises such as the leg press (pictured above), chest press, compound row, pull-ups, and overhead press.  Use weights that you find challenging from the start of the exercise and that will bring you to complete fatigue in less than 90 seconds (one study found bone density to improve only when heavier weights are lifted).
2. If you are sedentary between strength training workouts, go for walks.  Walking won't reverse the loss of bone density, but it may slow down the rate and is a low impact activity.
3. Finally, adjust your diet.  Dr. Bill Davis recommends vitamin D, K, magnesium, and potassium salts as part of his osteoporosis treatment plan (keep in mind that osteoporosis is a lack of calcium depositing in the bone, not a lack of calcium).