The View from the Classroom

Hopefully you’ve been following my blogs and you’re up to speed on the first two benefits to weight training, but if not, just take a moment and go read parts 1 & 2. 

Today’s blog is about bone density and how weight training can help increase it.  If you’re like me, you’ve heard that before…weight training can help increase bone density, but you’re curious as to how.  I mean how does building muscles help build stronger bones?  Without being too overly scientific, I’m gonna break it down for you.  Read on.

Ok…first a quick lesson on osteoporosis.  Osteoporosis occurs over time when the amount of bone broken down exceeds the amount of bone replaced by new bone cells which in turn leads to a decrease in bone density.  The result…brittle, frail, easily broken bones.  Now, you probably think of old women when you hear or read about osteoporosis.  Truth is, however, it can affect men as well and though my blog is geared towards women, here are a couple of quick facts…of the 10 milliion Americans estimated to have osteoporosis, 2 million are men and about 1 in 5 men will suffer from osteoporosis.  Additionally, osteoporosis can take place at any age and there are typically no symptoms until a fracture occurs.

Women, however, are at greater risk of osteoporosis.  Why?  It’s hormonal (isn’t everything).  Up to the age of 30 the human body builds and stores bone quite efficiently.  After that, bone starts breaking down faster than new bone is formed and that rate of deterioration is accelerated in women after menopause due to the decrease in estrogen production.  Women can lose up to 20% of their bone mass in the 5-7 years following menopause.  WOW.

BUT, there is good news.  Osteoporosis or at least the degree of osteoporosis is highly preventable.  You can do something about it.  The National Osteoporosis Foundation lists 5 factors that will optimize bone health and help prevent osteoporosis.  ALL 5 factors…balanced diet with adequate calcium and vitamin D, WEIGHT BEARING AND RESISTANCE TRAINING EXERCISES, healthy lifestyle with no smoking or excessive alcohol consumption, educating yourself and getting testing/appropriate medication when necessary…are in your control.

So, how does weight-training help bone density?  By putting stress on the bone.  Yep.  It’s that simple.  Muscles are attached to the bones.  When you train a muscle, it puts stress on the bone.  If the stress is great enough, bone growth is stimulated because bone is living tissue that adapts to the amount of stress placed on it.  Bone density decreases when muscle atrophy (wasting away) occurs through inactivity and bone density increases as muscle tissue increases due to the stress on the bone.  Like I said, it adapts.

AND…free weights have been shown to be more effective than machines in osteoporosis prevention.  Why?  More stress is put on the muscle with free weights.  Think about it.  Machines assist and guide you through the exercise .  They don’t allow you to bear the weight against gravity thereby limiting the amount of stress to the bone.  Gravity is a factor when training with free weights.  You’re bearing the weights against gravity using nothing but the muscle you have.  Stress on the muscle is created which in turn stresses the bone and leads to stronger, healthier, more dense bones.

You’ve heard the slogan, "Milk builds strong bones", right?  I have a new one…Weight-training builds strong bones!

This entry was posted on Monday, July 30th, 2007 at 1:19 pm and is filed under The Whys of Weight Training. You can follow any responses to this entry through the RSS 2.0 feed. You can leave a response, or trackback from your own site.