Protect Your Bones: GET STRONG

Background

When any given structure is overloaded, that structure will (eventually) fail.

Our bodies are no different: when they are repeatedly overloaded, failure and injury will ensue.

Every time we take a step or run, a ‘load’ is placed upon our bones, joints, muscles and tendons. If the load of gravity pulling on us is repeatedly greater than what our bodies can handle, pain and injury will result.

The primary means by which we counteract the force of gravity when we walk or run is through muscular contraction. It makes intuitive sense that if our muscles are weak or tired, gravity will slowly ‘win’ and our tissues will start to become overloaded.

This intuition was examined in research study cited below.

Study: “The effect of muscle fatigue on in vivo tibial strains.” Milgrom et. al, Journal of Biomechanics, 2007.

In this study, 4 individuals had surgically implanted devices placed in their tibias (shin bones). These devices were known as ‘strain gauges’ and were able to measure the amount and rate of strain placed upon the tibia.

The tibial (shin) strain amounts and rates were calculated before and after exercise intended to fatigue the muscles (a 1.25 mile run and 18 mile hike).

The strength of the calf muscle was also measured pre and post run/hike.

Not surprisingly (it was 18 miles!) the strength of the calf muscle was significantly reduced after the hike.

Also not unsurprisingly (but enlightening nonetheless), the amount and rate of strain in the tibia (shin bone) was significantly increased in the post-hike state.

The authors conclude, “The present study supports the hypothesis that the fatigue state increases bone strains.”

Application

The take home message of this study is very simple: when our muscles are weak or tired, our bones experience greater stress (or strain).

As noted above (and at several points in the discussion in this study), when our bones (or tendons, ligaments, etc.) are perpetually overloaded with stress, pain and injury will follow.

The solution? Either decrease the stress to your tissues by walking/running/moving less (not an attractive option), or increase your ability to handle the stresses of life by increasing your strength and endurance levels (a MUCH preferred path).

If the stresses of life are overloading your body and you would like professional assistance in getting stronger so that you can live a more active and pain free life, please do not hesitate to reach out to me.

Click to schedule an appointment or contact me at 434-872-1850 (or RenewedLifePhysicalTherapy@gmail.com).

References

https://pubmed.ncbi.nlm.nih.gov/16682046/#:~:text=The%20fatigue%20state%20increases%20bone,in%20the%20stress%20fracture%20etiology.