Bone remodeling is the process in which osteoclasts break down bone and osteoblasts build it back up (Tortora and Derrickson 2012). With increased use, the bone is made stronger. With decreased use, the bone is made weaker. For example, when bones are subjected to extended periods of time without stress they lose density. This is because the body always tries to maintain homeostasis and doesn’t want to function at a higher level than it has to. Conversely, when the bone is stressed, it becomes stronger. One of several aspects of bone remodeling is the repair of damage to bone. With each repair the bone becomes thicker and stronger at the point of damage. This damage does not always have to be a traumatic break. It can be micro trauma caused by everyday activity.

Runners are one portion of the population that relies heavily on bone remodeling to enjoy their sport. Runners put tremendous stress on their bones and muscles as they run. For some runners, they break down their bones at a faster rate than they can be repaired. When this happens, the result is a stress fracture (Lovett 2008).  He lists four criteria from sports scientist Tim Noakes that are useful in deciding whether or not you have a stress fracture. “1. It comes on without warning 2. There is no other obvious explanation 3. You can sometimes find a spot on the bone so tender that pressing on it will produce a pain he describes as “exquisite” or “nauseating”; and 4. It fails the hop test, which means it hurts if you hop on the injured leg.” He lists several risk factors for stress fractures. They are, increasing training volume too much too soon, insufficient muscularity. He further elaborates saying that muscles act as shock absorbers and those with more developed muscles put less stress on their bones.

This is useful information because a surprising amount of runners have to deal with stress fractures. Knowledge is power in preventing injuries. By making sure that they maintain muscular development and not over training runners can reduce the chance of getting stress fractures.

Literature Cited:

Tortora G.J. and B. Derrickson. 2012.  Principles of Anatomy and Physiology.  13^th ed., John Wiley and Sons.

Lovett, R.A.  “Owner’s Manual: Is it a stress fracture?” Running Times. March 2008. http://www.runningtimes.com/Article.aspx?ArticleID=12894&PageNum=&CategoryID=

Athletes are always looking to gain an edge over their opponents in competition. One way they do this, in addition to proper training is nutrition. Two main goals of sports nutrition are to improve performance during the event and enhance recovery after the event.  Before an event, athletes often load up on carbohydrates believing that it will give them increased access to muscle glycogen and improve performance.  After the event is completed, the athlete’s goal nutritionally is to replenish glycogen stores that were used and enhance repair of whatever damage sustained during the event. Athletes traditionally do this through carbohydrate consumption. Until recently, protein has taken a back seat to carbohydrate concerns in endurance sports nutrition.

In The Paleo Diet for Athletes, Loren Cordain and Joe Friel adapt a low carbohydrate moderate protein high fat diet to one that is most beneficial to athletes. They meld traditional sports nutrition with their variant of a low carb diet. The paleo diet is very good for general health and recovery but it is not the most effective approach for replenishing glycogen stores. This is due to the low carbohydrate intake. Their answer to this problem is to strategically consume carbohydrates and protein at specific times to maximize performance and recovery. This is different from the general approach in that it is more specific in timing. A typical endurance athlete’s nutritional regimen advocates eating carbohydrates in high amounts all day. The authors recommend a low carbohydrate diet except at certain times in relation to athletic events. The authors divide their approach into 5 stages. The book is further organized to address specific challenges faced by events of different lengths.

This book is useful because it can help athletes of all abilities to maximize their performance. Although useful to elite athletes, I think it is particularly useful to weekend warriors and less serious athletes. Proper nutrition can allow them to be competitive with less time training. Of particular interest in the book are the sections on long endurance events like iron man triathlons or ultra marathons.