LeBron and Exercise-Associated Muscle Cramping

Does this count as “Old School”? LeBron James, in his first incarnation as a Cleveland Cavalier (photo: Dave Hogg, Wikimedia)

Game 2 of the NBA finals is this weekend, and I’m sure the Miami Heat (despite their nickname) are hoping the air conditioning works.  In truth, I think most of us are hoping that we witness a straight up basketball affair determined more by athletic skill and less by Exercise-Associated Muscle Cramping (EAMC).

If you need a primer to know what I’m talking about, here’s a brief rundown of Game 1 and LeBron’s EAMC. 

‘Most of us’?  I truly have no horse in this race (speaking of that….I most definitely am rooting for California Chrome to bring home the Triple Crown later today), but outside of Texas, it seems that most of the country may be leaning toward the Heat.  At least that’s what ‘Big Data’ would suggest:  check out this great, data-driven map from the New York Times showing the breakdown of team allegiances across the United States.

Truly though, aside perhaps from a pocket deep in the heart of Texas (who may want victory, no matter what!), I think most fans of the NBA would rather see the outcome of the games determined by the players and not by a lack of AC.

As a team physician, like many of you, I have had–along with my Athletic Trainers–to deal with plenty of muscle cramping in my career.  Here in the States, I find it occurs most often in the very beginning of football season:  during August pre-season, or the early September games that may be played in temperatures approaching 90 degrees.  It seems the combination of relative deconditioning, environmental conditions, and plain foolishness (my adolescent athletes frequently forget to stay hydrated, despite constant reminders to do the same)  gives rise to any number of trips on to the field to assist a player downed with quad or abdominal cramps.  At some levels of the game, to circumvent that inability to maintain adequate oral hydration during a game, teams will turn to pre-game intravenous hydration, as has been discussed in literature published in this journal and blog.

Then again, perhaps there are other issues altogether different than these potential risk factors that give risk to EAMC. Despite the high incidence, the etiology of EAMC continues to be debated.

Yes, I am a believer in the powers of pickle juice, but EAMC remains a puzzle to me and others.  And so I turned to the CJSM website  this morning for guidance and found a great 2013 study:  Collagen genes and exercise-associated muscle cramping, from a group of South African authors.  I especially appreciated this article for its contribution to my basic science knowledge:  I learned so much about the biology behind EAMC.  I encourage you all, clinicians and non-clinicians, to check it out.

The authors begin the paper with an excellent overview of various hypotheses of EAMC, ranging from electrolyte depletion to altered neuromuscular control. They then explored the literature that points to the possibility that EAMC may be associated with a genetic predisposition to musculoskeletal soft tissue injury. Specifically, their research hypothesis was that “variants within collagen genes that code for components of the musculoskeletal system would increase susceptibility to EAMC.”  To test this, the authors conducted a ‘retrospective case-control genetic association study’. Read more of this post