in cytokines, leptin, and IGF-1 levels in overtrained athletes during a
prolonged recovery phase: A case-control study

R, Uusitalo A, DeRuisseau CK, & Stalay M. Journal of Sports Sciences. Published online 14 Dec 2016. doi:

Take Home Message: Overtrained athletes have abnormal inflammatory
and anabolic responses to exercise, indicating that their body is not
responding to exercise the way that it should.

Rest and recovery is an important
aspect of training that can often be overlooked.  When athletes or clinicians do not allow for
appropriate recovery, this can lead to overtraining syndrome.  Overtraining syndrome is associated with poor
performance and lack of exercise tolerance. 
While we know clinically what the symptoms of over training are (e.g.,
poor performance), it remains less clear what is occurring
pathophysiologically.  Therefore, the
authors of this prospective cohort study assessed biochemical measures of
inflammation, energy metabolism, and growth factors between overtrained and
control athletes, and how these athletes respond to exercise bouts.  Seven overtrained athletes and 10 healthy
control athletes were examined at baseline, 6 months, and 12 months.  Researchers studied blood samples collected
before and immediately post-exercise (maximal cycle ergometer exercise test) for
certain biochemical markers indicative of inflammation, energy metabolism, or
muscle growth.  Researchers also assessed
physiological measurements, including VO2 max, body composition, time to
exhaustion, maximal heart rate, and maximal power output.  During the 12 months, overtrained athletes completed
a lower intensity training program aimed at recovery, while control athletes
continued their normal training routines. 
Only 6 overtrained athletes completed the 6 month evaluation and 4
completed the 12 month session. Body fat percentage was consistently higher in
overtrained athletes in comparison to control athletes.  Biochemically, changes in an inflammatory
mediator (interleukin-6) after exercise correlated to VO2 max changes. Overtrained
athletes consistently had greater pro-inflammatory changes (i.e.,
interleukin-1beta) after exercise while the control athlete did not.  Also, leptin, which relates to energy
metabolism, was consistently lower at rest in overtrained athletes when
compared with control athletes, while an anabolic marker (insulin like growth
factor-1) decreased after exercise in overtrained athletes but not control

These findings are interesting
because it shows that there is a pathophysiologic reason for the clinical
symptoms that we are seeing among overtrained athletes.  Biochemical markers may be an important
objective measure to take into consideration when trying to decide how to treat
an athlete.  Normal responses to exercise
are important for health and performance, but when an athlete is overtrained,
there are abnormal responses being observed. 
It would be interesting to see if the overtrained athletes adhered to
recovery exercise programs better, how long it would take to return to a normal
status.  It would also be interesting to
see if recovery to a normal status would be affected by how long an athlete was
in an overtrained state.  While the study
is limited by its small sample size and large dropout rate it still provides interesting
evidence that “pushing through” training plateaus by training harder could
adversely affect how our body responds to exercise.  Overtrained athletes are actually achieving
worse physiologic outcomes, and have biochemical profiles that are not allowing
their bodies to optimally regulate inflammation and anabolic processes, and
these findings may be exacerbated if the exercise was an impact based activity
as opposed to a cycle test.  Finding an
appropriate balance between training and recovery is critical.  As clinicians, we need to educate our
athletes to listen to how their bodies feel. 
There is a physiologic reason for why they feel that way, and their body
will fail to respond the way they want it to if they continue their training

for Discussion:  What are your thoughts
on training cycles?  Do you have any
other successful clinical measures for identifying and successfully intervening
in over-trained athletes?

Nicole Cattano
by: Jeffrey Driban


The Impact of Pitch Counts and Days of Rest of Performance among Major-League Baseball Pitchers

Joro, R., Uusitalo, A., DeRuisseau, K., & Atalay, M. (2016). Changes in cytokines, leptin, and IGF-1 levels in overtrained athletes during a prolonged recovery phase: A case-control study Journal of Sports Sciences, 1-8 DOI: 10.1080/02640414.2016.1266379