Friday, August 24, 2007

are you training too much?

This study was trying to identify clear indicators for overtraining - i.e. things that could be measured to give an objective indication that an athlete had overtrained. This is interesting in itself, but it is also interesting to note the effects of over training - there is a reduction in antioxidant levels in the body. This is generally thought to be a bad thing. Antioxidants mop up free radicals which otherwise would cause oxidation - damage to cells.

If over training is leading to oxidative damage to the body it could explain some of the problems that seem to be associated with endurance exercise. (Just to be clear though this article is about resistance training not endurance is just that I think endurance athletes are generally chronically over trained.)

Oxidative stress biomarkers responses to physical overtraining: Implications for diagnosis.
Margonis K, Fatouros IG, Jamurtas AZ, Nikolaidis MG, Douroudos I, Chatzinikolaou A, Mitrakou A, Mastorakos G, Papassotiriou I, Taxildaris K, Kouretas D.

Department of Physical Education and Sports Science, Democritus University of Thrace, Komotini 69100, Greece.

Overtraining syndrome is characterized by declining performance and transient inflammation following periods of severe training with major health implications for the athletes. Currently, there is no single diagnostic marker for overtraining. The present investigation examined the responses of oxidative stress biomarkers to a resistance training protocol of progressively increased and decreased volume/intensity.

Twelve males (21.3+/-2.3 years) participated in a 12-week resistance training consisting of five 3-week periods (T1, 2 tones/week; T2, 8 tones/week; T3, 14 tones/week; T4, 2 tones/week), followed by a 3-week period of complete rest. Blood/urine samples were collected at baseline and 96 h following the last training session of each period. Performance (strength, power, jumping ability) increased after T2 and declined thereafter, indicating an overtraining response. Overtraining (T3) induced sustained leukocytosis, an increase of urinary isoprostanes (7-fold), TBARS (56%), protein carbonyls (73%), catalase (96%), glutathione peroxidase, and oxidized glutathione (GSSG) (25%) and a decline of reduced glutathione (GSH) (31%), GSH/GSSG (56%), and total antioxidant capacity. Isoprostanes and GSH/GSSG were highly (r=0.764-0.911) correlated with performance drop and training volume increase. In conclusion, overtraining induces a marked response of oxidative stress biomarkers which, in some cases, was proportional to training load, suggesting that they may serve as a tool for overtraining diagnosis.

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