Good answer Mahesh, I agree. What about HRV with CK or LDH? Do you have any experience with these? We are correlated LF/HF ratios with these. Have you ever used LF/HF ratios (supine and tilt and its relation) as biomarker?

Thanks.

How do you define "fatigue"? without a clear definition it is difficult to give you a proper answer. Most research shows that, at present, there are no physiological or biochemical measures that are better than self-reports to monitor OR/OT and recovery. So I suggest you save money and collect properly and in a systematic manner valid self-reports.

Thanks Samuele for your answer.

CK and others biomarkers for peripheral muscle fatigue (BPMFs)  are most used in professional soccer teams from many countries. Argentina and Brazil for instance. So, my question was related more to muscle fatigue. 

I think that a more appropriate definition of muscle fatigue for any population could be: “Any decline in muscle performance associated with muscle activity at the original intensity” (Simonson 1976; Bigland-Ritchie 1986; Bogdanis 2012).

 There are so many controverses in the literature, because of this I wanted an opinion from others with more experience in this field.  

We keep on working with HRV measures and we've just sent a manuscript titled "Autonomic activity and heart rate variability as a biomarker of training load in professional soccer players during a competitive season"where HRV parameters were compared in professional soccer players identified as either in ‘muscular fatigue’ or in ‘no-fatigue’ state under ‘real life’ conditions.

You can find a similar study from Schmitt, where HRV parameters were compared in elite athletes identified as either in ‘fatigue’ or in ‘no-fatigue’ state. The states of fatigue were identified according to the scoring at the QSFMS, which was fulfilled after the RR interval recording procedure. 

Reference: Schmitt, L, Regnard J, Desmarets M, et al. Fatigue shifts and scatters heart rate variability in elite endurance athletes. PloSOne 2013;12;8(8): e71588-Doi: 10.1371/journal.pone.0071588.eCollection [published Online First: August 12, 2013].

Regards,

JV

Thanks Mahesh for your answer. We started to work with CK, LDH and amonia in 2009 with Argentine Football National Team. Same time we measured HRV. We had our own blood biomarker analyzer (Johnson & Johnson). We  found interesting information. So, we kept on working with these parameters (we added Testosterone/Cortisol ratio) during 2011-2012 in Dubai. We didn't have analyzer and we worked with a local hospital laboratory. I turned to be difficult and it was not practical. We need to get more samples but we believe in this method to quantify muscle fatigue in the players, specifically before games.

Dear  Mahesh Kumar,

A diagnosis of the muscle fatigue in field studies in athletes top class is a complex problem. Transferring the results of controlled studies to the practice of sport often leads to incorrect conclusions. As a rule, experienced coaches will determine fatigue in athlete  much faster and more accurately than any biochemical test. Therefore, the diagnosis of fatigue should be replaced by a prediction of fatigue. Muscle fatigue, in the evolutionary aspect, is the accumulation of sub-threshold disorders of oxygen delivery to the muscle cell. This problem is  solved by the evaluation of the blood acid-base balance. For example. In the resting state - the compensated metabolic acidosis condition. In the state of physical activity and the recovery phase, the uncompensated metabolic acidosis. In particular, the ratio of base excess (BE) to blood lactate concentration [La].

Best regards,

Oleg

Colleagues: look at this conclusion from this article in press (review from a colleague Paola Brancaccio, she appears in RG)

"Muscle damage may occur following physiological and pathological conditions. Blood analysis and urinalysis provide a composite picture of muscle status and a better estimation of muscle stress. In addition, the evaluation of oxidative stress by markers of protein and lipid oxidation may be useful to better assess and quantify muscle stress following exercise".

Paola Brancaccio, Giuseppe Lippi and Nicola Maffull. Biochemical markers of muscular damage. Clin Chem Lab Med 2010;48(6):xxx-xxx 􏱨 2010 by Walter de Gruyter • Berlin • New York. DOI 10.1515/CCLM.2010.179

Dear Javier,

we are collecting HRV, CK and cholesterol data of elite hungarian soccer players for cca. 4-5 yrs. We found correlations between these data. To be more shure we measured also the alpha and theta brain waves of those players, and from the the frequency levels there were shown fatigue, too. 

If you are interested in, I can write you the details, how and which data were collected.

Please be so kind to inform me when your manuscript will turn to a published article.

Best regards,

Edith Dömötör

OK, Edith, I will. Please, I'm interested on your data. 

Thanks.

Regards, JV

I'll back home in 2 weeks, and then I'll send you further information.

Regards,

Edit

Dear Javier,

I've got today this article of serbian scientists. Perhaps it may interest you (see attachment).

Regards,

Edit Dömötör

Very interesting! Thanks.

Hi!

We  was trying to find out the relationship between the testosterone/kortisol and HRV. There was a relationship but very weak. Probably because the group wasn't big enough. the study was carried out with elite XC skiers.

Regards

Hi Irina

Big trouble to get samples with a considerable number of athletes. They are training and going to competitions constantly. We've found a good situation with professional soccer players, because you have a team, they train and play all together.

Do you evaluate olympic athletes? Did you check athletes from another sports?

Thanks.

JV

Hi Javier

Yes we also evaluated speed skaters and biathlon  athletes  from the national team.  Yes the problem is that olympic team is not too big to make statistical analyses but for coaches it was very useful.

Kind regards, Irina

Hi Irina

We are testing Olympic Athletes in the High Performance Center. In pre season and during competitive period. Dr Lentini has recently evaluated a lot of people in Youth Olympic Games, with Omega Wave Technology. There were considerable number of cases. We will see in the next weeks the results. Thanks. 

JV

We are getting some conclusions from non functional OR in a case study (professional soccer player): HRV, CK, LDH. Control group: 7 players from same team but normal performance during season. Article coming soon….  

As it was written in the last message, a paper titled "Cardiac autonomic imbalance in a nonfunctional overreached professional soccer player (case study)" was presented in FIFA Symposium in London: "Football Strategies for Player Care".

It can be downloaded from the RG profile as "Conference Paper".

Thanks.