Researchers in the Netherlands have developed a method of diagnosingequine overtraining syndrome by measuring the nocturnal secretion ofgrowth hormones.
The research, conducted at Utrecht University’s Faculty of Veterinary Medicine, could have implications for human medical science.
Overtraining syndrome leads to a reduction in performance despite training levels being maintained or increased.
Utrecht University’s veterinary researchers found that they were able to diagnose overtraining syndrome by measuring growth hormones present in horses’ blood.
It is the first time an effective diagnostic test has been developed for the condition, and it could lead to improvements in the treatment of both horses and humans suffering as the result of over-exercising.
Han van der Kolk (pictured), one of the research team at Utrecht University, said that as there are more than 200 different symptoms of overtraining in humans, a clear diagnostic test based on hormone levels would be valuable.
Outlining the development of his team’s research, Dr van der Kolk said: “From the very beginning of the project in 2003, our veterinarians worked closely with medical Professor Hans Keizer, an expert on sports medicine endocrinology. His ideas on overtraining in human athletes greatly influenced the set up of the project. In humans, growth hormone pulsatility is expected to decrease in association with ageing. Prof Keizer hypothesised that in overtrained human athletes, this decrease in growth hormone pulsatility would occur earlier in life.
“We used a previously validated model for overtraining in standardbreds, characterised by the abolishment of rest days, to study this concept.
“Overtrained standardbred horses indeed showed altered nocturnal growth hormone pulsatility (increased number, but lower peaks). Surprisingly, this altered growth hormone profile in overtrained standardbreds still persisted following four weeks of detraining.”