June 2016

Blood, sweat and tears: new cortisol assay developed

In the highly competitive field of elite sport, athletes and their coaches are increasingly turning to science to help them assess physiological status and wellbeing in an attempt to optimise any competitive advantage. Stress biomarkers such as cortisol are often used to monitor and adapt an athlete’s training regime but results must be quick to be effective. Current tests do not provide the immediacy required as they are all laboratory based and require extensive sample processing.

As Brian Cunniffe, of the English Institute of Sport explains, “As the world of sports science changes rapidly, so does expectation from coaches and athletes to understand the training process in greater detail, more reliably and rapidly. Traditionally, most hormonal samples are collected either through venepuncture (blood) or saliva. Samples are then taken back to a laboratory, frozen and analysed a few weeks later. This can represent a cumbersome and inefficient process if we are to provide coaches and athletes with up to date information that informs the training process in the ‘here and now’ rather than the past.”

In collaboration with the English Institute of Sport, LGC has developed a novel assay for both the biologically active ‘free’ cortisol (that is not bound to other serum proteins) and total cortisol. The plate-based assay uses blood samples taken via a pin prick to the finger and was evaluated using athletes at Loughborough University pre- and post-training. It eliminates the need for extensive sample processing and reduces the incubation step to 15 minutes without affecting the assay recovery or reproducibility.

The blood-based test provides real time data for cortisol levels in the field. It uniquely guarantees both ‘free’ and total measurements in the same sample, providing athletes with further information: the percentage of biologically active cortisol, which may in the future provide more robust data on which to base training decisions.

Innovative breakthroughs such as this could help elite athletes refine their training regimes and increase the potential for success. Elite success is known to boost the 'feel-good' factor amongst the UK public and result in increased uptake in sports activities, saving the health service between £1,750 and £6,900 per additional active person, and contributing further to the UK economy.

Furthermore, this assay has the potential to provide additional future benefits in other areas, such as diagnosing and monitoring illnesses where stress is a surrogate marker of health status, improving quality of life and contributing further to the UK economy.