Temporal changes in thiol-oxidized plasma albumin are associated with recovery from exercise-induced muscle damage after a marathon

Exercise-induced muscle damage (EIMD) can affect athlete performance and is a risk factor for major muscle injury. The temporal profile of thiol-oxidized albumin, a marker of oxidative stress, has shown potential in assessing recovery from EIMD in non-athletically trained participants but not yet in trained participants. Our primary aim was to assess whether there are changes in the level of thiol-oxidized albumin after a marathon in athletically trained participants. Twenty participants completed a marathon and collected daily dried blood spots from 3 days prior to and 7 days after the marathon to measure thiol-oxidized albumin using a novel methodology (OxiDx). Participants were also assessed for indirect markers of EIMD prior to and on days 2 and 5 post-marathon. The level of thiol-oxidized albumin peaked at 2 days and remained elevated until 5 days after the marathon and correlated with indirect measures of EIMD. Furthermore, time of recovery for thiol-oxidized albumin varied between participants, some recovered at 3 days post-marathon whereas others extended beyond 7 days post marathon. Tracking temporal changes in the level of thiol-oxidized albumin has potential to be useful in managing recovery from EIMD in athletes, particularly considering the ease of the OxiDx methodology.