Changes of ROS during a Two-day Ultra-marathon Race

Abstract

To assess oxidative stress (OS) induced by endurance exercise, concentrations of serum reactive oxygen species (ROS) were determined in 70 Japanese male amateur runners completing a two-day ultra-marathon race. Serum ROS levels were analyzed at three time points: before the race (baseline), after the 1st day race (mid-race), and after the 2nd day race (goal) (post-race). The means (SE) of ROS were 151.4(3.7) (U. CARR.), 168.7(4.4), and 156.8(4.4), respectively. Significant positive trends were noted between age and serum ROS concentrations at the three race points (p<0.05 for all). After adjusting for age, BMI and average monthly running distance, the baseline serum ROS concentrations were positively associated with completion times of the first-day race, in particular (p<0.05), suggesting that the concentrations may predict physical performance. The ROS production increased at mid-race (p<0.05), but the levels returned to baseline levels at post-race, indicating that an antioxidant defense system may develop post-race to reduce OS.

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“…A higher concentration of TBARS before racing was considered indicative of pre-existing oxidative stress and was associated with reduced likelihood of completing the race. Although TBARS have been associated with race finishing time in human ultramarathon runners (Hattori et al 2009), in the current study this biomarker was not significantly correlated with racing speed (Holbrook et al 2010). Additionally, higher basal concentrations of inflammatory markers (TNFa) and lower basal concentrations of anti-inflammatory markers (a-melanocyte-stimulating hormone) in endurance horses were associated with lesser performance (Holbrook et al 2010).…”

“…A higher concentration of TBARS before racing was considered indicative of pre‐existing oxidative stress and was associated with reduced likelihood of completing the race. Although TBARS have been associated with race finishing time in human ultramarathon runners (Hattori et al . 2009), in the current study this biomarker was not significantly correlated with racing speed (Holbrook et al .…”

Neuroendocrine and non‐neuroendocrine markers of inflammation associated with performance in endurance horses

“…Our findings are similar to results from a recent study in man competing in a 2 day marathon. Horses in our study that successfully completed the 80 mile race started with significantly lower TBARS, while in the aforementioned study, finish time was correlated with prerace TBARS in man competing in an ultramarathon (Hattori et al . 2009).…”

“…2009). In addition, baseline oxidant status correlates with completion times in ultra‐marathon runners (Hattori et al . 2009).…”

“…Recently, the relationship of antioxidant status to performance in human endurance athletes was supported by studies demonstrating reduced reactive oxygen species (ROS) production after a treadmill test in runners with higher aerobic fitness (Falone et al 2009). In addition, baseline oxidant status correlates with completion times in ultra-marathon runners (Hattori et al 2009). Scientific evidence associating performance with other inflammatory mediators in athletes is lacking, yet recent studies document reduced physical performance in elderly patients with chronic inflammation, while others confirm this association in people regardless of age, sex or disease status (McDermott et al 2005;Brinkley et al 2009).…”