Ultra-endurance exercise: unanswered questions in redox biology and immunology

Abstract

Ultra-endurance races are extreme exercise events that can take place over large parts of a day, several consecutive days or over weeks and months interspersed by periods of rest and recovery. Since the first ultra-endurance races in the late 1970s, around 1000 races are now held worldwide each year, and more than 100000 people take part. Although these athletes appear to be fit and healthy, there have been occasional reports of severe complications following ultra-endurance exercise. Thus there is concern that repeated extreme exercise events could have deleterious effects on health, which might be brought about by the high levels of ROS (reactive oxygen species) produced during exercise. Studies that have examined biomarkers of oxidative damage following ultra-endurance exercise have found measurements to be elevated for several days, which has usually been interpreted to reflect increased ROS production. Levels of the antioxidant molecule GSH (reduced glutathione) are depleted for 1 month or longer following ultra-endurance exercise, suggesting an impaired capacity to cope with ROS. The present paper summarizes studies that have examined the oxidative footprint of ultra-endurance exercise in light of current thinking in redox biology and the possible health implications of such extreme exercise.

High Volume Exercise Training in Older Athletes Influences Inflammatory and Redox Responses to Acute Exercise

“…Aging is associated with a progressive change in most aspects of physiology, including impairments to the cardiovascular, musculoskeletal, immune and endocrine systems (Lopez-Otin, Blasco, Partridge, Serrano, & Kroemer, 2013). Although many processes implicated in aging and disease are improved, or at least limited, by moderate to high volumes of exercise, evidence is beginning to show that some aging processes might be accelerated by very high volumes of exercise (Simpson et al, 2016;Turner, 2016;Turner, Bennett, Bosch, Griffiths, & Aldred, 2014). For example, it is possible that the prolonged inflammatory profile seen during periods of very high volume training or following extreme exercise (Turner et al, 2014), which in middle-aged or elderly individuals, would be superimposed on the age-associated increase in inflammation, could exacerbate the decline in immune function known as "immunosenescence" (Simpson et al, 2016;Turner, 2016).…”

Acute Effects of Triathlon Race on Oxidative Stress Biomarkers

“…lipids, proteins, carbohydrates, and nucleic acids) [16,17] in both skeletal muscle and blood [18], is known as oxidative stress (OxS). As widely reported, OxS may result in an inflammatory response by the immune system to protect tissues [12,19,20]. Nonetheless, at appropriate concentration, ROS are known to act as important signaling molecules [21,22].…”

“…Triathlon thereby provides a great opportunity to investigate the effects of multidisciplinary exercises on health, and to this aim, much remains to be done [3]. Long competitions require great power endurance possibly leading to heat stress and dehydration [4,5], muscle injury [6], oxidative stress [7,8], inflammation [9,10], immunologic alterations [11,12], and cardiac remodeling [13].…”

Inkontinenz bei Leistungssportlerinnen

“…Im Bereich extremer körperlicher Belastungen, wie sie im Leistungssport zu finden sind, können die positiven Effekte des Trainings aber auch ins Gegenteil umschlagen. Zu den bekannteren Beispielen zählen Ausdauersportarten im "Long-" und "Ultra"bereich, die mit Kardiomyopathien korrelieren [1] und extrem erhöhte Werte an schädigenden Stoffwechselprodukten (reaktive Sauerstoffspezies, ROS) aufzeigen [2].…”