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Environmental Factors For Fatigue And Injury In Ultra-Endurance Sports
Published in Youlian Hong, Routledge Handbook of Ergonomics in Sport and Exercise, 2013
Another aspect of the heat in ultra-endurance performance is the higher prevalence of exercise-associated hyponatremia (Hoffman et al., 2012; Lebus et al., 2010). In the ‘161 km Western States Endurance Run’ in the USA held in rather hot conditions, the prevalence of exercise-associated hyponatremia was reported to be at 30 per cent (Hoffman et al., 2012) and 51 per cent (Lebus et al., 2010). In the study of Lebus et al. (2010), the environmental temperature ranged from 12.2°C to 37.6°C. However, the duration of the ultra-endurance race might also increase the risk for exercise-associated hyponatremia. In a Triple Iron ultratriathlon covering 11.4 km swimming, 540 km cycling and 124.4 km running, the prevalence of exercise-associated hyponatremia was at 26 per cent (Rüst et al., 2012). Apart from heat and duration, cold might also increase the risk for exercise-associated hyponatremia. In ultraendurance swimmers participating in the ‘Marathon-Swim’ in Lake Zurich, Switzerland, covering a distance of 26.4 km, two men (8 per cent) and four women (36 per cent) developed exercise-associated hyponatremia where one woman was symptomatic with plasma sodium (Na) of 127 mmol.L−1 (Wagner et al., 2012). Apart from the cold water, an increased fluid intake due to swallowing water in the lake might have occurred in these athletes. Generally, however, the prevalence of exercise-associated hyponatremia is not higher in ultra-endurance athletes (Knechtle et al., 2011a).
Oxidative stress and adverse cardiovascular effects among professional divers in Egypt
Published in Journal of Occupational and Environmental Hygiene, 2023
Hanie Salah, Ragaa M. El-Gazzar, Ekram W. Abd El-Wahab, Fahmy Charl
In this study, mean serum electrolyte (Ca+, Na+, and K+) levels among the two groups were within normal reference values, although higher levels of Ca+ and lower levels of Na+ were observed in the professional divers compared to the seafarers. A recent study showed that high blood Ca+ levels may increase arterial wall stiffness and subsequently the 10-year CVD risk as assessed by the Framingham score (Park and Lee 2019), which might represent another factor that can lead to increase in the CVD risk. Indeed, hyponatremia may be attributed to repeated physical activity associated with diving and the physical effects of diving, which agree with the findings of Luhker et al. (2017) and Rosner and Kirven (2007) that identified exercise-associated hyponatremia and disturbed acid–base homeostasis after sustained physical exertion during athletic events.
Fluid and electrolyte balance considerations for female athletes
Published in European Journal of Sport Science, 2022
Paola Rodriguez-Giustiniani, Nidia Rodriguez-Sanchez, Stuart D.R. Galloway
Altering the threshold for AVP release could lead to inappropriately high AVP concentration, and may contribute to the onset of hyponatremia, and damaging consequences in the brain (Siegel et al., 2007; Speedy, Noakes, & Schneider, 2001; Verbalis, 2003). Since greater water retention from over-drinking or excessive sodium loss through sweating contribute to exercise associated hyponatremia (EAH), Stachenfeld and Taylor (2009) examined whether sex hormones could influence body water and sodium regulation in women at high risk of EAH during endurance exercise. Their study revealed that more fluid was retained, and more sodium lost, when both oestradiol and progesterone were elevated. The authors suggested that when oestrogen and progesterone were both elevated (e.g. the luteal phase of the menstrual cycle) the monitoring of fluid and electrolyte balance in long duration endurance sports is of particular importance, particularly in women susceptible to symptomatic hyponatremia. It is important to emphasise that women who were most susceptible to EAH had lower body mass which could have exaggerated the impact of excessive water loads and sodium loss during exercise (Stachenfeld & Taylor, 2009).
Considerations for ultra-endurance activities: part 2 – hydration
Published in Research in Sports Medicine, 2019
Martin D. Hoffman, Trent Stellingwerff, Ricardo J.S. Costa
These two compilation papers also demonstrated that exercise-associated hyponatremia (EAH) occurred in an average of 7% (Noakes et al., 2005) and 15% (Hoffman et al., 2013) of the cases, and can be present in association with hyperhydration, euhydration and hypovolemia. However, the symptomatic cases of EAH seem to occur virtually exclusively when there has been a gain in body mass or inadequate loss that is consistent with hyperhydration (Hoffman, Stuempfle, Sullivan, & Weiss, 2015a; Noakes et al., 2005). Indeed, hyperhydration is the primary risk for the development of symptomatic EAH and should be avoided in order to prevent potential health consequences from this condition (Hew-Butler et al., 2015).