Effect of a Multistage Ultraendurance Triathlon on Aldosterone, Vasopressin, Extracellular Water and Urine Electrolytes

Abstract

Prolonged endurance exercise over several days induces increase in extracellular water (ECW). We aimed to investigate an association between the increase in ECW and the change in aldosterone and vasopressin in a multistage ultraendurance triathlon, the 'World Challenge Deca Iron Triathlon' with 10 Ironman triathlons within 10 days. Before and after each Ironman, body mass, ECW, urinary [Na(+)], urinary [K(+)], urinary specific gravity, urinary osmolality and aldosterone and vasopressin in plasma were measured. The 11 finishers completed the total distance of 38 km swimming, 1800 km cycling and 422 km running within 145.5 (18.8) hours and 25 (22) minutes. ECW increased by 0.9 (1.1) L from 14.6 (1.5) L prerace to 15.5 (1.9) L postrace (P < 0.0001). Aldosterone increased from 70.8 (104.5) pg/mL to 102.6 (104.6) pg/mL (P = 0.033); vasopressin remained unchanged. The increase in ECW was related neither to postrace aldosterone nor to postrace vasopressin. In conclusion, ECW and aldosterone increased after this multistage ultraendurance triathlon, but vasopressin did not. The increase in ECW and the increase in aldosterone were not associated.

33 Ironman triathlons in 33 days–a case study

“…This is comparable to the 1.8 ± 2.1 kg loss in body mass of the 23 Deca Iron ultra-triathletes described by Herbst et al ( 2011). A similar result has been reported by Knechtle et al ( 2012a) with a loss of 1.7 ± 2.4 kg body mass in 11 finishers in a Deca Iron ultra-triathlon. In contrast to the Deca Iron ultra-triathletes described in Herbst et al ( 2011) and Knechtle et al ( 2012a) where performance decreased with increasing race duration, the present athlete was able to maintain his performance across the 33 days.…”

“…In addition to the classical Ironman triathlon held as a single stage race, also multi-stage races with consecutive Ironman triathlons held for several days are known (Herbst et al 2011; Knechtle et al 2012a). Actually, the Deca Iron ultra-triathlon covering ten Ironman triathlons within ten days is the most popular multi-stage race (Herbst et al 2011; Knechtle et al 2008a, [b], 2012a).…”

“…Actually, the Deca Iron ultra-triathlon covering ten Ironman triathlons within ten days is the most popular multi-stage race (Herbst et al 2011; Knechtle et al 2008a, [b], 2012a). Recent studies showed that performance for each Ironman triathlon during a Deca Iron ultra-triathlon decreased with increasing duration of the race (Knechtle et al 2012a) where the fastest Ironman was achieved on the first day (Day 1) (Herbst et al 2011; Knechtle et al 2008a) and the slowest on the last day (Day 10) (Herbst et al 2011). …”

“…A Deca Iron ultra-triathlon is a highly selective race and less than 50% of the starters are able to finish (Herbst et al 2011; Knechtle et al 2012a). For the very long ultra-triathlon distances ( i.e.…”

“…Since the first edition of a Deca Iron ultra-triathlon in 2006 in Monterrey, Mexico (Knechtle et al 2008a, 2011), several races of this kind have been held (Herbst et al 2011; Knechtle et al 2008a, [b], 2012a). To date, the edge of human limits in ultra-triathlon was the Double Deca Iron ultra-triathlon covering the total distance of 20 Ironman triathlon races (Lenherr et al 2012; Rüst et al 2014).…”