Good hydration is particularly difficult during long endurance competitions such as triathlons, as you can only drink a limited amount during exercise. At the same time, the body loses large amounts of water and minerals, which can lead to exhaustion, inflammatory reactions and delayed regeneration.
This study investigated whether purified seawater is a useful alternative to normal water or saline solution as a hydration strategy for triathletes. The athletes completed several triathlon competitions and drank either seawater, a saline comparative solution or normal water.
The key result: seawater did not lead to a direct increase in performance, but did influence important messenger substances involved in regeneration and metabolic adaptation. After the competition, the levels of IL-6 and apelin in particular increased – two of the body’s own signaling substances that are associated with energy supply, fat metabolism, blood circulation and recovery.
These changes indicate that seawater can help the body to switch to regenerative processes more quickly without stimulating it artificially.
Conclusion: Seawater does not have a performance-enhancing effect in the classic sense, but it can have a positive influence on biological recovery mechanisms after extreme endurance exercise.
Background
Triathlon competitions place high demands on the fluid and mineral balance. Long periods of exertion, heat and limited drinking options often lead to dehydration and electrolyte loss. These factors can impair cardiovascular stability, increase inflammatory reactions and delay regeneration.
In addition to traditional hydration strategies, the use of purified seawater is increasingly being discussed. In addition to sodium and chloride, seawater also contains magnesium, potassium, calcium and numerous trace elements that are involved in muscle metabolism, vascular function and cell protection. The aim of this study was to investigate whether seawater influences the release of myokines and cytokines, which are relevant for adaptation and recovery, during a triathlon.
Study design
The study was conducted as a randomized, double-blind crossover study with experienced male triathletes. Each participant completed several triathlon competitions under identical conditions, but with different hydration strategies:
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Treated seawater
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physiological saline solution (placebo)
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normal drinking water
During the competition, the drinks were consumed in small portions at fixed times. Blood samples before and after exercise were used to analyze inflammatory and myokine markers.
Central results
No increase in performance
The competition times, heart rate, lactate values and subjective stress did not differ significantly between the hydration forms. Seawater therefore had no ergogenic effect, i.e. no performance-enhancing effect.
Modulation of IL-6
After the triathlon, only the seawater group showed a significant increase in IL-6. While IL-6 is negatively evaluated in connection with chronic inflammation, it is considered a positive signaling substance during physical exertion, which increases energy availability, has an anti-inflammatory effect and initiates regeneration processes.
Increase in Apelin
The level of apelin, a messenger substance associated with vascular function, blood circulation, fat metabolism and mitochondrial activity, also only increased after seawater intake. Apelin is considered an important mediator between muscle work and metabolic adaptation.
No broad non-specific hormone response
Other myokines and hormones studied remained unchanged, suggesting that seawater specifically activates certain adaptive signaling pathways without overstimulating the endocrine system as a whole.
Physiological classification
The authors interpret the results to mean that seawater supports metabolic adaptation and regeneration after extreme endurance exercise. The combination of minerals and trace elements could promote the activation of the cellular energy regulator AMPK and thus promote oxidative metabolic processes.
Limitations of the study
The effects were only examined acutely. Whether regular or long-term intake of seawater leads to additional adaptations or improvements in performance remains to be seen. In addition, only male athletes were examined.
Conclusion
Seawater is not a classic performance enhancer, but it does have a targeted effect on myokines and inflammation-modulating signaling pathways that are crucial for regeneration, metabolic adaptation and exercise tolerance.
The study suggests that seawater may be a functional hydration strategy for extreme endurance exercise – particularly to aid post-competition recovery.