During endurance exercise, especially in the heat, the body loses a lot of fluid and minerals. This loss can lead to a faster accumulation of lactic acid (lactate) in the blood, which is one of the main signs of physical fatigue and limits performance.
This study investigated whether the intake of microfiltered, sterilized seawater before running has a positive effect on fatigue and metabolism. Experienced runners drank either a small amount of seawater or normal water shortly before a long running session.
The results clearly showed that the lactate levels in the blood were significantly lower in the runners with seawater after exercise. This indicates that the body was able to work more efficiently under stress and was less likely to enter a fatigued metabolic state.
The researchers attribute this effect to the natural combination of minerals and trace elements in seawater. These substances are lost during sweating and are important for muscle work, nerve function and the energy balance.
Conclusion: A small amount of purified seawater before training can help to reduce fatigue and improve endurance during endurance exercise – especially in the heat.
Background
Endurance training in warm environments places a particular strain on the body. Sweating leads to fluid and electrolyte loss, which affects blood volume, temperature regulation and energy metabolism. A known consequence is earlier and stronger lactate formation, which is associated with muscular fatigue, a drop in performance and subjective exhaustion.
In addition to conventional rehydration strategies, the role of mineral-rich solutions is increasingly coming into focus. In addition to sodium, potassium, calcium and magnesium, seawater also contains numerous trace elements that are relevant for enzymatic processes, muscle contraction and the acid-base balance.
Study design
The study was conducted as a randomized, double-blind crossover study. Experienced male runners completed two identical running units at a high ambient temperature.
Shortly before the run, they either drank:
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microfiltered, sterilized seawater or
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the same amount of normal water.
During the run, fluid loss was deliberately induced to simulate realistic competition conditions in the heat. Blood lactate levels were measured at regular intervals to assess metabolic stress.
Central results
Reduced lactate formation
After exercise, the lactate concentration was significantly lower with seawater intake than after normal water. This indicates a more efficient energy supply and less acidification of the muscles.
Better metabolic stability
The lower lactate formation indicates that seawater supports the body in delaying the transition to highly fatiguing metabolic processes. This is particularly relevant during prolonged exercise in the heat.
No overload due to drinking quantity
Since only a small amount of fluid was consumed before the run, there was no stomach strain or performance disadvantages due to excessive drinking. The effect therefore does not appear to be due to the amount of fluid, but to the mineral and trace element composition.
Possible mechanisms of action
The authors discuss several possible explanations:
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Compensation of electrolytes lost through sweating
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Stabilization of the acid-base balance
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Support for muscle and nerve function
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Indirect shift of the lactate threshold to higher loads
Together, the minerals could help to keep the metabolism in the aerobic range for longer and thus delay fatigue.
Classification and limits
The study shows acute effects with a single intake under clearly defined conditions. The authors point out that the composition and origin of seawater are decisive and that the results cannot automatically be transferred to every product.
Long-term effects, optimal dosages and possible differences between training and competition situations need to be investigated in further studies.
Conclusion
Taking microfiltered seawater before endurance exercise can lower lactate formation and reduce metabolic fatigue, especially when training in the heat. The effect is presumably based on the synergistic combination of natural minerals and trace elements.
The study supports the approach that targeted mineral supplementation can be a useful addition to classic hydration strategies for endurance athletes.