To prevent dehydration (fluid deficiency), attention must be paid to reducing individual risk factors. Behavioral risk factors
- Diet
- Inadequate fluid intake – To prevent dehydration, drink enough fluids evenly throughout the day:
- Daily drinking amount about 1.5-2 liters / day or 35 ml of water intake through drinks (= drinking amount) and solid food/kg bw / day.
- Suitable are: Mineral water, fruit and herbal teas, juice spritzers or broths.
- Inadequate and insufficient replacement of lost fluids due to sports, sauna, high ambient temperatures, diseases such as vomiting and diarrhea, fever.
- Inadequate fluid intake – To prevent dehydration, drink enough fluids evenly throughout the day:
Environmental pollution – intoxications (poisonings).
- Heat (heat day: > 30 °C; desert day: > 35 °C).
Preventive measures in the heat
- Nutrition
- Attention should be paid to an adequate amount of drinking (eg, high-sodium mineral water, isotonic sports drinks or fruit juice spritzers in a ratio of 3/4 to 2/ 3 water to 1/4 to 1/3 juice).
- As far as no diseases (eg heart failure / cardiac insufficiency) limit the fluid requirement – per kilogram of body weight 35 ml (from the age of 65: 30 ml) of water per day; in case of heavy sweating, the drinking amount increases to more than 3 liters / day; to note, only if the urine is light, the fluid intake is sufficient!
- In very hot weather, water with a sodium content of 400-800 mg / l should be drunk; if necessary, high-salt diet or taking salt tablets in heat-exposed persons; also a sufficient supply of magnesium and potassium is required – after several hours of continuous exercise about 300 mg potassium / liter are lost through sweat.
- Abstain from alcohol and drugs!
- Clothing
- When outdoors, headgear should always be worn.
- Lightweight, air-permeable clothing should be worn, rather than tight-fitting clothing.
- The clothing should be as light as possible, so as not to put additional stress on the body by stored heat…
- Sunglasses with optimal UV protection (UV400) should always be worn; these block all UV rays below 400 nm (UV-A, -B, -C).
- Physical activity
- Before heavy exertion, the body should be accustomed to the new climate (sufficient acclimatization).
- Heat acclimatization (heat acclimatization) occurs only through physical activity and lasts about 4 to 5 days.
- For training, use the cool morning hours or the evening hours.
- Limit physical activities when the temperature in the shade is high.
- Already from 28 ° C can lead to circulatory problems, sunstroke, heat stroke or dehydration (dehydration) during strenuous exercise (especially endurance sports).
- At a humidity of more than 80% or ozone values of more than 180 μg/m3 air is to refrain from an intensive running training.
- Recreational activities only to the extent that these, taking into account air temperature, humidity and air movement, do not lead to physical overload!
- In high temperatures, the last meal before a sporting activity should be at least two hours ago.
- For endurance sports, start with a maximum of 30 to 40 minutes at reduced intensity; heart rate should not be more than 10 beats higher than normal.
- Body care and cooling down
- Frequent cold showers without detergent or detergent (to prevent sebum depletion); if necessary, it may be sufficient to hold the arms up to the elbows in cold water or refresh the calves by treading water in a bucket of cool water.
- Medications: some medications can negatively affect thermoregulation or provoke desiccosis (dehydration):
- Anticholinergics, antidepressants: increase heat production and thus increase body temperature, which leads to increased sweating and thus also to electrolyte losses!
- Beta-blockers: reduction of cardiac output (cardiac output), which may affect heat adaptation.
- Diuretics and ACE inhibitors/angiotensin II receptor antagonists: dehydration (fluid deficiency) and/or electrolyte imbalance (imbalance of body salts) due to hyponatremia (sodium deficiency).
- Neuroleptics, Selective Serotonin Reuptake Inhibitors (SSRIs): inhibition of central thermoregulation.
- Muscarinic receptor antagonists: reduction of sweat secretion and thus risk of overheating.
- Sedation by dopaminergic and Parkinson’s drugs: lowering the perception of heat exhaustion or reducing the feeling of thirst and thus risk of dehydration.
- The State Health Office in Lower Saxony (NLGA) points to risks from other drugs. These include non-steroidal anti-inflammatory drugs (NSAIDs), antiarrhythmics, biguanides, H1 antihistamines, pseudoephedrine, sulfonamides and sulfonylureas.
- Notice:
Travel advice: when traveling in countries with hot or hot and humid climate, a consultation regarding the intake of medication is required!
