Why plain water sometimes isn't enough, and why most electrolyte products are sugar water with marketing.
Sodium. Most people cutting calories also cut processed food, which is where most of their sodium came from — and then wonder why they feel dizzy standing up, get headaches, and have flat workouts. Sweating in training compounds it. Drinking more plain water can make it worse by diluting what's left.
The eight-glasses rule has no strong evidence behind it. Thirst plus urine colour is a reasonable guide for most people. Training, heat, high protein intake and caffeine all raise requirements. If your urine is consistently dark or you're getting headaches in the afternoon, drink more; if you're up three times a night, drink less in the evening.
Sodium is the one people actually run short of when they clean up their diet. Potassium comes from fruit and vegetables and most people are low regardless. Magnesium is commonly under-consumed and worth attention if sleep and cramping are problems. Chloride tags along with sodium. Everything else in a fancy electrolyte blend is present in trace amounts for the label.
Most sports drinks are sugar with a little sodium. Most electrolyte powders are sodium and potassium with flavouring — which is fine, but you're often paying a premium for salt. A pinch of quality salt in water plus fruit for potassium does the same job for pennies. Products are convenient, not superior.
Sessions over an hour, hot conditions, heavy sweaters, low-carb diets (which flush sodium), and anyone in a deficit eating mostly whole foods. In those cases sodium before and during training makes a noticeable difference to how strong you feel.
Applying this around a real schedule is where most plans break. Coaching exists for exactly that gap.
Salt your food deliberately rather than avoiding it, unless a physician has told you otherwise. Add a pinch to your training water. Eat fruit and vegetables for potassium. Consider magnesium in the evening if sleep or cramping is an issue. Skip anything promising cellular hydration technology.
Usually not for under an hour in a temperate gym. Water and a normal diet cover it.
Guidance varies by individual and existing blood pressure. This is a physician conversation, not a blog one.
Cramping is multifactorial — fatigue, sodium, magnesium, and training load all contribute. Sodium is the easiest to test.
Your schedule, your appetite, your training history, your injuries — applied instead of explained.
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