Nutritional principles the day before the exam
The main preparation rule is not to abruptly change your usual diet on the eve of the Unified State Exam (USE). The body is adapted to a certain set of foods, and experiments during a stressful period can cause digestive problems, drowsiness, or discomfort that will affect concentration.
However, if there is time to spare (for example, between biology and chemistry exams), it is permissible to gently adjust your diet:
- reduce heavy animal proteins (fatty meat, fried chicken) — the body spends a significant amount of energy digesting them;
- try a day without dairy products and assess how you feel;
- eliminate simple carbohydrates — chocolate bars, sweet pastries, white pasta, which cause a sharp surge in insulin and a subsequent energy crash.
If your usual breakfast is tea or coffee, you should keep it. Suddenly giving up caffeine in a person accustomed to it provokes a headache and decreased performance.
Why energy drinks don't work
Energy drinks create the illusion of increased productivity, but in reality, they reduce the quality of concentration. Their effect is based on a combination of caffeine, taurine, and B vitamins, which are absorbed quickly and metabolized just as quickly.
Physiological scenario after consuming an energy drink:
- a sharp rise in glucose levels and activation of the sympathetic nervous system;
- the onset of anxiety, tachycardia, tremors;
- rapid breakdown of active substances;
- an energy "crash" — a state below the baseline level of alertness.
The anxiety accompanying the caffeine rush scatters attention, which is critical when working on part 2 tasks in chemistry (26, 32, 33) or genetics problems in biology, where sustained concentration is required.
Chocolate and sweets: the myth of "brain fuel"
The widespread belief that a bar of chocolate during an exam provides a steady influx of energy to the brain does not hold up to scrutiny. Glucose is indeed the main substrate for neurons, but when a large amount of simple sugars enters the body, the same mechanism of an insulin spike and subsequent drop in blood sugar is triggered.
Theoretically, it is possible to use dosed intake of small portions of sweets when signs of fatigue appear, but this requires precise knowledge of your own body's reactions. In practice, under exam conditions, such control is almost unattainable: a cyclic dependence on glucose reinforcement is formed, and each subsequent intake has to be increased.
Water and sleep schedule
The only universal recommendation is adequate hydration. The day before the exam, it is useful to drink 2–3 liters of pure water. Adequate water balance:
- improves sleep quality and the speed of falling asleep;
- supports the functioning of the central nervous system;
- ensures normal blood rheology and oxygen delivery to the brain;
- reduces fatigue levels throughout the day.
Sleep should take place in a well-ventilated room: oxygen concentration directly affects recovery and cognitive functions the next day.
Stimulants and nootropics: why this is not an option
No pharmacological stimulants increase attention span in the long term. This applies both to historically known amphetamine-like drugs and modern agents positioned as nootropics (phenotropil, racetams, and analogues).
Their effect boils down to a short-term surge in activity accompanied by anxiety and impaired goal-directed thinking. Similarly, taking sedatives before an exam is undesirable: sedative medications slow down reactions and impair the retrieval of information from memory. The best strategy is a stable routine, familiar nutrition, water, and restful sleep.
Key points
- On the eve of the USE, maintain your usual diet and do not introduce new foods.
- Simple carbohydrates cause an insulin spike and energy crash — avoid chocolate and sweet pastries.
- Energy drinks provide a short-term boost followed by a crash and anxiety.
- Heavy meat and fatty foods consume energy for digestion.
- The daily water norm is about 2–3 liters; hydration improves sleep and brain function.
- Sleeping in a well-ventilated room is more important than any "stimulants".
- Nootropics and pharmacological stimulants do not increase real concentration.
- Routine stability is more effective than any one-off "biohacks".