Exercise consumes a lot of energy, and the blood sugar concentration will be lower. Blood sugar is the direct energy substance of the brain. When the blood sugar concentration is low, the brain will feel tired because of lack of motivation, people will feel dizzy and weak, and some people will look pale and break out in a cold sweat. If it continues, it will be unconscious, even unconscious.

It is more appropriate to eat fruits and vegetables half an hour before exercise, and strenuous exercise should be 1-2 hours ago.

Being particularly tired is harmful to your health. Healthy exercise should be that you are a little tired after exercise, but not very tired, and you are full of energy the next day, which can exercise without affecting your daily life.

The general principles of sports water supplement are "preventive supplement" and "small amount and multiple times". When exercising, you should follow the principle of preventive hydration and a small number of times.

2 hours before exercise, add 250-500ml of water, 15-20mm before exercise. Then replenish 120-240ml of water every 15-20min. Do not exceed 800 ml per hour.

The water replenishment interval can be shortened in summer. The water temperature is between 8- 16 degrees Celsius. During exercise, if the time exceeds 1 hour, drink some light salt, add 0.11-0.15g salt to each liter of water, and control the water temperature at 15-22 degrees Celsius.

Drinking sports drinks containing appropriate amount of sugar after exercise can help the electrolyte to be fully absorbed by cells and quickly recover physical strength in the shortest time.

After exercise, a small amount of water should be replenished many times, and sugar should be supplemented immediately after exercise. 2 hours after exercise is the best time to resume exercise and consume sugar. Don't wait until you get home to eat. Or you can add some sugar to the boiling water at the ratio of 1: 15. "Adding sugar to water is to maintain a certain blood sugar concentration, delay the occurrence of fatigue, and thus ensure the health of bodybuilders.

1. Don't hydrate when you are thirsty. People often take thirst as a sign of hydration, which is wrong. When people feel thirsty, the degree of dehydration has reached 3% ~ 4% of their body weight, and then their physical fitness has declined. And when you feel thirsty, you will always be in a state of "water debt" during exercise, and the fitness effect can not be guaranteed.

2. Don't add white water and tea. Supplementing white water or tea during exercise will dilute the blood, and the added water will soon be lost from the skin, which can not meet the needs of the heart.

3. Don't supplement juice and juice drinks. The concentration of fruit juice and fruit juice beverage is relatively high, and the osmotic pressure is also high. High osmotic pressure prolongs the time for water to pass through the stomach, slows down the absorption speed in the intestine, and dehydration during exercise cannot be recovered as soon as possible.

4. Don't supplement carbonated drinks. Some fitness enthusiasts like to drink cola and other drinks, which contain carbonic acid gas, which will cause flatulence in the stomach and make the body feel uncomfortable during exercise, thus affecting the fitness effect.