Fatigue is mainly categorized into exercise fatigue and chronic fatigue. Among them, exercise fatigue is a phenomenon of temporary decline in body functions caused by exercise, which can be relieved by supplementing amino acids, traditional Chinese medicine or vitamin functional foods; chronic fatigue will not be relieved by supplementing body functions and resting, which is accompanied by symptoms such as sore throat, headache, muscle and joint pains, inability to concentrate and memory loss, etc., with repeated episodes of prolonged duration and a high incidence of morbidity. The cause of its onset is unclear, but it is bound to be related to exercise fatigue.

The pace of modern life is getting faster and faster, and people’s fatigue has been increasing continuously in recent years, with a larger base of people suffering from locomotor fatigue, and the incidence of chronic fatigue syndrome is also gradually increasing. Therefore, timely relief of exercise fatigue and attention to dietary health care are important for the prevention of chronic fatigue syndrome. This article reports on the analysis of functional foods for the relief of exercise fatigue, with the aim of analyzing the characteristics and benefits of functional foods to improve people’s quality of life.

Overview of fatigue

The definition of fatigue, i.e., the inability of an organism to maintain or achieve a pre-determined exercise intensity due to insufficient or interrupted supply of physiological functions, was proposed by exercise biochemistry scholars at the International Conference on Exercise Biochemistry in 1982 (5th session).

Up to now, the mechanism of exercise fatigue is very different, and there is no very specific and precise theory to confirm the cause of exercise fatigue. At present, there are nine major theories, namely, free radicals, mutation theory, protective inhibition, ion metabolism disorders, immune dysfunction, endocrine mediation disorders, metabolite accumulation and energy depletion. Fatigue is actually a kind of protective reaction of the body, which only occurs when the body functions are overly exhausted and life-threatening, thus reminding the athletes or workers to reduce the intensity of exercise and work intensity to prevent damage to the body.

Analysis of Anti-fatigue Functional Foods

2.1 Vitamins

Enzymatic and non-enzymatic systems in the body can scavenge free radicals. In the enzyme system, GPX (glutathione hydrolase) can remove lipid peroxides, SOD (superoxide dismutase) can remove peroxyl radicals and superoxide radicals, and CAT (catalase) can remove hydrogen peroxide; and the non-enzymatic system includes coenzyme Q, reduced glutathione, β-carotene, vitamin C, and vitamin E. The enzyme system can remove free radicals in the cells of organs of the body.

A variety of antioxidants in the cells of the organism’s organs are maintained at a relatively balanced level, which produces a variety of oxidative stress on the organism, and removes macromolecules such as free radicals, proteins, nuclear enzymes and protective lipids in time to protect the organism from the attack of free radicals, which is an important mechanism in the human body. Therefore, supplementing the body with vitamins can effectively relieve fatigue.

Vitamins with anti-fatigue function and more common main vitamin E, vitamin C, vitamin A and vitamin B group.

Among them, vitamin E is an antioxidant, which can act on cell membranes and subcellular structural membranes to prevent free radicals from oxidizing unsaturated fatty acids in biological membranes;

Vitamin C can not only provide the body with hydrogen atoms, but also help the body to scavenge free radicals and convert oxidized glutathione into reduced glutathione, which has the effect of reduced ascorbic acid;

Vitamin A can improve the antioxidant status of the body and also inhibit the generation of oxygen free radicals during exercise, reduce the oxidative stress damage of the body, delay the body’s fatigue, thus enhancing the body’s exercise capacity;

Vitamin B1 and vitamin B2 in the vitamin B family have anti-fatigue effects, and the body will have a large amount of lactic acid and pyruvic acid accumulation after the lack of vitamin B1, and vitamin B2 in the body can participate in the redox reaction and energy generation as a coenzyme in the trihydroxy acid cycle.

2.2 Amino acids
Amino acid deficiency will lead to a lack of raw materials for the synthesis of antioxidants and antioxidant enzymes, which will increase the number of free radicals, and ultimately in the metabolic process will be transferred to the material carrier for a large number of depletion of metabolic disorders or fatigue caused by the body.

For example, fat oxidation is the mitochondrial oxidation of carnitine, a fatty acid carrier. Carnitine is mainly generated during the metabolism of methionine and lysine, which promotes the oxidation of amino acids in the two keto acid branched chain, and removes excess fatty acyl CoA.

Urination during fatigue will excrete a large amount of botulinum toxin and severely weaken the body’s ability to oxidize and utilize fatty acids, thus leading to body fatigue. Therefore, supplementing the body with amino acids can effectively eliminate fatigue.

2.3 Trace elements
Magnesium, one of the trace elements, is commonly found in a variety of foods, such as fish, meat, fruits (most of them), green vegetables and peas, all of which contain large amounts of magnesium.

If people are biased and picky eaters, do not like fish and meat, prefer a certain type of fruit and meat, or rarely eat fruit and green vegetables, they will suffer from magnesium deficiency, leading to fatigue. Therefore, supplementation of magnesium is of great importance to people who are partial to food.

2.4 Protein
Protein is an indispensable part of functional food and an important source of nutrition for the human body. Once protein deficiency occurs, it will have an effect on the physiological regulation of the body and trigger fatigue.

Protein-containing foods are relatively abundant, such as animal proteins such as fish, shrimp, eggs, milk, poultry and animal meat, legume plant proteins such as soybeans, soybeans, large green beans and black beans, and dried fruit plant proteins such as pine nuts, sesame seeds, walnuts, melon seeds and almonds.

2.5 Traditional Chinese Medicine
There are more anti-fatigue herbs in the Chinese medicine category, and the common ones are Epimedium, pollen, ginkgo biloba, aloe vera, gynostemma and rhodiola rosea, etc. Among them, Epimedium contains a large amount of anti-fatigue herbs.

Among them, Epimedium contains a large number of MDA that can increase the SOD activity of erythrocytes; pollen contains amino acids, proteins, trace elements and vitamins, etc., and the nutrients are very comprehensive; Ginkgo biloba contains diterpene lactones and flavonoid glycosides, which have the effect of scavenging free radicals, strengthening the ability of resistance to hypoxia, as well as improving the metabolism of the heart and the brain; Aloe vera contains flavonoids antioxidant substances, a variety of amino acids, vitamins, and has strong antioxidant capacity; Gynostemma has a wide range of pharmacological effects, and its total saponins can improve free radical metabolism and delay the onset of fatigue; Rhodiola rosea contains myo-glycogen, which improves the body’s ability to withstand hypoxia.

Conclusion

Chinese therapeutic food and health care culture is very rich, with a very long history, the combination of functional food and therapeutic food and health care has unique advantages in the development of functional food. Fatigue is mainly caused by insufficient energy supply of the organism, and it is of great significance to conduct in-depth research on functional foods, such as vitamins, amino acids, and traditional Chinese medicines, which are effective in antioxidant, anti-stress, and anti-fatigue effects.