2.1 The Complete Book of Fitness Nutrition

1. Water

The higher the environmental humidity, the harder it is for sweat to evaporate, so more water needs to be replenished. Water is also part of muscle cells. When muscle glycogen is depleted, water is released, so the muscles look flatter. An increase in water causes cells to enlarge and is an initial signal for protein synthesis. There are several types of diarrhea; osmotic diarrhea is nothing to worry about. Drink enough water every day, about 1.5 L, and keep urine from becoming too yellow (so the kidneys have less workload). The breakdown of carbohydrates, fats, and proteins produces metabolic water. Starch and sugar leave the stomach the fastest, taking a little over one hour; fat is the slowest, taking more than six hours; protein is in between, taking a little over three hours. Endurance trainees exercising for less than 90 minutes only need mineral water. They do not need isotonic drinks or electrolyte supplementation (that is, minerals). Strength trainees should drink mineral water rich in sodium (400–1100 mg/L) during training, and replenish mineral water rich in sodium, calcium, and magnesium after training. Caffeine can increase arousal and thereby improve exercise performance. Alcohol is unfavorable for both fat loss and muscle gain.

2. Carbohydrates

Carbohydrates are sugars. Sugars include glucose, fructose, galactose, sucrose, lactose, maltose, and starch. For a normal healthy person, digestive and absorption efficiency is roughly similar; there is no situation where someone simply cannot gain or lose weight. Fruit is not especially high in fructose; honey and sucrose are much higher. Eating too much fructose is not very healthy because it is metabolized through the liver and hardly triggers insulin secretion. Galactose also needs to pass through the liver and hardly triggers insulin secretion. After oral glucose intake, blood glucose rises rapidly. Maltose triggers a large amount of insulin secretion. After prolonged aerobic exercise, it is not recommended to eat foods that may cause allergies, because they can irritate the gastrointestinal tract. Dietary fiber helps with weight loss and provides strong satiety. Eat at least 130 g of carbohydrates per day. If carbohydrate intake remains low for a long time, gluconeogenesis (protein, lactate, glycerol -> glucose) occurs. In most cases the source is protein, so muscle is lost. If there is no sugar, protein is used for energy before fat. How sugar is used: oxidation for energy -> glycogen -> conversion into fat. The ability to convert carbohydrates into fat is weak. Excess sugar is stored by the liver as muscle glycogen and then slowly released during sleep. Strength training requires sufficient carbohydrate intake. In the short term, consuming a large amount of carbohydrates will not cause a major increase in body fat, but over the long term it will. Most body fat still comes from dietary fat, so a low-fat diet is needed. Muscle glycogen stored in a particular muscle is used by that muscle and cannot be converted into blood glucose. Soreness the next day is not caused by lactic acid. A low-fat, high-carbohydrate diet is quite good. Understand GI and GL. Eating high-GI foods after training is very beneficial for muscle gain. Supplement protein at the same time (1 scoop of protein powder + 40–50 g of glucose). Creatine is also very good. The key is promoting insulin secretion. Insulin helps muscle gain but is unfavorable for fat loss. Regular strength training combined with endurance training is beneficial for insulin secretion.

Muscle fibers are torn during training and then recover and grow during rest; carbohydrates and protein are needed for that recovery and growth. Per kilogram of body weight, consume 1.8 g of protein and 6 g of carbohydrates. Moderate-intensity endurance training for 45 minutes, five days per week, is good for fat burning. High-intensity exercise only needs to be done three days per week. Combining the two is best. Do not exercise on an empty stomach. Consuming high-GI carbohydrates and protein before exercise and at breakfast noticeably helps muscle gain. Immediately after exercise, high-GI foods can be eaten for rapid recovery. Consuming carbohydrates immediately before and after exercise, and eating within one hour after exercise, can reduce muscle-protein breakdown. Long-term low-GI, high-carbohydrate, low-fat eating can control body-fat percentage while increasing body weight. After exercise, take small sips of water containing salt.

For fat burning, long-duration low-intensity endurance exercise is effective, moderate intensity is best, and high intensity mainly uses muscle glycogen. Exercise for 45 minutes three times per week for fat burning, or do high-intensity strength training three times per week. Low-intensity endurance training has little significance for fat loss. For anaerobic exercise, exhale during exertion and inhale during the return phase. After exercise, muscle cells sustain micro-damage and insulin sensitivity decreases at this time, but this does not need much attention because strength training improves insulin sensitivity. The calories from sugar substitutes do not need to be considered, but their sweetness may stimulate appetite.

3. Fat

A healthy body-fat percentage for men is around 15%. Fat can be divided into short-chain fatty acids (enter the blood directly), medium-chain fatty acids (enter the blood directly), and long-chain fatty acids (saturated [animal-based staple foods, solid] + unsaturated [monounsaturated (good) + polyunsaturated (omega-3 is good)] + trans fatty acids [hydrogenated vegetable oils are bad!!]). High-carbohydrate, low-fat diet: compared with other diets, it is better for both muscle gain and fat loss. L-carnitine is useless. Ideal fat burning: exercise duration, exercise intensity, and exercise frequency. Moderate-intensity endurance training for 60 minutes, five times per week. High-intensity exercise only needs three to four days per week. Maintaining body fat: combine endurance training with strength training. Morning fasted exercise helps increase the fat-burning rate, but whether it actually reduces fat is unclear. Eating high-carbohydrate food before morning exercise affects fat burning, while low-carbohydrate + high-protein intake has almost no effect. Eating high-GI + high-protein food after fasted exercise helps muscle gain. Consuming carbohydrates during exercise affects the fat-burning rate. To actually reduce fat, calorie intake still needs to remain lower than calorie expenditure over a period of time.

4. Protein

Grains + seeds Grains + dairy products Grains + legumes

There is no need to supplement a large amount of protein, though enough protein still needs to be consumed. The higher the biological value of a protein, the better; it can reduce the breakdown of protein in muscle. Consuming protein before and after exercise can reduce muscle-protein breakdown. For strength trainees, protein requirements only increase when hard endurance training is combined with regular strength training, so under normal circumstances there is no need for additional protein supplementation. For strength trainees who want the best muscle-gain results, sufficient protein and energy are required (1.4–1.8 g per kg of body weight). Athletes can get the best muscle-gain results by consuming 0.5 g of protein per kg of body weight at each meal and leaving enough time between meals. Eating the first meal as soon as possible after exercise can produce the best muscle-gain results. If a large amount of protein intake has an unfavorable effect on testosterone, consuming fat can address this problem. A high-protein diet can create satiety and increase heat production, helping body fat remain stable. Current research has not found health effects from very high protein intake (for example, 2.8 g per kg of body weight).

5. Energy Balance

1 Calorie = 1 kilocalorie = 1000 calories = 4186 joules = 4.186 kilojoules.

Creatine is effective for muscle gain. Ideal approach: consume 10 g of creatine one hour before training; consume whey protein + glucose half an hour before training; immediately after training consume 10 g of creatine; half an hour later consume whey protein + glucose; then, after a relatively short interval, eat a large meal containing carbohydrates + protein. Energy requirement = thermic effect (10%) + activity metabolism (30% daily activity + physical activity) + basal metabolism (60%). To gain muscle, the body must have a calorie surplus, namely basal metabolism + 500 kcal. Energy estimate: basal metabolism = lean body mass * 22 + 500 = 48.1 * 22 + 500 = 1559 kcal. Then multiply by a coefficient: on training days, 1.8 * 1559 = 2806; on non-training days, 1.5 * 1559 = 2338. Half a scoop of protein powder + milk: 192 + 350 1.5 bowls of rice + fatty beef + vegetables + two eggs: 250 * 1.5 + 76 * 2 + 150 Baozi + milk: 223 + 192 One scoop of protein powder + 10 g glucose; 1.5 bowls of rice + pork: 500 + 150 + 250 * 1.5 + 27 * 4

2501.5+762+150+192+350+223+192+500+150+2501.5+274

Long-term fat loss = increase satiety + reduce appetite. Appetite: whether appetite increases or decreases after exercise depends on the person. Energy density of food: foods with greater volume and higher water content are better for fat loss.

49.9 87.6 71 82.9 25

6. Micronutrients

Vitamins Major minerals + trace minerals: dairy products + fish

7. Diets

Choose from a wide variety of foods. Maximize fat loss while minimizing muscle loss. Maintain it over the long term.

7.1. Low-Fat Diet

Can reduce fat quickly. Low-fat diet + lots of exercise. Eat plenty of fruit and vegetables. Eat smaller meals more frequently.

7.2. Mediterranean Diet

Can be used for both muscle gain and fat loss, and is flexible to follow.

Diabetes Diet Management: Glycemic Index and Glycemic Load