膳食脂肪对战士耐寒力与脂代谢的影响

EFFECT OF DIETARY FAT ON THE COLD-RESISTANCE AND THE LIPID METABOLISM OF RECRUITS

目的：为进一步验证增加膳食脂肪供应量提高机体耐寒力的效果。方法：选寒区部队刚入伍新兵５４ 人。设普食对照组２５ 人，脂肪生热比为２５ ％ 左右；高脂膳实验组２９ 人，脂肪生热比为３０ ％ 左右。用标准称重法膳食调查计算脂肪生热比。在相同气侯条件、相同训练强度分别食两种膳食２３ ｄ 。测定实验前、后新兵耐寒力水平和脂代谢状况。结果：①实验前血管寒冷反应指数（ＶＲＣＩ）７３ ．５ ％为弱反应；着冬装在－ ７ ～－ ９ ℃冷环境静坐４ ｈ，肛温下降０ ．７９ ～０ ．９５ ℃，两组无显著性差异。②实验２３ ｄ 后，ＶＲＣＩ两组均未提高，反而下降，但实验组下降程度明显小于对照组，实验组４ ｈ 冷暴露肛温下降０ ．６３ ±０．１６ ℃，显著小于其对照组０ ．８３ ±０ ．２０ ℃（ Ｐ＜ ０ ．０１） 。③甘油三酯，总胆固醇均在正常值范围。结论：本次结果和１９９３ 年部队验证均表明提高膳食脂肪生热比到３０ ％ ～３５ ％ ，短期食用可明显提高战士耐寒力，脂肪生热比３０ ％ 为军队营养标准的上限是可行的。

Objective: It is to confirm the results that high fat diet could enhance the cold-resistance. Methods: 54 recruits of cold zone were divided into two groups at random, 25 of them, as a control group, taking the diet in which fat provided 25 percent of all energy, 29 of them as an experimental group, taking the high fat diet in which fat provided 30 percent of all energy. The experimental period 23 days, during the time they lived under the same climate condition and were trained at the same level. The cold-resistance indices VRCI and rectal temperature were tested before and after the experiment. Results:①Before experiment, 73.5% was weak reaction of VRCI and the rectal temperature decreased 0.79～0.95 ℃ after 4 hours cold exposure. There was no difference between two groups. ②Affer 23 days of experiment, there was still no difference of VRCI between two groups , but the decrease range of the experimental group (0.63±0.16 ℃) was smaller than that of control(0.83±0.20 ℃). ③ In both of the experimental and the control groups, levels of total cholesterol and triglyceride in plasma were in the normal range.Conclusion: Taking high fat diet (fat providing 30% of energy) for 23 days could enhance the recruit's ability of cold resistance, but there was no effect on lipid metabolism. Based on our results, we think that it is feasible to take the high fat diet (30%～35% of energy) as the upper limit of RDA in cold zone. For evaluating the ability of cold-resistance, two indices of rectal temperature and VRCI were more sensitive then one index of VRCI alone.