Safer Cars
Safer Cars
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更安全的汽车
DOI：
10.1136/bmj.2.5413.834
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发表时间：
1964
影响因子：
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通讯作者：
Helen E Heslop
中科院分区：
文献类型：
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作者：
Helen E Heslop
由W. Kohlrausch在1928年4，他的结果和坦纳的同意，但1928年的运动员相当小。坦纳发现运动员之间存在着相当大的差异，这并不奇怪，但值得注意的是，运动员在任何一个项目中都是如此相似。他书中的照片显示了一名日本人和一名澳大利亚人在三级跳远中表现出色;他们几乎一模一样。这将是任何人都很难通过坦纳的书中的插图挑选出运动型，因为有这么多的类型。最后一个原因是大多数教练都支持的，那就是更好、更有效的训练方法。这是最难进行回顾性调查的，而且几乎没有客观证据。当然，今天的顶级运动员花在训练和练习上的时间比25年前还要多。培训现在持续了一年中的大部分时间，如果不是全部的话。这说明了一个关于业余身份的问题。任何想成为奥运会运动员的人都很难在为之训练的同时靠体育以外的职业谋生。坦纳的结论是：“成绩的提高不仅是因为更好的训练和更好的比赛，而且因为我们有更好的系统来寻找最适合成为运动员的人。“在奥运会上创造世界纪录的人不多，有很多可能的原因，包括心理压力、不熟悉的环境和物理环境。然而，尽管上届奥运会是在炎热潮湿的天气下在罗马举行的，但大多数项目都创造了奥运会纪录，还有几项世界纪录。东京的气候可能与罗马相当相似，但1968年的奥运会将在海拔约7,500英尺的墨西哥举行。（2，300米）。径赛项目，特别是长距离项目的成绩似乎极有可能受到不利影响。短跑运动员可能没问题，因为100米赛跑主要靠无氧代谢进行。跳高和投掷运动员甚至可能受益，因为氧气分压的降低对肌肉的爆发力没有太大影响，而空气密度的降低会略微提高成绩。毫无疑问，教练和运动员会要求提供意见，而这并不容易满足。对于那些生活在海平面的人，有什么训练方案或程序可以建议？这是一个不寻常的研究问题，因为目前生理学家发现很难发现低至7，500英尺的海拔高度有任何明确的影响。然而，来自英格兰的足球队在墨西哥城的表现一般都很差，足以表明有一些生理恶化。但这远不是运动员的唯一研究问题。今天，许多国家建立的研究机构主要是为了研究运动员。然而，令人惊讶的是，在英国，特别是考虑到A。希尔，J. Barcroft等人，以及我们的运动成就的历史。许多生理和临床问题值得关注。显然，重要的是要知道在特定事件中至高无上的人的特征;然后我们可以了解人体能做什么。人类最大的心输出量，最大的耗氧量，最大的肌肉力量是多少？训练中发生的变化更令人感兴趣。令人惊讶的是，我们仍然没有正确理解训练是如何提高成绩的。我们甚至不确定肌肉本身发生的变化。A. Krogh在他的经典作品中表明，当肌肉经过训练时，毛细血管的数量会增加，并且在各种动物的研究中也有类似的发现。这种变化尚未在人类身上发现，其机制也不清楚，尽管缺氧被认为是其原因。当肌肉由于训练而增加力量时，纤维的大小或数量是否增加？证据表明是前者，但不是决定性的。肌肉收缩的神经控制可能发生的变化现在才受到怀疑。[6]对于肌肉损伤、肌肉萎缩和运动神经损伤的合理治疗，需要大量的这方面和其他方面的信息。问题列表可以扩展到几页，但只会给出两个。什么是身体健康，如何衡量？肌肉锻炼对健康是必要的吗？如果是，需要多少？为什么？很多人可能会觉得最后一个问题的前半部分是不必要的，而且已经很清楚了，但要找到足够的证据并不容易。[2]有一个很好的理由相信，在相当长的一段时间里，肌肉的锻炼可以降低患冠状动脉疾病的可能性，但这一点没有得到证实。人们不再相信运动员通常患有“紧张”的心脏，并且有负面信息表明运动员和非运动员一样长寿。尽管英国运动员对这一问题普遍感兴趣，但他们看到国外为他们的同事做了什么，想知道为什么他们在这里相对被忽视。中央体育娱乐理事会、英国体育与医学协会、人体工程学研究学会的健身与训练分会都在以各种方式尽最大努力鼓励研究。但运动成绩是一个既困难又费时的课题，目前还没有足够的研究人员愿意从事这方面的研究。
carried out by W. Kohlrausch4 in 1928, and his results and Tanner's agree in general, but the 1928 athletes were considerably smaller. It is not surprising that Tanner finds considerable differences between athletes, but it is remarkable how similar are the athletes in any one event. Photographs in his book show a Japanese and an Australian who were distinguished in the triple jump ; they are almost identical. It would be difficult for anyone looking through the illustrations in Tanner's book to pick out the athletic type, for there are so many types. The final reason for the continual improvement in performance is the one that most coaches would support-namely, better and more efficient training methods. This is the hardest to investigate retrospectively and there is little objective evidence available. It is certainly true that top athletes to-day spend more time training and practising than was customary even 25 years ago. And training now continues for most, if not all, of the year. This illustrates one of the problems concerning amateur status. Anyone wanting to become an Olympic athlete will have great difficulty in training for it and at the same time earning a living in an occupation other than athletics. Tanner's conclusion is that, " Performances have improved not only because of better training and better competition, but because we have better systems for finding the most suitable men to become athletes." Not many world records are established at the Olympic Games, and there are a number of possible reasons, including the psychological strain, the unfamiliar setting, and the physical environment. Yet though the last Games were held in Rome in hot and humid weather Olympic records were set up in the majority of events and there were several world records. In Tokyo the climate may be rather similar to Rome, but the Olympics in 1968 will be held in Mexico at an altitude of about 7,500 ft. (2,300 m.). It seems highly probable that performance in track events, particularly long-distance events, will be adversely affected. Sprinters may be all right because the 100-metres race is run mainly on anaerobic metabolism. Jumpers and throwers may even benefit, since the reduction in the partial pressure of oxygen should not have much effect on the explosive muscular effort, and the reduced density of the air should slightly improve performance. No doubt there will be requests for advice from coaches and athletes which will not be too easy to meet. What training regimen or procedure can be suggested for those who live at sea-level ? Here is an unusual problem for research, since at present the physiologist finds it difficult to discover any unequivocal effects of altitudes as low as 7,500 ft. However, the performance of football teams from England in Mexico City has in general been poor enough to suggest that there is some physiological deterioration. But this is far from being the only research problem of the athlete. In many countries to-day research institutes have been established primarily to study athletes. Yet surprisingly little is done in Britain, especially in view of the outstanding contributions made in the past by A. V. Hill, J. Barcroft, and others, as well as our history of athletic achievement. Many questions, physiological and clinical, deserve attention. It is obviously important to know the characteristics of the man who is supreme in a particular event; then we can learn what the human body can do. What is the largest cardiac output, the highest oxygen consumption, the greatest muscle power of which man is capable ? And the changes that take place in training are of greater interest. It is surprising that wve still do not properly understand how training improves performance. We are uncertain even of the changes occurring in muscle itself. A. Krogh' in his classic work showed that the capillaries increased in number in a muscle when it was trained, and similar findings have been reported from studies on various animals. Such changes have not yet been found in man, and the mechanism responsible is obscure, though lack of oxygen has been suggested as the cause of them. When a muscle increases in strength as a result of training, do the fibres increase in size or in number ? The evidence suggests the former but is not conclusive. And the possible modifications in the nervous control of muscular contraction are only now suspected.6 Much of this and other information is needed for the rational treatment of muscle injuries, muscle atrophy, and damage to motor nerves. The list of problems could be expanded to fill several pages, but only two more will be given. What is meant by physical fitness and how can it be measured ? Is muscular exercise necessary for health; if so, how much and why ? Many may feel the first part of the last question is unnecessary and is already clearly established, but it is not easy to find adequate evidence. *There is a good case for believing that muscular work over a considerable period of life lowers the likelihood of coronaryartery disease, but it is not proved. It is no longer believed -that athletes commonly suffer from " strained " hearts, and there is the negative information that athletes live as long as non-athletes. Despite widespread interest in this subject British athletes, seeing what is done for their colleagues abroad, wonder why they are relatively neglected here. The Central Council of Physical Recreation, the British Association of Sport and Medicine, the Fitness and Training Section of the Ergonomics Research Society are all, in their several ways, doing their *utmost to encourage research. But athletic performance is a difficult and time-consuming subject to investigate, and at -present there are not enough research workers willing to turn their hand to it.