Era P, Schroll M, Hagerup L, Schultz-Larsen Jürgensen K
Centre of Preventive Medicine, Glostrup Hospital, University of Copenhagen, Denmark.
Gerontology. 2001 May-Jun;47(3):136-44. doi: 10.1159/000052787.
During the aging process longitudinal changes for sustained work in humans are poorly understood. Only a few longitudinal follow-up studies have been published thus far, and most of them have been based on highly selected groups, such as physical education teachers or senior athletes.
On the basis of random samples of a general population, the purpose of this study was to analyze changes in bicycle test performance in two longitudinal designs: a 10-year follow-up period from 50 to 60 years of age, using a submaximal test protocol, and another 10-year follow-up period from 70 to 80 years of age, using indirect voluntary maximal tests. In addition, the preventive value of the bicycle test results for survival at different age levels was analyzed. The subjects in the first part of the study were members of a random sample of originally 514 men and 461 women living in the Glostrup area, close to Copenhagen, Denmark, in 1964. Of these, 367 men (71.4%) and 206 women (44.7%) were tested at the age of 50 years, and 309 men and 245 women were tested 10 years later. The subjects in the second part of the study came from the same original sample. At 70 years of age 171 men and 154 women and at 80 years of age 70 men and 68 women took part in the maximal test.
The submaximal test results between the ages of 50 and 60 years showed a mean annual decline in body mass adjusted maximal power in sustained work (W/kg) of 0.54% in men and of 0.90% in women. Between the ages of 70 and 80 years, when the indirect maximal tests were applied, the annual decline in men was on average 1.79% and in women 3.03%. When the associations of submaximal test results at ages 50-60 years and the voluntary maximal test results at the higher ages were analyzed, a moderate positive correlation was observed with the results obtained at the age of 70 years. The survival analyses showed that the submaximal bicycle test results (W/kg body mass) at the age of 60 years had a predictive value for survival in women during the subsequent 10-year period. The same was true for the maximal test results obtained at the age of 70 years in men; a significantly larger proportion of men in the lowest quintile died during the subsequent 10 years than of those belonging to the higher quintiles.
The changes in body mass related maximal power in sustained work observed in this population on the basis of longitudinal studies among the age groups 50-60 and 70-80 years indicated a steeper decline at the higher ages. The decline was relatively more pronounced in women than in men. However, differences in the test protocols employed at different times limit the possibilities for overall comparisons across the data. The results of the submaximal bicycle ergometer tests in middle-aged female subjects (60 years old) had a predictive value for survival over the 10 years immediately following the test; likewise, the voluntary maximal test results at higher ages predicted survival in men.
在衰老过程中，人们对人类持续工作的纵向变化了解甚少。迄今为止，仅有少数纵向随访研究发表，且其中大多数基于高度特定的群体，如体育教师或老年运动员。
基于普通人群的随机样本，本研究旨在分析两种纵向设计中自行车测试表现的变化：一是从50岁到60岁的10年随访期，采用次极量测试方案；另一是从70岁到80岁的10年随访期，采用间接自愿最大测试。此外，还分析了自行车测试结果对不同年龄水平生存率的预防价值。研究第一部分的受试者是1964年居住在丹麦哥本哈根附近格罗斯特鲁普地区的514名男性和461名女性随机样本的成员。其中，367名男性（71.4%）和206名女性（44.7%）在50岁时接受了测试，10年后有309名男性和245名女性接受了测试。研究第二部分的受试者来自相同的原始样本。70岁时，171名男性和154名女性参与了最大测试；80岁时，70名男性和68名女性参与了最大测试。
50至60岁之间的次极量测试结果显示，持续工作中按体重调整的最大力量（W/kg），男性平均每年下降0.54%，女性平均每年下降0.90%。在70至80岁之间，采用间接最大测试时，男性平均每年下降1.79%，女性平均每年下降3.03%。当分析50至60岁的次极量测试结果与更高年龄的自愿最大测试结果之间的关联时，观察到与70岁时获得的结果存在中度正相关。生存分析表明，60岁时的次极量自行车测试结果（W/kg体重）对女性随后10年的生存具有预测价值。70岁时男性的最大测试结果也是如此；在随后10年中，最低五分位数组的男性死亡比例明显高于较高五分位数组的男性。
基于50 - 60岁和70 - 80岁年龄组的纵向研究，该人群中观察到的持续工作中与体重相关的最大力量变化表明，在较高年龄时下降更为陡峭。女性的下降相对男性更为明显。然而，不同时间采用的测试方案差异限制了对整个数据进行全面比较的可能性。中年女性受试者（60岁）的次极量自行车测力计测试结果对测试后紧接着的10年生存具有预测价值；同样，较高年龄的自愿最大测试结果可预测男性的生存情况。
