Effects Of Age And Conditioning Status On Rest And Exerc

年龄和体能状况对休息和锻炼的影响

• 批准号: 6969417
• 负责人: Samer Najjar
• 金额: --
• 依托单位: NATIONAL INSTITUTE ON AGING
• 依托单位国家: 美国
• 资助国家: 美国
• 起止时间: 至
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/6969417
• 关键词: aerobic exercise; age difference; aging; cardiac output; clinical research; exercise; gender difference; heart function; human middle age (35-64); human old age (65+); human subject; lifestyle; longitudinal human study; oxygen consumption; physical fitness; rest; young adult human (21-34); aerobic exercise; age difference; aging; cardiac output; clinical research; exercise; gender difference; heart function; human middle age (35-64); human old age (65+); human subject; lifestyle; longitudinal human study; oxygen consumption; physical fitness; rest; young adult human (21-34)

Summary:Our laboratory utilizes multiple techniques to determine the effects of age, gender and lifestyle habits on cardiovascular (CV) performance at rest and during exercise. (A) We examined whether age affects midwall systolic left ventricular (LV) performance, a more sensitive marker for determining myocardial dysfunction than standard endocardial measures. In 330 normal BLSA men (n=141) and women (n=189), those older than the median age of 50 years had smaller LV cavities, greater wall thickness, and higher endocardial fractional shortening than younger subjects. However, midwall shortening was not significantly age-related in either sex. Furthermore, the relationship between midwall shortening and end-systolic stress was similar in older versus younger groups. Thus, normative aging appears to have minimal effect on LV systolic performance whether measured at the LV endocardium or the midwall. (B) Longitudinal changes of maximal aerobic capacity (VO2max) were determined in nearly 1,400 Baltimore Longitudinal Study of Aging (BLSA) volunteers without evident cardiac disease, using mixed effects statistical analysis. Per decade, longitudinal declines in VO2max were generally greater than cross-sectional declines, especially in older decades. Gender differences in both absolute VO2max and rates of decline (men>women) are markedly attenuated when VO2max was normalized for fat-free mass rather than body weight. (C) The longitudinal decline in VO2max was determined in 42 older male endurance athletes, initially 64 (plus or minus) 6 years old. Over a mean follow-up of 7.8 years, VO2max declined by 22%, triple the decrease predicted by the baseline cross-sectional data. Within the overall sample, training status during follow-up had a major effect on the change in VO2max: the 6 men who continued to train vigorously had no significant decline in VO2max (0.28%/yr.), the 20 that trained at a lower intensity declined by 2.6% / yr, and the 14 who stopped training declined 4.6% / yr. Thus, physical activity patterns have a major impact on the long-term changes in maximal aerobic capacity in older athletes. (D) Left ventricular thickness, mass and chamber dimensions were measured in 336 healthy, normotensive adults (mean age 56+/-18 years, 200 women, 136 men) by magnetic resonance imaging (MRI). We found that the left ventricle becomes more spherical with age in normal adults because of reduced length. In women, this is associated with an increased wall thickness which offsets the decrease in length, resulting in left ventricular mass not changing with age. In men, wall thickness does not compensate for the increased sphericity, resulting in decreased left ventricular mass with age (Am J Cardiol 2002;90:1231-1236). (E) Ejection fraction (EF) acutely increases during exercise, but the EF reserve decreases with advancing age. EF is inversely related to the index of the interaction between arterial and ventricular properties, defined by the ratio of arterial elastance (EaI) to left ventricular systolic elastance (ELVI). We noninvasively characterized the arterial-ventricular coupling index EaI/ELVI and its two determinants at rest and during graded exercise in 136 healthy men and 103 healthy women (age range 21-87 years) from the Baltimore Longitudinal Study of Aging. We found that age-associated differences in EaI/ELVI occur in both genders during exercise, with less optimal coupling in older compared to younger subjects, which may help to explain the age deficit in maximal exercise EF. We also found that the mechanisms underlying the sub-optimal coupling in older adults differed between men and women (J Am Coll Cardiol. 2004;44(3):611-617).

摘要：我们的实验室利用多种技术来确定年龄，性别和生活方式习惯对静止和运动过程中心血管（CV）表现的影响。 （a）我们检查了年龄是否影响Midwall收缩性左心室（LV）性能，这是确定心肌功能障碍的更敏感的标记，而不是标准心内膜心脏措施。在330名正常BLSA男性（n = 141）和女性（n = 189）中，比中位年龄的年龄年龄较小的LV腔较小，壁厚较大，并且患有更高的心内膜小部分缩短。但是，在这种性别中，米斯壁缩短均未显着与年龄相关。此外，在较老的群体中，中间缩短缩短与终端施加压力之间的关系相似。因此，无论是在LV心内膜外测量还是Midwall测量，规范性衰老似乎对LV收缩性能具有最小的影响。 （b）使用混合效应统计分析，在不存在明显心脏病的情况下，在近1400个巴尔的摩纵向研究（BLSA）志愿者的近1,400次巴尔的摩纵向研究中确定了最大有氧能力（VO2MAX）的纵向变化。每十年，VO2MAX的纵向下降通常大于横截面下降，尤其是在年龄较大的几十年中。当Vo2max的无脂肪质量而不是体重时，绝对VO2MAX的性别差异和下降率（男性>女性）都显着减弱。 （c）在42名年长的男性耐力运动员中确定了VO2MAX的纵向下降，最初64岁（加上或负）6岁。在平均随访7。8年的时间里，VO2MAX下降了22％，三倍的下降是基线横截面数据预测的下降。在整个样本中，随访期间的训练状况对VO2MAX的变化产生了重大影响：继续大力训练的6名男子的VO2MAX没有显着下降（0.28％ /年），这20人以较低的强度下降了2.6％ /年，而停止训练的14人则下降了4.6％ /年。因此，体育活动模式对老年运动员最大有氧能力的长期变化产生了重大影响。 （d）通过磁共振成像（MRI）测量了336位健康的，正常的成年人（平均年龄56 +/- 18岁，男性，136名男性），测量了左心室厚度，质量和腔室尺寸。我们发现，由于长度降低，左心室随着正常成年人的年龄而变得更加球形。在女性中，这与壁厚的增加有关，该壁厚会抵消长度的减小，从而导致左心室质量不会随着年龄的增长而变化。在男性中，壁厚不能补偿球形的增加，导致左心室随着年龄的增长而减少（AM J Cardiol 2002; 90：1231-1236）。 （e）弹出分数（EF）在运动过程中急剧增加，但EF储备随着年龄的增长而减少。 EF与动脉和心室特性之间相互作用的指数成反比，该指标由动脉弹性（EAI）与左心收缩压弹性（ELVI）的比率定义。我们非侵入性地表征了动脉 - 室里耦合指数EAI/ELVI及其在休息时的两个决定因素，并在136名健康男性和103位健康女性（21-87岁）中进行了分级运动，来自巴尔的摩的衰老纵向研究。我们发现，与年轻受试者相比，在运动过程中，EAI/ELVI与年龄相关的EAI/ELVI差异都发生在老年人中的最佳耦合，这可能有助于解释最大运动EF的年龄不足。我们还发现，男性和女性的老年人中次优耦合的基础机制不同（J Am CollCardiol。2004; 44（3）：611-617）。