This study compared ultrasound characteristics in youth, younger adults, and older adults using two different methods of analysis: based on clusters of pixel concentration of the grayscale (i.e. EI bands) and the traditionally calculated echo intensity mean. Forty-four healthy youth (13.3 ± 1.4 y), 22 younger adults (31.8 ± 10.1 y) and 53 older adults (66.7 ± 4.6 y) volunteered for the assessment of rectus femoris EI via ultrasonography. Pixel concentration (i.e. EI bands) was calculated in intervals of 0–50, 51–100, 101–150, 151–200, and 201–255 of the gray scale, while EI mean was determined as the average pixels from 0 to 255. EI_0–50 significantly decreased with group age, while EI_{51–100, 101–150, 151–200, 201–255} and EI mean increased (P < 0.001). The differences between groups were greater using EI_0–50 compared to the EI mean (i.e. EI_0–50: youth = ~353% and younger adults = ~251% > older adults; whereas EI mean: youth = ~46% and younger adults = 29% < older adults). These results potentially indicate that EI bands method offer different information than the EI mean method. In addition, EI bands may be a promising approach to understand tissue-specific adaptations to physical training and neuromuscular diseases, yet future studies should validate this method.

这项研究使用两种不同的分析方法比较了青年，年轻人和老年人的超声特征：基于灰度（即EI波段）的像素浓度簇和传统计算的回波强度平均值。四十四名健康的青年（13.3±1.4 y），22名较年轻的成年人（31.8±10.1 y）和53名老年人（66.7±4.6 y）自愿通过超声检查评估了股直肌EI。像素浓度（即EI波段）的计算间隔为灰度的0-50、51-100、101-150、151-200和201-255，而EI平均值被确定为0到255之间的平均像素。EI _{0 – 50}随着年龄的增长而显着下降，而EI _{51 – 100、101 –150、151 – 200、201 – 255}和EI平均值增加（P  <0.001）。与EI平均值相比，使用EI _{0 – 50}组之间的差异更大（即EI _{0 – 50：}青年=〜353％，而年轻成年人=〜251％>成年人；而EI平均值：青年=〜46％和年轻成人= 29％<老年人）。这些结果可能表明EI波段方法提供的信息不同于EI均值方法。此外，EI频段可能是一种了解组织对体育锻炼和神经肌肉疾病的适应性的有前途的方法，但是未来的研究应验证这种方法。