English to Chinese Medical Medical: Health Care

Scores in the gross motor domain appear to reflect an inflation of Jane's skills given that qualitatively her movements and {tone} were not within the average range for her age

原文是一段对三个月早产儿的发育评估。其中在“粗大运动”方面，这个小朋友得分为“AVERAGE”，针对这一评分有上述说明。

在Webster上查到Tone的一个意思是：
9 a : the state of a living body or of any of its organs or parts in which the functions are healthy and performed with due vigor
b : normal tension or responsiveness to stimuli; specifically : muscular tonus
https://www.merriam-webster.com/dictionary/tone

朗文英汉中的解释：
tone -〔肌肉、皮肤等的〕结实程度，强健


在这里如何翻译合适呢？“结实程度”？