if somebody said your body was 'solid' would you take it as a compliment or an insult? to me it sounded as though they were describing me as large, (although i'm not)
younger son is "solid" and brother, he is and always was. Not fat, he's stronger than he realises.
His older bro built like a thoroughbred and also stronger than he realises.
younger son now appreciates it's not in any way shape or form an insult.