固かた肥ごえる

ichidan verb, intransitive verb

put on moderate, firm weight; gain healthy weight (e.g. muscle); become overweight but not obese

Describes weight gain that is solid or firm, not flabby; often implies a healthy or moderate increase in body mass. The word is rare and may be encountered in older or specialized contexts.

• 最さい近きん、運うん動どうを始はじめたら、かたごえてきた気きがする。

  Lately, since I started exercising, I feel like I've put on some firm weight.

• 彼かれは以い前ぜんよりかたごえたが、肥ひ満まんではない。

  He has gained some solid weight compared to before, but he is not obese.