the elderly who are hale and feel healthy enough to work, they should do so.
ご質問ありがとうございます。
「[元気](https://eikaiwa.dmm.com/uknow/questions/36268/)な年よりは働くべきだ」は英語で「the elderly who are hale and feel healthy enough to work, they should do so.」と言えます。
ご参考になれば幸いです。