Abu Bakr b. 'Abd al-Rahman reported that he had heard Abu Huraira say that the Messenger of Allah (ﷺ) said like it, but he substituted" the aged" for 'the infirm".
Sahih Muslim Book 4, Hadith 211
← Previous Hadith The Messenger of Allah (ﷺ) said: When any one of you leads people in prayer, he must shorten it for among them are the weak, the infirm and those who have business to attend.

Sahih Muslim Book 4, Hadith 210 Next Hadith → The Apostle of Allah (ﷺ) said to him: Lead your people in prayer. I said: Messenger of Allah. I perceive something (disturbing) in my soul. He (the Holy Prophet) asked me to draw near him and making me sit down in front of him he placed his hand on my breast between my nipples. and then, telling me to turn round, he placed it on my back between my shoulders. He then said: Act as an Imam for your people. He who acts as Imam of the people, he must be brief, for among them are the aged, among them are the sick, among them are the weak, and among them are the people who have business to attend. But when any of you prays alone, he may pray as he likes.

Sahih Muslim Book 4, Hadith 212