Sayyiduna Hamzah bin Amr (may Allah be pleased with him) said: I said: O Messenger of Allah, I am an owner of riding animals; I look after them, travel on them and hire them out. Sometimes this month comes upon me, and I have strength and I am young. O Messenger of Allah, fasting is easier for me than delaying it so that it remains a debt upon me. O Messenger of Allah, shall I fast, which is greater for my reward, or shall I break the fast? He (peace and blessings be upon him) said: "O Hamzah, whichever of those you wish."
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الصيام / 8143