وَعَنْ عَائِشَةَ رَضِيَ اللَّهُ عَنْهَا قَالَتْ: كَانَ رَسُولُ اللَّهِ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ يَصُومُ الِاثْنَيْنِ وَالْخَمِيس. رَوَاهُ التِّرْمِذِيّ وَالنَّسَائِيّ

‘Amir b. Mas'ud reported God’s messenger as saying, “Fasting in winter is booty gained without trouble.”**Literally, 'the cold booty.' The idea is that in winter one does not suffer from hunger and thirst as in summer.Ahmad and Tirmidhi transmitted it, the latter saying this is a mursal tradition.