Hadithcore
Mishkat al-Masabih, 1099

Ibn ‘Abbas reported God’s Messenger as saying, ‘‘The best of you are those whose shoulders give least annoyance in prayer." Abu Dawud transmitted it.

وَعَنِ ابْنِ عَبَّاسٍ قَالَ: قَالَ رَسُولُ اللَّهِ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ: «خِيَارُكُمْ أَلْيَنُكُمْ مَنَاكِبَ فِي الصَّلَاة» . رَوَاهُ أَبُو دَاوُد

References1 variant
In-Book Reference
Book 4, Hadith 516