Be flexible with your prayers; if you are unable to stand due to an illness or injury then it is permissible for you to sit instead.

The hadith narrated by Abdullah b. Shaqiq al-'Uqaili tells us that the Prophet Muhammad PBUH used to pray both in a standing and sitting position, and when he began his prayer either way, he would bow down while still in that same position. This teaches us that we should be flexible with our prayers; if we are unable to stand due to an illness or injury, then it is permissible for us to sit instead. We should also remember that no matter how we start our prayer, when it comes time for bowing down we must do so while still maintaining whatever posture we began with. This hadith also reminds us of the importance of being humble before Allah SWT; even though the Prophet was one of the most important people on earth at his time, he still bowed down humbly before Allah SWT just like everyone else does during their prayers.