All perfect praise be to Allah the Lord of the Worlds. May His peace and blessings be upon our Prophet Mohammad and upon all his family and companions.
Islam encourages Muslims to engage in physical activities and sports that promote physical fitness, health, and skill development. However, it prohibits any activities that can cause harm to the body, especially hitting or striking on the face and head, as these actions can lead to serious injuries, including concussions or even death.
The Prophet Mohammad, peace be upon him, prohibited striking or hitting on the face. He said: "When any of you fights, he must avoid the face." {Transmitted by Bukhari}.
The reason behind this prohibition, as explained by Badr al-Din al-Ayni, may Allah have mercy upon him, based on the narration of Imam An-Nawawi, may Allah have mercy upon him, is that : "The face is a delicate area where many vital and sensitive organs are located. Striking the face could lead to severe harm, disfigurement, or even the loss of these important organs. The face is an area that is particularly susceptible to damage, and the Prophet, peace be upon him, prohibited striking it to protect the well-being and dignity of individuals." {Umdat Al-Qari Shareh Sahih Al-Bukhari, Vol.13, Page, 116}.
In conclusion, one of the principles of Islamic jurisprudence is that if harm is established, the prohibition is also established. Striking on the face and head falls under this principle. Its prohibition is established in Islamic law when it results in harm or injury to the person being struck. However, if necessary precautions are taken to prevent harm, such as wearing protective gear like helmets and clothing that shields against blows that could cause harm to any part of the body, then there is no sin in engaging in these sports. And Allah the Almighty knows best.