What is the ruling on sports, especially combat sports?

A translation of this fatwa from Naseem al-Sham

Question

Peace be upon you. What is the ruling on wrestling and similar sports such as karate, boxing, judo, and the like? Is it permissible to train in these combat sports and to attend competitions? Is it permissible to train in order to maintaining one physique, bearing in mind that in boxing, for example, you have to strike your brother’s face? If both participants consent to this in training and in competition, it is thus permissible? Furthermore, what do you say about freestyle wrestling and Greco-Roman wrestling, bearing in mind that they do not cover their nakedness (ʿawrah) and they lie on top of each other? Please advise us. May Allah reward you.

Answer (Imam Rushdī Salīm al-Qalam)

Praise be to Allah, and He suffices, and peace be upon al-Muṣṭafā.
To proceed: Playing sports in order to invigorate the body and strengthen it is commendable in the Revealed Law (Sharīʿah). However, opening the door fully to causing harm, such as striking the face, breaking ribs, exposing the private parts, and bowing to other than Allah, that is ḥarām.

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