[Mugala]

try OnPlayerTakeDamage for only fist.

PHP Code:

public public OnPlayerTakeDamage(playerid, issuerid, Float: amount, weaponid, bodypart)
{
    if(weaponid == 0)
    {
        new Float:HP;
        GetPlayerHealth(playerid, HP);
        SetPlayerHealth(playerid, HP);
    }
    return 1;
}