Doing exercise in a gym where there is music
Question

                What is the ruling on exercising in a gym where there is music? Please note that I have advised those who are in charge but they did not act upon my advice. Now I have started to use an mp3 player whilst I am exercising.
Praise be to Allah.
    Firstly: 

    It is not permissible to listen to music, whether in a gym or 
    elsewhere, because of a great deal of evidence which states that it is 
    haraam to listen to musical instruments. See the answer to question no. 
    5000. 

    Secondly: 

    The fact that there is music in the gym is an evil which must 
    be denounced. It is not sufficient just to put on earphones to block the 
    sound or distract oneself by listening to something permissible. Rather if 
    denouncing it verbally does not work, there remains the option of denouncing 
    it in one’s heart, which can only be achieved by going away from the evil 
    and leaving the place where it is happening, so long as one is able to do 
    that. 

    The Prophet  (peace and blessings of Allaah be upon him) 
    said: “Whoever among you sees an evil action, then let him change it with 
    his hand [by taking action]; if he cannot, then with his tongue [by speaking 
    out]; and if he cannot, then with his heart – and that is the weakest of 
    faith.” 

    Narrated by Muslim (49). 

    The fact that it is obligatory to leave the place where evil 
    is being committed is also indicated by the verse in which Allaah says 
    (interpretation of the meaning): 
“And it has 
    already been revealed to you in the Book (this Qur’aan) that when you hear 
    the Verses of Allaah being denied and mocked at, then sit not with them, 
    until they engage in a talk other than that; (but if you stayed with them) 
    certainly in that case you would be like them. Surely, Allaah will collect 
    the hypocrites and disbelievers all together in Hell”
[al-Nisa’ 
    4:140]
al-Qurtubi (may Allaah have 
    mercy on him) said: The words of Allaah, “then sit not with them, until 
    they engage in a talk other than that” mean, something other than kufr 
    (disbelief). “(But if you stayed with them) certainly in that case you 
    would be like them” – this indicates that it is obligatory to avoid 
    people of sin if they are openly committing evil, because the one who does 
    not avoid them is approving of their deeds, and approving of kufr is also 
    kufr. Allaah says “(but if you stayed with them) certainly in that case 
    you would be like them”, so everyone who sits in a gathering where sin 
    is committed and does not denounce them will share the burden of sin with 
    them.  
They should be denounced if 
    they speak of sin or commit sin; if one cannot denounce them then he should 
    leave them so that he will not be one of those mentioned in this verse. 
It was narrated that ‘Umar 
    ibn ‘Abd al-‘Azeez caught some people who were drinking alcohol, and it was 
    said to him that one of the people present was fasting. He had the 
    punishment carried out on him too, and he recited this verse: “(but if 
    you stayed with them) certainly in that case you would be like them”, 
    i.e., approval of sin is also a sin. End quote. 
Al-Jassaas said in 
    Ahkaam al-Qur’aan (2/407): This verse indicates that it is obligatory to 
    denounce evil to the one who does it, and part of denouncing it is showing 
    one’s dislike of it if it is not possible to remove it, and not sitting with 
    the one who does it, and leaving him until he stops it and does something 
    else. End quote.
Shaykh Ibn Baaz (may Allaah 
    have mercy on him) said: Denouncing in one's heart is obligatory for 
    everyone, which means hating the evil and leaving the people if one is 
    unable to change it with one's words or actions, because Allaah says 
    (interpretation of the meaning): 
“And when you (Muhammad
    صلى الله عليه وسلم) see those who engage 
    in a false conversation about Our Verses (of the Qur’aan) by mocking at 
    them, stay away from them till they turn to another topic. And if Shaytaan 
    (Satan) causes you to forget, then after the remembrance sit not you in the 
    company of those people who are the Zaalimoon (polytheists and wrongdoers)”
[al-An’aam 6:68]
End quote from al-Durar 
    al-Saniyyah fi’l-Ajwabah al-Najdiyyah (16/142). 

    To sum up, you must denounce this evil and advise those who 
    are in charge of this gym. If they respond, then praise be to Allaah, and if 
    they do not respond then look for another gym, and do not share in the sin. 

    And Allaah knows best.