All perfect praise be to Allaah, The Lord of the Worlds. I testify that there is none worthy of worship except Allaah, and that Muhammad, sallallaahu ‘alayhi wa sallam, is His Slave and Messenger.
The Fataawa to which we have referred you adequately describe the Islamic Hijab and the requirements that must be fulfilled for it. We mention the Fatwa numbers again here: 83702, 257593 and 83983. Loose-fitting sports pants, regardless of how loose-fitting they may be, do not meet those requirements of the Hijab.
It is sinful for a woman to wear such pants in front of non-Mahram men, especially if she is exercising in their presence. This is a major cause of Fitnah (temptation). Please refer to Fatwa 91237. Education in which genders are mixed in a forbidden manner is impermissible. You are advised to look for another university to accomplish your objective and finish your studies while avoiding committing such a prohibited act.
If you cannot find any and there is a necessity or real need for completing your studies and you cannot drop this subject in any given way or obtain credit for it in another way without committing this prohibited act, then there is no harm in this case to continue your studies in proportion to the necessity, and your attending of this college should also be limited to the proportion of necessity only. Therefore, you are allowed to wear loose-fitting pants also in proportion to the necessity. Once the necessity ceases to exist, you should leave the campus and wear your Islamic Hijab.
Allaah Knows best.