no, not a T stop... its definitely on a bus line, though i couldnt tell you which one unless i know where you think youll be coming from. would it be the washington street stop on the B line?
check out www.mbta.com
if you want to try to map it out.
the only gyms that i know of that are right on a T stop are Golds (which is right by the Kenmore Sq. stop -- next to Fenway) and Boston Athletic Club (which is just a few stops past the Washington St. stop). The most convenient one would be the Boston Athletic Club. its also the most expensive, though (like $70+ per month). it is quite nice inside and definitely has the best equipment of any club in the area (including ballys). I havent been to this Golds gym, but my gut feeling (having been to MANY Golds gyms) is that there is tons of equipment, all high quality, but not the newest, most advanced stuff. im guessing that membership is probably around $55 a month. the biggest downside to Golds is that there are a TON of stops between your apartment and Kenmore square. Its probably like a 25 minute T ride from your place to Kenmore square, and then a 5 minute walk to the gym.
your other option would be to wait till school starts and then check with me... if your study/working out schedule works with mine ur always welcome to grab a ride (especially since you live so close to me).
and of course, there is always the BC gym. if you are into weights, you are going to be VERY disappointed as there is almost no selection. if you are into cardio you might be ok as long as you dont work out at the peak times (im guessing 11-1 and 5-7 will be hard to get a machine).