Really respect your initiative! DBAC is open from 6 am to 10 pm on weekdays during the spring/summer. Normally, the student card allows you entry into the Athletic Centre because as part of our student fees, everyone has a DBAC membership (but not everyone has a Pulse membership which is extra). DBAC membership is enough to use the changerooms/showers. If you are entering first year this year, I'm not sure if you will have access because technically some first-years may not have paid their tuition fees since the deadline has not arrived yet - Sept 1st.
As long as the barcode is present on your student card and you scan it at the turnstile, it should let you through - unless they have programmed it not let students cards with the 2012/2013 year through.
If that is the case then you can gain entry into DBAC without going through the turnstile by entering the adjacent building, IWC which is connected to DBAC.
Once you are in IWC foyer. Take a left into a really big hallway which overlooks a gymnasium. Now you are in DBAC (Maroon Hallway). Follow the directions to go into the main atrium. You will have to go downstairs. The changerooms are in between the squash courts and the service desk.
Hope that helps
DBAC Hours of Operation
http://www.marauders.ca/sports/2011/...?path=services