If you get rejected the first time there are plenty of things to do to increase your chances of admission for the 2nd time:
a) Talk to the schools that rejected you. Ask how can you improve your application.
b) If MCAT was your problem, you can study more and retake. If GPA then you take (or retake) some courses to make it stronger.
c) In the 1 year time that you have there are plenty of community opportunities available : Donate your time and make your ECs much much stronger.
d) Get a job in the medical field or volunteer.
e) Get better LORs from employers, orgs that you were involved with etc.