Centre committees

I am the Hon Secretary of the East Kent Centre, and although we have a good membership we are already four members short on our current committee and in October we will have four members who will not be standing for reelection. Has any Centre come up with an innovative ideas to try to encourage more members to stand for their committee ? It is difficult because members either are working more hrs and don't feel they have the time or they are retired and don't want to tie themselves down. We also have a core group of regulars who have been there and done it and want to have a rest :) Anybody who has seen  a similar situation and have changed something to encourage more members, I would love to hear what was done..............thanks