If you haven’t already renewed your Club and TI memberships, you should not be participating in club training sessions (unless you are a signed in Guest). Both Club and TI memberships can be taken out here.
Full Annual TI membership provides insurance for racing and training, the benefits of which have recently been enhanced see here. Associate TI membership allows for training only.
It is worth noting the One Day licence rates for 2014 have increased to €10 for Duathlon and Aquathlon, and €20 for Triathlon, so if you thing you may do even 2 events, Full TI membership is the way to go. Full Club and TI membership works out at less than €5 per month.