With regard to aging, resistance may or may not be futile. In either case, it makes sense to attend to the various matters which are implied by the aging process at this stage of life.
Most people who go through the process of planning for end-of-life issues find the experience valuable. We know that lifespans are continuing to increase, but regardless of your present state of health, the beginning of the later stages of life is the time to make plans for what you know to be inevitable. In addition to the list of standard items below, you may wish to look into prearranging (and even prepaying) for your funeral. This will be one less burden for your survivors to deal with. Another important chore is to make sure that all of your vital documents are organized intelligibly, with lists of their locations. Here is a link to a documents organizer to get you started.
Long-term care can become a significant issue in the later stages of life. You should determine whether obtaining insurance for this contingency is appropriate for you. Don't delay in the hopes that prices will come down -- the cost of this insurance only goes up as you age.
Please review the following list and consult the appropriate professionals to help you complete your planning as appropriate for your own circumstances.