tenacious
having or manifesting great force or power (as in acting or resisting); holding fast; characterized by keeping a firm hold; highly retentive; pertinacious, stubborn or obstinate; persistent in adhering to something; holding together (Webster’s New Universal Unabridged Dictionary)
determined, dogged, fast, firm, persistent, secure, strong, stubborn, sturdy, tough
One of my favorite t-shirts as a kid had a cartoon drawing of an ant dragging an elephant by its trunk up a hill with the words, “Where there’s a will, there’s a way!” A perfect illustration of being tenacious. This dogged determination will no doubt come in handy in the last third of our lives. When we can’t see or hear as well and our bodies won’t listen. Being tenacious allows us to hang in there no matter what gives out or breaks down.