“. . . . the greatest source of unhappiness in work is risk aversion — which leads to stagnation and resentment,” says Howard Stevenson, a professor (emeritus) at Harvard Business School (http://www.npr.org/2016/03/17/469822644/8-ways-you-can-survive-and-thrive-in-midlife). I would also say the same about life in general. Not that joining a tai chi group class or taking private lessons are risky. But you still have to get up and out of your inertia to start.