A Guide to the Good Life: The Ancient Art of Stoic Joy - William B. Irvine
Not only a description of the Stoic philosophy, which is, unfortunately, not very well known today, but also a great practical guide to a variety of techniques that can be included into daily activities easily, and will increase happiness.
For the body:
Overcoming Gravity: A Systematic Approach to Gymnastics and Bodyweight Strength - Steven Low
As I'm growing older (turned 40 last year), I'm no longer inclined to exercise with very heavy weights and was looking into replacing most of the barbell/dumbell exercises in my routine with bodyweight exercise. The book is a great encyclopedia of exercise that can be performed without or with minimal equipment. There are progressions, advice on creating routines, on injury prevention and management and a lot more. There is also a subreddit for those who follow the book http://www.reddit.com/r/overcominggravity
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