Reading, after a certain age, diverts the mind too much from its creative pursuits. Any man who reads too much and uses his own brain too little falls into lazy habits of thinking.
Albert Einstein
If you have that much free time, why not learn a language, or do an online course or bring a cheap guitar or small keyboard into work, and leave it in the truck. Or buy an electronic chess board and challenge the computer…this can become seriously addictive. Save the reading for bedtime.
Or bring some running gear in a gym bag, and lock the charabang up and go for a run around the area. It is amazing how your outlook changes during and after a good run. No books or headphones required.