Exercise 10 minutes daily (or at least 3-5x a week) as soon as you wake up and before you hit the shower. Do intervals. Out of the 10 minutes, two have to be all out and intense. You can do a treadmill, elliptical, or as I often do at home: jumping jacks and running in place (no, seriously). Also, listen to your favorite, upbeat music.
Benefits:
* exercise is generally good for the frontal cortex, what helps you focus and get things done [1]
* exercising in the morning will put you in a more positive mood, helping to reduce stress; by reducing stress, you feel more energetic, you feel less hungry and crave less crappy food, therefore you prevent the systematic downward spiral that comes with it and you lose weight.
* because you exercise in the morning, you burn more fat [2]
* adding music is great for your dopamine levels: [3]
* intensity (anaerobic exercise) is more important than duration and frequency [4]
I ran into this routine because I always have a hard time waking up in the morning (not so much anymore) and was always late to work. But knowing from previous experience that working out intensely in the morning helped with my energy level and focus, I did 10-15 minutes and found that it's all that I needed. In a bit over a month I've lost like 9lbs, I eat better, get less tired at work and can focus for longer periods of time.
I hope to put my experiences into a blog post series soon.
[1] http://well.blogs.nytimes.com/2012/02/22/how-exercise-fuels-... + other research. Also, read the Willpower Instinct (for a summary of lots of research)
[2] http://www.sciencedaily.com/releases/2013/01/130124091425.ht... This is the first source I could find, but I've known about similar research for years.
[3] http://phenomena.nationalgeographic.com/2013/04/11/why-does-...
[4] http://www.ncbi.nlm.nih.gov/pubmed/3529283
If you're already very fit, a friend of mine pointed out this routine recently which is more intense than the one I propose: http://healthland.time.com/2012/09/04/we-tried-this-fast-and...
Edited: 1) format 2) removed superfluous phrases