It takes only 10- 15 minutes of your time and can change the way you look and most importantly FEEL in just a matter of days. You can do it on a treadmill, on a bike, stair climber, outside (around the block), up a hill, in the swimming pool, pretty much what I am trying to say is interval training can be done anywhere (so no excuses).
It's 60 seconds of "all you got" followed by 30-60 seconds of a moderate pace (always make sure you are warm-up before starting). Going from aerobic to anaerobic allows the body to burn more calories in a shorter amount of time and releases all the "feel good" chemicals that can help with depression, anxiety, insomnia, and much more.
In all, if you are a person who just doesn't have the time or focus to sit in the gym all day, try interval training and see how you can reshape your body and possibly your life!