Endorphins are chemicals called neurotransmitters that your body produces and that interact with opiate receptors in the brain. One way to get a healthy dose is through vigorous exercise. You have to get your heart rate up, a leisurely stroll isn't enough. Endorphins help manage stress, relieve pain, and produce feelings of euphoria or happiness, Endorphins are responsible for what is commonly referred to as the "Runner's High"
Some Studies have shown that vigorous exercise 4-5 days a week was as effective or even more effective than some commonly used antidepressant medications. (But do not make the decision to stop your medication without consulting your own healthcare provider)
Another way exercise helps reduce stress is quite simply that it improves blood flow to the brain, and a healthier brain can more easily process information. Exercise, so long as it's separated from bedtime by at least 2 hours helps you sleep better, and improving sleep helps reduce stress. Exercise improves blood flow to every part of the body, and a healthier body can more easily cope with stress. For these benefits even a brisk walk will help.
Lastly Exercise is fun --- or it can be. You don't have to "work" out, you can play. If getting on a treadmill makes you feel like a hamster on a wheel, you can play tennis or racquetball. I got the best "work" out when there was an underwater hockey group in my area, and I had, like almost everyone, never heard of it before, but I had a blast. If you are bored with your exercise routine, try Zumba, kickboxing, martial arts, team, or individual sports, hiking, biking there are endless possibilities. Having fun reduces stress.
So where do you start? If you are currently doing nothing, and you are healthy with no medical activity restrictions, start by walking, listening to fast - paced music will make you move faster and can nearly double your calories burned, and helps combat boredom. All you need is a pair of comfortable shoes and you can start right now. You can start by getting up just 10 minutes earlier and taking a quick walk before you start the day, and work your way up from there. You can check out local health clubs and see what they offer that you will have fun doing. Meetup is a great way to find people with a common interest (biking, soccer, tennis et. c) NO time, not a problem, Exercise makes the brain work more efficiently so you'll find that the time is actually gained in the form of getting things done more efficiently -- another great stress relief!