Before you reach that cup of coffee or that bar of chocolate, which will probably only give you an energy boost for a couple of minutes and your probably feel worse after it as your body crashes again and you end up at square one again.
Here is a breathing exercise you can use as a natural energy booster, find a place where you can relax either on a bed or upright in a chair, because this exercise can bring on a feeling of dizziness to the beginner trying it out please dont try to do it in a standing position or whilst in your car!
Firstly get yourself comfortable position whether suiting in a chair or lying on your bed and keep your back in straight position so nothing is effecting the air flow. Close your mouth and start to breathe in and out through your nose in a rapid fashion, try to breath about 2-3 inhalations a second for about 10 seconds. I know that at the start it will probably feel awkward and you will fill your muscle are having to work harder (this is good for strengthening your diaphragm) but the more you practice it youll find it easier to do and when you feel comfortable and gotten over the dizzy sensations you can then increase the length of time...