The typical response to feeling tired or lethargic is usually one of the following: reach for a coffee or energy drink or sit down and relax. Of course, none of those things will do much for your overall energy levels, and they could lead to potential health risks and complications.
If you need a brief pick-me-up or an overall boost in energy levels, the natural method is best. It involves getting more sleep, identifying and coping with stressors, being more active, and knowing how to make the proper food choices. Doing those things can lead to more energy at any age and provide some sustainability for you to get out and enjoy yourself.