Eat a light lunch. Exercise in any manner for an hour. Sleep for 8 hrs every night. Use appropriately timed coffee and tea breaks. Develop a hobby. Engange in mentally stimulating tasks and games. Use power naps.  Cut back on drinking and drugs. If everything fails, get some tests done. CBC and Thyroid function.

Staying active throughout the day requires a number of factors For example, how is your lifestyle? Is it relaxed or stressful? How's your work atmosphere treating you? Do you stay alone or are you surrounded by your loved ones to support you? How's your sleep routine? Is there an adequate uninterrupted night sleep every day? How is your hormonal status? Do you have and gynaecological or hormonal disturbances? Do you have any other problems like long standing health issues or any other stresses regarding studies, career, money or relationship How active are you? Sedentary lifestyle leads to laziness..  a regular exercise regime is helpful Last but not the least, what's your nutritional status? Anemia and other nutritional deficiencies will often make you feel tired and weak. Lastly, the most important question is, are these symptoms: tiredness and dullness; so disturbing and so severe that they are compromising your day to day activities? Are these symptoms bothering you so much that you are not able to work or enjoy life properly? If that's the case, please take help from a professional. Because, these symptoms can be completely resolved with professional help.