If you feel tired and drained, you are not alone. "Lack of energy" is very popular nowadays.
From TCM point of view, sleeping recharges the body, and is important in maintaining a balance of yin and yang within it. If you sleep too little, the Yin energy will decline beyond the normal range. When Yin energy becomes inadequate, the Yang will predominate. Sleep early and exercise regularly will enhance Qi and blood circulation.
Chinese medicine practitioners divide the day into yin times (11 a.m. to 11 p.m.) and yang times (11 p.m. to 11 a.m.). Each contains six two-hour periods, each one best for certain activities.
TCM recommends going to bed at the yin predominate time (night) while waking up at the yang predominate time (day). The ideal time to sleep in accordance to the meridian clock is from 11pm to 5am. As such, try to go to bed before 11 pm. By falling asleep before yang time begins at 11 p.m., sleepers are able to get good rest and wake up refreshed and rewarded with increased energy.