Hi Lavanya,
Its quite natural to feel sleepy in the afternoons after a tiring day's work...reading books would make me feel more sleepy. I started sitting with my son for his studies say from 3-5. Thanks to my son

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I started noticing that once i lie down on the sofa for a while to relax I end up in sleeping. If u have the same tendency of mine, better avoid lying down even for a while.