There's nothing wrong with having a short sleep around the middle of the day, in fact it offers numerous health benefits.
A longstanding tradition in southern Europe, the siesta or midday nap is frequently derided in our modern working environment. But power napping is actually very good for you. It increases concentration, thereby improving performance. It helps prevent heart disease, promotes the concentration of serotonin in the blood contributing to an improved mood. Most people struggle with tiredness and a lack of concentration around midday due to the normal human biorhythm. A power nap lasting between 20 and 30 minutes, but definitely no longer than an hour, can help. Power napping in the office is also an option – or outside in a near park.