In Japan, the concept of ‘Inemuri’ has gained attention as a unique practice of napping that may sound unusual to many.
The term directly translates to ‘sleeping while present’ and refers to the act of napping in public or during work hours. Often seen in offices, on trains, or in other public spaces, the Inemuri nap is considered a cultural norm rather than a sign of laziness. This practice has sparked curiosity around whether it offers a solution for those who find themselves sleep-deprived.
With many people struggling to get adequate rest, the idea of napping strategically to boost productivity and mental clarity is gaining popularity. But can Inemuri truly help improve energy levels, or is it just a fleeting solution for a bigger sleep problem?
Dr Jagadish Hiremath, public health intellectual, tells , “Inemuri naps can offer short-term relief for sleep-deprived individuals by allowing brief moments of rest during active participation in daily routines, such as meetings or public commuting. Unlike traditional naps taken in a private setting, Inemuri emphasises adaptability — individuals remain mentally prepared to re-engage with their surroundings quickly.”
Dr Hiremath adds that inemuri usually involves light, non-REM sleep stages, which can improve alertness and cognitive function without inducing sleep inertia (the grogginess experienced after waking from deep sleep). “A study published in Nature Neuroscience shows that even short periods of light sleep can enhance memory consolidation and focus,” he says.
While regular naps aim for deeper restorative benefits, Dr Hiremath notes, Inemuri prioritises practicality, making it less effective for long-term recovery from significant sleep debt.
The effectiveness of Inemuri naps largely depends on their duration and timing. “Research suggests that naps lasting 10–20 minutes are ideal for improving alertness and reducing fatigue without disrupting nighttime sleep. Short naps help rejuvenate the body and mind, providing a quick boost of energy without the risk of feeling groggy afterward,” states Dr Hiremath.
However, longer naps, ranging from 30 to 90 minutes, risk entering deeper sleep stages, which can lead to sleep inertia. Dr Hiremath states, “Sleep inertia refers to the groggy, disoriented feeling some people experience after waking from a deep sleep. This can hinder the benefits of napping and make it harder to regain full alertness.”
Inemuri’s cultural practice allows for varying nap lengths, from just a few minutes to longer periods, depending on the individual’s environment and schedule. The practice is quite flexible, allowing people to adjust the duration to suit their needs. However, it is most effective when aligned with the body’s natural circadian rhythm, particularly during mid-afternoon energy slumps.