Tiredness is often associated with sleepiness, yet many people struggle to fall asleep even when they feel physically exhausted. Several factors influence sleep that go beyond mere fatigue and timing. As renowned cardiologist Dr. Alok Chopra explains, "You can feel physically exhausted, but your brain may not yet receive the biological signal for sleep. Your circadian rhythm plays a significant role in determining when your body is ready to sleep. While your body may be tired, your internal clock might not be prepared."

For the unversed, circadian rhythm refers to the natural, internal process that regulates the sleep-wake cycle and other biological processes over a roughly 24-hour period. It's often influenced by external factors such as light and temperature, and it plays a crucial role in determining when you feel awake and when you feel sleepy.

How circadian rhythm regulates sleep and wake patterns:

1. The circadian rhythm acts as a biological clock located in the hypothalamus of the brain. It responds to environmental cues, especially light, to help control sleep patterns.

2. During the day, exposure to natural light helps signal to your brain that it's time to be awake and alert. In contrast, when it gets dark, the body produces melatonin, a hormone that promotes sleepiness.

3. The circadian rhythm influences various stages of sleep, including deep sleep and REM sleep. This affects the quality of rest you get and how rejuvenated you feel upon waking.

The inability to fall asleep despite intense physical tiredness occurs because falling asleep depends on your circadian rhythm. When it is out of sync, you experience the frustrating "tired but wired" phenomenon.

"Screens in the evening interfere with melatonin production, essentially telling your brain: "IT'S NOT NIGHT YET." Work. Reels. Emails. News. Stress. You might be exhausted, but you're telling your brain that it's still daytime, and it needs to keep working," Dr. Chopra wrote in an Instagram post.

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How to fix circadian rhythm for better sleep

1. Get morning daylight

Spend time outside in natural light, especially in the morning. This helps reset your body clock and signals that it's daytime.

2. Limit light exposure at night

Reduce exposure to screens and bright lights in the evening to allow your body to produce melatonin. Consider using blue light filters on devices.

3. Consistent sleep schedule

Go to bed and wake up at the same time every day, even on weekends, to reinforce a regular sleep pattern.

4. Avoid stimulants

Limit caffeine and other stimulants, particularly in the afternoon and evening. They can interfere with falling asleep.

5. Create a calming pre-sleep routine

Engage in relaxing activities before bed, such as reading or taking a warm bath, to help signal to your body that it's time to wind down.

6. Reduce naps

If you must nap, keep it short (20-30 minutes) and avoid doing so late in the day, as this can disrupt your nighttime sleep.

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"Give your brain time to rest. Reduce screens and stimulation before bed," Dr. Chopra concluded.



Disclaimer: This content including advice provides generic information only. It is in no way a substitute for a qualified medical opinion. Always consult a specialist or your own doctor for more information. NDTV does not claim responsibility for this information.