- Waking up in the wrong phase: Your sleep is split into cycles, and you might've woken up during the non-REM stage, which is a state of very deep sleep. Try to shoot for waking up during a REM phase, because then your body will be better prepared to wake up.
- Poor quality of sleep: It doesn't matter how long you sleep for if you're it's low-quality rest; you'll just wake up tired. Poor-quality sleep can be caused by factors such as sleeping with a pet, drinking caffeinated beverages late in the day, or having too much noise in the background.
- Medication hangover: The effects of certain medications that cause drowsiness can linger until the next morning. Check with your doctor to see if you can adjust the dosage or change medications.
- Medical condition: Certain medical conditions like sleep apnea can disrupt your night's rest. Disorders like depression can also cause you feel drained of energy, a symptom that can contribute to your grogginess.
- Your body clock is not in sync: If you've been keeping an erratic sleep schedule, then your body will probably need time to adjust to waking up at a certain time during the morning. Try to make a more regular schedule, and you'll probably see a difference in how you feel in the morning.