Sleep Quality
Sleep quality score reflects indicators of your sleep health derived from your physiological readings — including heart rate patterns, HRV, and breathing regularity. Quality sleep is foundational to virtually every aspect of health: immunity, cognition, mood, weight, and cardiovascular function. The WHO classifies poor sleep as a global health epidemic.
Normal range
How Vsense measures it
Vsense estimates sleep quality using cardiovascular and autonomic patterns observable during the scan — people with poor recent sleep show distinctive HRV, heart rate, and breathing patterns.
How it's scored
70–100: Good sleep quality. 50–69: Moderate — room for improvement. Below 50: Poor sleep quality affecting your health. Even one night of poor sleep measurably impairs cognitive function, mood, and immune response.
What a high reading means
A high sleep quality score is excellent. Good sleep supports memory consolidation, muscle recovery, hormone balance, immune function, and emotional regulation. Deep sleep (slow-wave sleep) restores the body; REM sleep processes emotions and consolidates memory.
What a low reading means
Poor sleep quality is one of the most damaging yet overlooked health risks. It raises cortisol, disrupts appetite hormones (making weight gain easier), impairs glucose regulation, increases blood pressure, and accelerates cognitive decline. Chronic sleep deprivation is associated with every major chronic disease.
How to improve it
Exercise
- Regular exercise (even 20 minutes of walking) improves sleep quality significantly — but avoid intense exercise within 2 hours of bedtime
- Morning sunlight exposure combined with exercise powerfully anchors your circadian rhythm
- Yoga and stretching before bed reduce cortisol and prepare the body for sleep
- Tai chi has strong evidence for improving sleep quality in all age groups
- Resistance training 3× per week improves sleep duration and deep sleep percentage
Diet
- Tart cherry juice (240ml before bed) is one of the few foods with clinical evidence for improving sleep — rich in natural melatonin
- Warm milk or chamomile tea contains compounds (tryptophan, glycine) that promote sleep
- Magnesium-rich foods (pumpkin seeds, almonds, spinach) relax muscles and support sleep
- Avoid caffeine after 2pm — it has a half-life of 5–7 hours and disrupts deep sleep even if you fall asleep fine
- Avoid alcohol near bedtime — it fragments sleep in the second half of the night and suppresses REM sleep
- A small carbohydrate snack (banana, oatmeal) 1 hour before bed can help
Lifestyle
- Keep a consistent sleep/wake schedule — even on weekends. This is the single most impactful sleep habit
- Keep your bedroom dark, cool (16–19°C / 61–67°F), and quiet
- Avoid screens 1 hour before bed — blue light suppresses melatonin by up to 50%
- Use your bed only for sleep (and intimacy) — not work or screens
- Create a 20–30 minute wind-down routine: reading, gentle stretching, or bath
- Manage stress during the day so it doesn't follow you to bed
- Limit naps to 20 minutes and avoid after 3pm
Natural remedies
- Lavender essential oil (on pillow or diffused) reduces anxiety and improves sleep quality
- Progressive muscle relaxation (tense and release each muscle group) is clinically proven for insomnia
- 4-7-8 breathing lying in bed — slows your nervous system within minutes
- Ashwagandha (300–600mg KSM-66 extract) has clinical evidence for reducing sleep onset time and improving sleep quality
- Valerian root tea or supplements may help with mild insomnia
- Magnesium glycinate (300–400mg before bed) is one of the most evidence-backed sleep supplements
Frequently asked questions
How many hours of sleep do I actually need?
Adults need 7–9 hours. Less than 6 or more than 9 hours is associated with worse health outcomes. Quality matters as much as quantity — 7 hours of deep, uninterrupted sleep beats 9 hours of fragmented sleep.
Why do I wake up at 3am?
Common causes include: cortisol spike (stress), blood sugar drop, alcohol metabolism, temperature discomfort, or sleep apnea. Waking briefly is normal — struggling to fall back asleep suggests poor sleep hygiene or underlying issues.
Does napping help?
A 20-minute nap (before 3pm) boosts alertness and mood without disrupting night sleep. Longer naps (90 min = full sleep cycle) can be beneficial. Avoid napping after 4pm.
How does poor sleep affect my other vitals?
Poor sleep raises resting heart rate, lowers HRV, elevates blood pressure, increases cortisol, raises blood sugar, and suppresses immune function — virtually every vital is impacted within just one night of poor sleep.
What is sleep apnea?
Sleep apnea is when breathing repeatedly stops and starts during sleep. Symptoms include loud snoring, gasping, and waking unrefreshed. It significantly drops SpO2 and HRV overnight and is a major cardiovascular risk factor. A sleep study (polysomnography) diagnoses it.
What is REM sleep?
REM (Rapid Eye Movement) sleep is the dream stage, occurring in the later portion of your sleep cycle. It's critical for emotional processing, creativity, and memory. Adults need about 20–25% of sleep in REM. Alcohol, certain medications, and stress all suppress REM.
