Posts tagged: Sleep

22 posts found

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Man in bed holding phone checking overnight recovery score in morning light

Oura · Sleep · Readiness

Stop Trying to Raise Your Oura HRV Overnight

Your Oura HRV will bounce night to night. Chasing a higher number misses the point. Here is what to watch instead for steadier sleep and recovery.

James Hoffmann

Sep 14, 2026 1 min read

Runner tying shoes on concrete before morning workout, showing commitment to training plan

Oura · Sleep · Strain

Oura Says Rest. Your Plan Says Train. Who Wins?

A low Oura Readiness Score feels like an order to rest. Here is why regular lifters and runners should treat it as one input, not the plan, and how to decide when to train anyway.

James Hoffmann

Sep 13, 2026 1 min read

Bedside lamp glowing beside an unmade bed at night, showing the quiet bedroom context where alerts would interrupt sleep

Stress · Sleep · Privacy

Why I Told North to Stay Quiet at Night Even When Strain Spikes

Nighttime heart rate spikes look urgent but rarely mean anything actionable at 2 a.m. This memo explains why I chose to keep North quiet overnight and deliver Strain context in the morning instead.

James Hoffmann

Sep 13, 2026 1 min read

Morning sunlight through blinds falling across an unmade bed, showing the moment a low sleep score lands

Sleep · Rune 1 · How It Works

Why I Cut the Morning Score That Made People Feel Behind

During Rune 1 testing I kept skipping workouts after a red morning grade. Here is why I removed that single judgment score and what we kept instead for our Q3 2026 pre-launch.

James Hoffmann

Sep 13, 2026 1 min read

A person sleeping on their side with a smart ring on their finger, illustrating how body position compresses the finger against a pillow or mattress

Sleep · Wearables

Why Your Smart Ring's Nighttime Data Is a Lie: The Sleep Position Problem Nobody Mentions

Your smart ring's PPG sensor assumes your finger is at heart level with unrestricted blood flow. When you sleep on your side, neither of those things is true. Here is what the data actually looks like.

James Hoffmann

Jun 21, 2026 1 min read

A pregnant woman wearing a smart ring, with abstract biometric data lines flowing around her finger

Sleep · On Device Ai · Wearables

Your Smart Ring Has No Idea You're Pregnant: How Pregnancy Breaks Every Biometric Algorithm

Pregnancy raises your resting heart rate by 10 to 20 bpm, drops your HRV, raises your temperature, and changes your sleep architecture. Every wearable algorithm trained on non-pregnant baselines gets this wrong. Here is what the data actually looks like.

James Hoffmann

Jun 21, 2026 1 min read

An assortment of prescription medication pills scattered across a surface, representing the medications that alter biometric signals measured by smart rings

Sleep · Wearables · Hrv

The Medications That Break Your Smart Ring's Algorithms

Beta-blockers suppress HRV by 30 to 50 percent. SSRIs alter sleep architecture. Antihistamines fragment deep sleep. If you take medication and your smart ring gives you bad scores, the problem might not be your body.

James Hoffmann

Jun 19, 2026 1 min read

Closeup of roasted coffee beans scattered on a white surface, representing the source of caffeine that disrupts wearable biometric readings

Sleep · Wearables · Recovery

Why Your Morning Coffee Confuses Your Sleep Tracker: Caffeine, Biometrics, and the False Recovery Signal

Caffeine changes your biometrics in ways that look like recovery to a wearable. Higher HRV, elevated resting heart rate, and altered sleep architecture produce a readiness score that says you are rested while your body metabolizes a stimulant. Here is how the blind spot works and what wearables could do about it.

James Hoffmann

Jun 17, 2026 1 min read

A glass of wine and alcoholic drinks on a bar table, representing the common context of drinking before sleep

Sleep · Wearables · Recovery

What Your Smart Ring Misses After a Night of Drinking: Alcohol and the Anatomy of a Broken Biometric

Alcohol breaks your wearable's data in three compounding ways. HRV goes up (which looks like recovery but is the opposite), deep sleep increases from delta wave activity (low quality), and PPG signal quality degrades from dehydration. Your readiness score may look fine while your body is metabolizing a toxin.

James Hoffmann

Jun 17, 2026 1 min read