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Sep 1, 2026 Inappropriate Sinus Tachycardia vs POTS: How to Tell Them Apart Both make your heart race, but the tell is timing. Inappropriate sinus tachycardia runs fast even at rest; POTS is normal lying down and surges when you stand. Here is how to read the difference at home without spiraling. POTS Aug 27, 2026 Coat Hanger Pain: Why Your Neck and Shoulders Ache When You Stand Coat hanger pain is the aching band across the back of the neck and shoulders that builds the longer you stay upright and eases when you lie down. Here is why it happens in POTS and orthostatic intolerance, how to tell it apart from ordinary neck tension, and how to track it. POTS Aug 24, 2026 Tilt Table Test: What to Expect and How It Diagnoses POTS and Syncope A tilt table test tips you upright on a motorized table while your heart rate and blood pressure are watched continuously. Here is what actually happens during the test, how it is read, and how it differs from the stand test you can run at home. POTS Aug 21, 2026 Vasovagal Syncope: Why You Faint and How to Stop It Vasovagal syncope is the most common reason people faint: a reflex that briefly drops your blood pressure and heart rate so your brain loses blood flow for a few seconds. Here is what the reflex is doing, how to read the warning signs, and the counter-pressure moves that can stop a faint before it lands. Basics Aug 20, 2026 Respiratory Sinus Arrhythmia: Why Your Heart Rate Rises and Falls With Each Breath Respiratory sinus arrhythmia is the normal, healthy way your heart speeds up as you breathe in and slows as you breathe out. It is the single biggest source of your beat-to-beat HRV, and understanding it explains why slow breathing raises your numbers. HRV Aug 18, 2026 Orthostatic Hypotension vs POTS: How to Tell Them Apart Both make you dizzy when you stand up, but they are opposite problems on the monitor. Orthostatic hypotension is a blood-pressure drop; POTS is a heart-rate surge with the blood pressure holding. Here is how to read the difference at home without spiraling. POTS Aug 15, 2026 Hypermobility, hEDS and POTS: Why Bendy Joints and a Racing Heart Travel Together Joint hypermobility, hypermobile Ehlers-Danlos syndrome (hEDS) and POTS overlap far more often than chance. Here is the connective-tissue link, what the Beighton score does and does not tell you, and how tracking changes the management. POTS Aug 14, 2026 How Long Should You Measure HRV? Reading Length, Explained How long to measure HRV depends on which metric you care about and how consistent you want your trend to be. Ultra-short 1-minute readings can track vagal tone, but the classic 5-minute reading is the reference standard, and mixing lengths quietly breaks your baseline. Here's how to choose one length and stick to it. HRV Aug 11, 2026 Overnight Heart Rate: What Your Sleeping Low and High Reveal Your overnight low is the cleanest resting heart rate you will ever get: no posture, no caffeine, no white-coat effect. Here is when in the night it happens, what the overnight high reflects, and why a rising low is one of the earliest warnings you have. Basics Aug 10, 2026 Baroreflex Sensitivity: The Reflex That Keeps You Upright The baroreflex is the fast feedback loop that steadies your blood pressure every time you stand, and its sensitivity is one of the clearest measures of how well your autonomic system responds. Here is what baroreflex sensitivity means, why it runs low in POTS and long COVID, and how your HRV and stand test give you a home-usable proxy. Basics Aug 8, 2026 The Poincaré Plot in HRV: What SD1 and SD2 Actually Show The Poincaré plot turns your heartbeat intervals into a scatter of dots, and its two descriptors, SD1 and SD2, summarize the shape. SD1 is your fast, vagal beat-to-beat change; SD2 is your overall variability. Here's how to read the cloud and the numbers. Basics Aug 4, 2026 HRV Baseline: How to Build One and Read Every Reading Against It A single HRV number means almost nothing on its own. Your baseline, your own rolling average and the normal spread around it, is what turns each morning reading into a signal you can actually trust. Here is how to build one and how to read today against it. HRV Aug 3, 2026 Heart Rate Recovery After Exercise: What the Drop Tells You Heart rate recovery is how fast your pulse falls in the first minute after you stop moving. It is one of the clearest windows onto vagal reactivation, the parasympathetic system switching back on. Here is how to measure it, what a good drop looks like, and how to read it if you have POTS or long COVID. Basics Aug 1, 2026 Why Is My HRV Low? Causes of Low Heart Rate Variability A low HRV reading rarely means something is wrong on its own. Here are the everyday causes of low heart rate variability, the condition-related ones, and how to tell a meaningless one-day dip from a trend worth watching. HRV Jul 24, 2026 HRV Normal Range by Age: What Counts as a Good Score? Heart rate variability falls with age and differs by sex, so there is no single 'good' number. Here are the realistic HRV ranges by age, why the bands overlap so heavily, and why your own baseline tells you far more than any chart. HRV Jul 23, 2026 POTS Subtypes Explained: Hyperadrenergic, Neuropathic, and Hypovolemic POTS is usually grouped into three overlapping patterns: neuropathic, hyperadrenergic, and hypovolemic. Here is what each one means, how they differ, and what your at-home stand-test numbers can hint about which pattern is driving your symptoms. POTS Jul 9, 2026 Autonomic BP Indices: Kérdő, Robinson & Kvas From three simple numbers (systolic, diastolic and pulse) you can derive several older physiology indices that read autonomic balance and cardiovascular efficiency. They are research tools, not clinical verdicts, so their value is in your own trend. Here is what each one means and how to read it. Basics Jul 9, 2026 Blood Pressure Basics: Systolic, Diastolic & Pulse The three numbers on a blood-pressure reading each tell a different story: systolic is the peak as your heart contracts, diastolic is the resting pressure between beats, and pulse is how fast it all repeats. Here is what each one means and how a recovery-focused reading differs from the clinical chart. Basics Jul 9, 2026 How to Measure HRV Accurately at Home The secret to at-home HRV isn't an expensive device: it's consistency. Same time, same posture, same length, every day. Here's how to take readings you can actually trust, why the trend matters more than any single morning, and how to stop fooling yourself with noise. Basics Jul 9, 2026 HRV Frequency Domain: VLF, LF, HF & Total Power Explained Your heartbeat rhythm can be split into frequency bands, each reflecting a different piece of autonomic regulation. Here's what HF, LF, VLF and total power actually mean, why the mix matters more than the total, and how to read the LF/HF ratio without over-trusting it. Basics Jul 9, 2026 HRV Histogram Metrics: Mode, AMo50, MxDMn and CV Mode, AMo50, MxDMn and CV are the geometric HRV metrics: four different reads on the shape of your heartbeat-interval histogram. They're the raw ingredients behind the Baevsky stress index. Here's what each one describes and how to grade it. Basics Jul 9, 2026 LF Peak, HF Peak, Coherence & Resonance Breathing Frequency-domain HRV isn't only about how much power sits in each band: it's about where the power concentrates. Here's what the LF and HF peaks mean, why paced breathing pulls them into place, and how resonance-frequency breathing at about six breaths a minute maximizes your HRV. Basics Jul 9, 2026 Mean Arterial Pressure & Pulse Pressure, Explained Systolic over diastolic is only the start. Two derived numbers, mean arterial pressure and pulse pressure, often say more about how well your circulation is actually perfusing your organs, and both are quietly informative in POTS and orthostatic intolerance. Basics Jul 9, 2026 PNS Index, SNS Index & Stress Index: The Balance Trio Three numbers the app shows side by side to describe autonomic balance: the PNS index (your rest-and-recover side), the SNS index (your fight-or-flight side), and the Baevsky stress index. Here's what each one means and how they move together. Basics Jul 9, 2026 Resting Heart Rate & Mean RR: Your Simplest Autonomic Signal Resting heart rate is the plainest read on your autonomic load, and a creeping baseline is often the first sign of a bad stretch. Here's why position changes the number, how mean RR is the same information seen from beat-to-beat space, and how to read a rising resting HR in POTS recovery. Basics Jul 9, 2026 RMSSD and pNN50: Your Two Vagal-Tone Metrics, Explained RMSSD and pNN50 are the two time-domain numbers that track vagal tone, the parasympathetic 'rest and digest' side of your nervous system. RMSSD is the cleanest day-to-day recovery signal you have. Here's what each one means and how to read them. Basics Jul 9, 2026 RR Intervals & the Tachogram: The Raw Data Behind HRV Every HRV number you'll ever see is built from one simple series: the time in milliseconds between your heartbeats. This is the plain-language explainer for RR intervals, the tachogram that plots them, and why a healthy trace looks like rolling waves rather than a flat line. Basics Jul 9, 2026 The Autonomic Score & Grade Bands: One Number, Explained Every colored tint in the app traces back to one system: a 0–100 readiness score and a ladder of grade bands from Excellent down to Crash, plus a violet Warning flag for readings that are suspiciously high. Here's how raw metrics become a single number, and how to read it without over-trusting it. Basics Jul 9, 2026 What Is SDNN in HRV? Your Total Variability, Explained SDNN is the broadest single HRV number: the standard deviation of the gaps between your heartbeats. Here's what it measures, why short readings run lower than the figures you see quoted, and how to read it as a recovery signal. Basics Jul 2, 2026 The Autonomic Nervous System & Dysautonomia: A Complete Guide Your autonomic nervous system runs everything you never think about: heart rate, blood pressure, digestion, temperature. When it stops regulating properly, that's dysautonomia. Here is how it works, what goes wrong, and why it's measurable. Basics May 28, 2026 What HRV Actually Is, And Why It Matters for POTS Recovery Heart rate variability is one of the clearest windows into your autonomic nervous system. Here is what it measures, why it drops in POTS and post-viral illness, and how to read it without obsessing. HRV May 21, 2026 The Orthostatic Stand Test: How to Do It at Home (and What the Numbers Mean) The lying-to-standing heart rate test is the single most useful at-home measurement for POTS. Here is how to run it consistently and how to read the rise and recovery. POTS May 14, 2026 Turn Months of Data Into a Five-Minute Doctor Conversation Appointments are short and symptoms are hard to describe from memory. Here is how to use your own tracked data to walk in with a clear, specific summary your clinician can act on. Recovery May 9, 2026 How POTS Is Diagnosed: The 30-BPM Rule, the Tilt Table & What to Expect POTS is diagnosed by a sustained heart-rate rise on standing without a big blood-pressure drop, symptoms lasting months, and other causes ruled out. Here is what the criteria mean and what the tests feel like. POTS