What your smartwatch and home devices measure: heart rate, blood pressure, HRV, SpO2 and sleep. Normal ranges and what your numbers mean.
A smartwatch AFib alert can be genuinely unnerving: one glance at your wrist, and your watch is suddenly telling you that your heart rhythm may not be normal. Before you panic — or dismiss it — here is the balanced truth from a doctor’s point of view. That alert is worth taking seriously, because the…
Heart rate recovery is one of the most telling numbers your smartwatch quietly records, yet few people know to look at it. It is not about how low your pulse goes, but how quickly it comes back down after you stop exercising. Push your heart rate up on a run or a flight of stairs,…
Wrist temperature has quietly become one of the most talked-about numbers on modern smartwatches and rings, measured while you sleep and then tracked night after night. Yet it is also one of the most misunderstood. It is not the same as taking your temperature with a thermometer, and a single reading tells you almost nothing…
Sleep efficiency is one of the most useful numbers your smartwatch or ring quietly reports each morning — and one of the least understood. It is simply the share of your time in bed that you actually spend asleep, written as a percentage. You can be in bed for eight hours and still have poor…
Pulse pressure is a number hidden in plain sight in every blood pressure reading — the gap between the top and bottom figures. A reading of 120/80 has a pulse pressure of 40. It’s rarely mentioned at a check-up, yet it can reveal something the two numbers alone don’t: how stiff or flexible your arteries…
If your watch nags you to hit 10,000 steps a day, here’s some freeing news: that number was never based on science. It came from a 1960s marketing campaign, not a study. So how many steps a day do you really need? Research now points to a more achievable answer — and to the reassuring…
Your respiratory rate — how many breaths you take in a minute — is one of the four classic vital signs, alongside your heart rate, blood pressure, and temperature. It’s also one of the most revealing: breathing often speeds up before anything else when the body is under strain, which makes it an early warning…
A normal body temperature isn’t the single, fixed 37°C (98.6°F) most of us grew up with. That famous figure comes from a study in the 1800s, and modern research puts the true average a little lower — and, more importantly, shows that your temperature is always on the move. It rises and falls through the…
If your fitness watch nudges you about “Zone 2” or splits your workout into coloured heart rate zones, it’s using a simple but powerful idea: the harder you work, the faster your heart beats, and different heart rates train your body in different ways. Heart rate zones turn that relationship into five bands of intensity,…
If your sleep tracker breaks your night into sleep stages — light, deep, and REM — it’s showing you something your body has been doing all along: cycling through distinct phases that each do a different job. Far from being a single “off” switch, sleep is an active, structured process, and understanding these stages explains…