I'm a tracker sceptic. Would these cutting-edge devices convert me?

Times

04-06-2025

In fitness terms, I am what might be termed an anti-tracker. I ditched most wearable devices a couple of years ago and, aside from my daily steps, I don't monitor my activity or any of the data related to it, including my heart rate, stride length, cadence, breathing efficiency, relative effort and elevation gains. I don't upload my runs or workouts to Strava, Runkeeper or Apple Fitness, so I don't receive likes or 'kudos' — and yet I feel better for it. My body is sufficiently attuned to my state of fitness or fatigue to let me know when I should push or ease off. I don't need a wristband to tell me.
However, when it comes to general health and medical issues, I'll reluctantly concede that I might benefit from more of a regular insight. At 56, I am at the prime age for things to start falling apart and for early signs of age-related decline to set in. As yet I have no problems to report but am surrounded by apparently fit and healthy friends who thought the same until midlife got the better of them and their heart, blood sugar, sleep or joints took a turn for the worse. While it pains me to consider daily tracking, I am prepared to give it a go, albeit in the knowledge that continuous monitoring and feedback from such devices can, ironically, bring its own health issues.
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In the most recent wearable technology report by Mintel, the market research company, a survey of more than 2,000 smart watch owners found that 48 per cent confirmed tracking health data made them more stressed about their health, rising to 57 per cent of people who own smartwatches. Other researchers have blamed sleep trackers for causing 'orthosomnia', defined as the obsessive pursuit of perfect sleep and cited as a reason why sleep might get worse rather than better when wearing one.
I have friends who can't seem to function without a health prompt or update from their phones. The last thing I want is to become one of the worried well. As a sceptic, what would a week of tracking my health teach me, if anything at all? Here's what I discovered:F
Tracker Lingo (from £59 for a two-week starter plan including two sensors; hellolingo.com)
How it works A continuous blood glucose monitor (CGM) is a plastic disc that attaches to the back of your upper arm and measures how much sugar is in the fluid surrounding your cells every few minutes via tiny needle-like sensors that sit beneath the skin. Data is sent to an app on your phone in real-time and you get alerted if your glucose levels are too high, a risk factor for type 2 diabetes, or too low. The idea is that you gain a better understanding of how to maintain stable blood glucose levels that might positively impact your mood, sleep and food cravings. Poor blood glucose management has also been linked to weight gain.
What it told me According to Lingo, a normal blood glucose range is within 3.9-7.9 millimoles per litre, although it simplifies this with a single target called your Lingo Count. Mine was initially pre-set at a standard 60 — my goal being to stay below that — but after a week Lingo adjusted the target to 50. Following a fasted morning run, my count was low (16) and eating my late morning porridge with berries, my morning staple, didn't raise it out of range. A cocktail at the weekend saw it hit 80 temporarily, but generally, as expected, it peaked after meals.
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Verdict I have tried a couple of other CGM devices in the past and found them frustratingly tricky to administer. My first attempts to extract the two Lingo monitors, produced by Abbott, from their containers failed and the tiny needles broke so I had to order more. They are designed to be worn for seven days but, even with adhesive stickers to keep them in place, one of the replacements came off in the shower after 36 hours.
Although the app was easy to download and digest, I found some of the advice irrelevant. On an afternoon when I barely had time to eat I was warned my blood sugar count might be escalating. After a morning run and dog walk followed by breakfast I received an alert to do 5-10 minutes of calf raises to mitigate a blood sugar rise.
I would be reluctant to continue, particularly after research at the University of Bath published in the American Journal of Clinical Nutrition last month suggested there is not much point as CGMs provide misleading results. In their study, researchers measured blood sugar responses in healthy volunteers (non-diabetic and a healthy weight) using either a CGM (in this case Abbott's Freestyle Libre 2) and the gold standard finger-prick test. The CGMs overestimated the time spent above a normal blood sugar level threshold by nearly 400 per cent, potentially causing unnecessary anxiety.
'CGMs are fantastic tools for people with diabetes because even if a measurement isn't perfectly accurate, it's still better than not having a measurement at all,' says Professor Javier Gonzalez, a nutrition and metabolism researcher who led the study. 'However, for someone with good glucose control they can be misleading based on their current performance.'
Relying on CGMs could also lead to unnecessary food restrictions or poor dietary choices, Gonzalez says. In the trial, whole fruit was misclassified as medium or high-GI foods by the CGMs, while a finger-prick test showed they were low-GI with minimal adverse effect on blood sugar. I can see it might become an obsession but I question the purpose — and cost — of doing it long term.
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Tracker Hilo cuff and wristband (£209.99; hilo.com)
How it works Blood pressure is assessed using the Hilo cuff, which is attached to the upper arm via a Velcro strap and inflates to take the average of three separate readings. Continuous daily blood pressure is then calibrated and recorded via the wrist-worn strap with all results downloaded to an accompanying app, which is free for the basic daytime and nighttime monitoring but costs £4.99 per month for added insights, analytics and syncing with the Apple Health app on your iPhone. A monthly recalibration using the cuff is required.
What it told me A blood pressure reading consists of two numbers: the top number is your systolic pressure, the highest level your blood pressure reaches during a heartbeat; the bottom number is your diastolic reading, the lowest level your blood pressure hits between heartbeats. A normal blood pressure range is between 90/60mmHg (millimetres of mercury, a unit of pressure) and 120/80mmHg. For me, the stats were unchanging and within the normal range day and night with a reading of 118/79.
Verdict Advice from the NHS is to get blood pressure tested every five years once you get to 40, and you can get tested for free at a community pharmacy from this age. It is a good idea to check it more frequently once you have had a professional reading, especially if you take HRT or have heart disease in the family (neither for me) in which case you should consult your GP.
Dr Nikhil Ahluwalia, a cardiology registrar at Barts Heart Centre in London, says the Hilo cuff is one of the home devices that is accurate and easy to use, but he doesn't recommend continuous screening. Blood pressure ebbs and flows on a daily basis, he says, and if you don't have existing hypertension, then once or twice a month is probably often enough.
'There's no evidence that continuous monitoring of blood pressure offers benefits unless prescribed by your GP,' Ahluwalia says.
I did love the strap for its simplicity — it's slimline and has no flashing lights or bright screens so you do forget you are wearing it. However, the NHS recommends measuring blood pressure on the upper arm, not the wrist or finger.
Tracker Oura Ring (from £349; ouraring.com)
How it works A ring containing sensors that is worn on your index or middle finger. Connects to an app that provides a daily range of sleep (and other health) stats and an overall 'sleep efficiency' score.
What it told me I am a smug sleeper and have never felt the need to use a tracker to confirm I get enough rest at night or that I might need more after an interrupted night. Results confirmed my status as a sleep queen as I was awarded a crown by the app for 'optimal sleeping' with an efficiency (time asleep versus time awake) score of 89. My total nightly sleep ranged from 7hr 7min (woken by the dog barking at a fox in the garden) and a blissful 7hr 56min over the bank holiday weekend. On average, my sleep latency — the time it takes to drop off — was 12 minutes. My Ring told me I got an average of 1hr 23min each night of deep sleep, the type that leaves you refreshed and alert the next day. It did suggest I fidget a lot — I was advised to 'pay attention' to my restfulness, although I'm not sure how I'd address this when I am sleeping so soundly.
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Verdict I don't like wearing a watch at night and when my partner wears his I swear it lights up the entire room. If I felt the need to monitor my sleep, a ring would be the least invasive means of recording my shut-eye. Results were easy to read and digest — although you can lose yourself if you delve into the endless graphs and charts — and I only needed to recharge it once in seven days. However, studies show that no tracker is a match for gold-standard polysomnography tests that measure brain waves, heart rate, breathing, blood oxygen levels and body movements during sleep through electrodes attached to the skin and scalp. A study by Yale University scientists found sleep trackers to be accurate only 78 per cent of the time, dropping to 38 per cent when it comes to measuring how long it takes people to drop off, so I am taking the results with a pinch of salt.
Tracker Apple Watch (from £219; apple.com)
How it works There are dozens of health-tracking options on the Apple Watch, but I used it to gauge my heart health and set it to alert me to very high or low heart rates. There's also an electrocardiogram (ECG) feature, activated by placing an index finger on the digital crown of the watch for 30 seconds, which records heart rhythm via an electrical sensor and detects irregularities. It can be used to determine your risk of atrial fibrillation (AFib), which occurs when electrical impulses that trigger muscle contractions of the heart misfire chaotically. Left undiagnosed or untreated, AFib raises the risk for stroke and heart failure. Results are logged on the Apple Health app and a pdf of ECG readings can be shared with your GP.
What it told me I don't routinely track my heart rate, but over the years I have been told my resting heart rate (beats per minute or bpm when sitting or lying down) is lower than the average 60-100bpm, which is probably a hangover from hard endurance training in my teens and twenties.
I set the watch to alert me if it dipped below 45bpm but its repeated pinging suggested it wondered if I was alive with my daily average of 39bpm. That got me googling slow heart rates, termed bradycardia, and stressing about whether I needed to see a GP, which the British Heart Foundation suggests might be necessary if it is accompanied by fatigue.
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Am I more tired than normal? That's something even the watch can't tell me, although Ahluwalia says I don't need to worry. 'If your heart rate is suddenly much lower than normal it is a cause for concern,' he says. 'If low is your normal range, then it is OK.' I also did daily ECG readings for the week which confirmed at least I was not in the at-risk range for AFib.
Verdict All heart health data (including cardiovascular fitness, walking heart rate, ECGs and cardio recovery) are neatly stored together in the Health app on an iPhone so it is easy to access. It was encouraging that several studies, including a 2023 paper published in the journal Cureus, and cardiologists I spoke to support Apple Watch technology for monitoring heart health. I can see myself checking it periodically — provided I remember to wear my Apple Watch.