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Columbia football continues hot start with overwhelming win against Amsterdam
The Blue Devils got four touchdown passes and 301 yards through the air from senior quarterback Tyler Connolly in a 42-8 victory over Amsterdam.
The 44th Annual Spanish River XC Invitational, best photos
One of South Florida's best cross country traditions continued Saturday with the 44th Annual Spanish River XC Invitational in Boca Raton.
TCU Gets Positive, Negative Injury Updates Before Arkansas State
TCU is set to face off with Arkansas State on Saturday night and the Horned Frogs are ready to welcome back one of their biggest threats. Meanwhile, an offensive powerhouse will wait at least another week to suit up for the team.
Paige Bueckers, Wings handle business vs. Mercury to mark end of an era at College Park Center
ARLINGTON, Texas — The Dallas Wings have two more regular-season games remaining and a playoff run ahead, but Saturday afternoon at College Park Center marked the end of an era.
Caglianone returns to lineup, apologizes for punching wall
Jac Caglianone returned to the lineup Saturday against the Pirates after missing Friday night’s game for punching a dugout wall and cutting his hand. Caglianone addressed the media Saturday before the game, calling it a “very selfish and immature move on my part.” “These guys hold me to a higher standard,” said Caglianone. “I hold […]
Love Moore Loudly brings suicide prevention awareness, hopes to build mental health walking trail
TEXARKANA, Texas --Pickleball players united on Saturday for Hit Hard, Love Louder.at the Southwest Center to play and to support the Love Moore Loudly Foundation.
St. Louis Cardinals vs Washington Nationals Game Discussion Saturday Night
Only two more games for the Cardinals season at Busch Stadium. Saturday night, it’s game 2 of the weekend homestand vs the Washington Nationals. Michael McGreevy is the starter for the Cardinals while it’s LHP Andrew Alvarez for the Nationals. First pitch is scheduled for 6:15pm and the game broadcast will be available through Cardinals.tv.
Nonprofit transforms bookstore into charity closet to raise money for mental health awareness
Seven Stories Bookstore in Shawnee was transformed into a charity closet for the day Saturday, with customers shopping racks of donated clothing to raise money for mental health awareness.
Davante Adams logs full practice Saturday
Los Angeles Rams WR Davante Adams ready to go for the Week 2 contest against the Saints
WATCH LIVE: Pete Buttigieg keynotes Texas Democrats Johnson-Jordan Dinner
Former Transportation Secretary Pete Buttigieg delivers the keynote address at the Texas Democratic Party’s 12th Annual Johnson-Jordan Dinner as Democrats rally ahead of midterms.
Health officials warn of recent measles exposure at PHL Airport
A person with measles traveled through PHL Airport this week, the Philadelphia Department of Public Health announced on Saturday.
Guardant Health (GH) Will Present 20 Abstracts At WCLC 2026
Guardant Health (NasdaqGS:GH) plans to present 20 abstracts at the World Conference on Lung Cancer 2026. The research covers liquid biopsy, methylation based detection methods, AI driven analysis and real world clinical data in lung cancer. Several abstracts focus on machine learning models aimed at assessing metastasis risk and refining diagnostic workflows for clinicians. Guardant Health's WCLC 2026 abstract slate signals broader research momentum that our work places in a wider context...
Saturday Sports: Football, soccer, and swimming updates from around the North Country
Here’s a recap of your North Country sports this Saturday.
National nurses union hosts rally in Bangor against federal healthcare cuts
Maine organizations representing nurses met with the largest registered nurses union in the nation to push back against federal healthcare cuts in Bangor on Saturday.
Yankees' Arron Judge Comments On Injury Timeline
The New York Yankees placed Aaron Judge on the 10-day injured list with a calf strain on Saturday
SEED STEM Festival brings science to life for local children
From building robots to exploring neuroscience, local children got hands-on experience with science, technology, engineering and math Saturday at Aiken’s 41st annual SEED STEM Festival.
Topeka businesses go head-to-head in truck pull to support local pantry
Be Filled of South Topeka hosted its Annual Pull Event Saturday morning.
Toronto Blue Jays Playoff Chances Dealt Blow Early on Saturday
The Blue Jays lost 0.5 games in the standings before even taking the field on Saturday.
Chile's Bachelet quits race to be next UN chief
Michelle Bachelet, the former president of Chile, withdrew her candidacy for the position of United Nations secretary-general on Saturday, weeks after a straw poll showed her in second to last
Spain star drops out of squad for Nations League fixtures
Luis de la Fuente and the Spanish national team coaching staff have on Saturday been dealt a setback on the personnel front. This comes amid confirmation of Pedro Porro dropping out of La Roja’s lat...
Mirassol spoils Tite and Ziyech's Botafogo debuts
It was not a happy debut for Tite in charge of Botafogo.The coach of the Brazilian national team at the 2018 and 2022 World Cups saw Mirassol get the better of his Glorioso this Saturday (20).With the...
Nurses sound alarm on proposed healthcare cuts during Bangor bus tour stop
On Saturday, National Nurses United (NNU) made a stop at Bangor’s Cascade Park as they travel the country on its “Red Alert” bus tour, joined by the Maine State Nurses Association (MSNA).
Saturday Night Open Thread: Can’t Stand *Pats
Come and join this merry band of Steelers’ faithful for some lively debate about our Steelers, good food, music, and the merits of the odd cold beverage.
Photos: Cincinnati Bearcats host Miami RedHawks at TQL Stadium
Cincinnati Bearcats host Miami RedHawks at TQL Stadium in Cincinnati on Saturday, September 19, 2026.
Recap: Boston College scrapes by Maine, 22-16
On Saturday afternoon, the Boston College football team faced off against the Maine Black Bears at Alumni Stadium for Week 3 of the 2026 regular season. The first possession already showed some fireworks when Boston College recovered a Maine fumble on the opening kickoff. But BC failed on their 4th down conversion in the first […]
Snooki announces that she is cancer-free
‘Jersey Shore’ star Nicole ‘Snooki’ Polizzi announced that she is cancer-free after previously sharing her stage 1 cervical cancer diagnosis.
Arkansas volleyball drops final nonconference match before SEC play
The Arkansas volleyball team saw its five-match win streak end Saturday, losing to Illinois in straight sets in the Arkansas State Invitational in Jonesboro.
Auburn opens SEC play vs Florida: Live updates, score, highlights
Follow along for the latest score updates and highlights from Auburn football's SEC opener vs the Florida Gators from Jordan-Hare Stadium.
Brazil's new 9️⃣? Raphinha bags another hat-trick for Barcelona
It’s not “old” news.Raphinha bagged ANOTHER hat-trick in a Barcelona shirt.This time, the feat came this Saturday (19).He scored ALL of Barça’s goals in the 3-1 win over Sevilla right at the ...
Volunteers help Carson City locals receive health checkups at first Love Heals Free Clinic
Locals unable to afford health checkups can get them done by medical professionals today, Saturday, at the Carson City Community Center during the first Love Heals Free Clinic event happening […]
Flora’s all-around day leads Iowa State over Bowling Green
For the first time in school history, Iowa State returned a kickoff and a punt for a touchdown. Jaylen Raynor threw for 133 yards and one touchdown to true freshman Jamal Polite Jr. and Iowa State defeated Bowling Green 55-7 on Saturday. Cam Pettaway, a Bowling Green transfer, had three receptions for 47 yards and […]
Georgia Rolls Past Arkansas in Dominant SEC Opener
No. 2 Georgia wasted no time showing that it is ready for another run through the SEC. The Bulldogs traveled to Fayetteville on Saturday and dominated Arkansas from the opening whistle, cruising to a 45-17 victory in their first conference game of the season. Georgia improved to 3-0 overall and 1-0 in SEC play with…
Barcelona star limps off with injury vs Sevilla
La Liga champions Barcelona have on Saturday been dealt a potential setback on the personnel front. This comes after Andreas Christensen was forced into an early departure from the club’s latest out...
Olid's Man Utd take big step forward after 'intense week'
A week ago, the picture at Manchester United looked bleak. Then on Saturday, victory was snatched away from them at Arsenal. But have we seen signs of improvement from Eva Olid's side?
What We Learned in Gophers’ Blowout Over Akron
The Minnesota Gophers knocked off the Akron Zips on a dreary Saturday in Dinkytown... but there's a lot to fix entering B1G play.
Carrot Top is ‘recovering’ after being hospitalized in Las Vegas, rep says
Carrot Top was hospitalized in Las Vegas on Friday and was ‘recovering’ on Saturday. His scheduled shows at the Luxor over the weekend were cancelled.
Afternoon/Evening College Football Live Thread
We’ll be along shortly with a recap of Georgia’s 45–10 win over Arkansas. But there’s still plenty of college football action on the docket for this Saturday. This will be the forum for all discussion, whether it involves Lane Kiffin or not. The full television schedule for the remainder of the day is here, and […]
Saturday afternoon Orioles game thread: vs. Brewers, 4:05
Where the Birds keep coming close to mathematical elimination from the playoffs, and Félix Bautista is reinstated.
BSD YouTube Postgame Show: Penn State Blasts Buffalo
Penn State takes care of business against Buffalo in their final tune-up before Big Ten play begins next Saturday against Wisconsin. Tim, Jared, and Bennett will be going live around 3:20 PM EST to break it all down for you.
Fiery hat-trick! Salah's masterclass against Galatasaray 🤩🔥
XXL performance from the Little Pharaoh!This Saturday evening, Mohamed Salah was playing his first big clash in Turkey, and he truly rose to the occasion.For the showdown against Galatasaray, the Egyp...
📋 Mirassol and Botafogo named at the Maião, eyeing safety!
There is only one focus for Mirassol vs. Botafogo this Saturday (19): moving away from the relegation zone.The ball gets rolling at 5 p.m. (Brasília time) for the Matchday 28 clash in the Brasileirã...
Health officials warn of possible measles exposure at Union Station
People who were at Union Station between 8 a.m. and noon Saturday are advised to monitor for symptoms through Oct. 3
Krösche and Hütter concede Freiburg outperformed Frankfurt
Eintracht Frankfurt ended SC Freiburg’s perfect start of the campaign with a 2-2 draw at Deutsche Bank Park on Saturday afternoon. However, Markus Krösche and Adi Hütter conceded that the hosts we...
Ed Sheeran's PA Concert Undergoes Major Change Amid Macklemore Controversy
Ed Sheeran's Saturday, September 19, Loop Tour concert in Philadelphia will feature a major change as the singer continues to face backlash.
Yankees Send Aaron Judge Back to the Injured List
The New York Yankees will once again be without their captain and reigning American League MVP, Aaron Judge. The team announced on Saturday morning that the 34-year-old will hit the 10-day injured list (retroactive to September 17th) due to a right calf strain. Judge only appeared in seven games after returning from a fractured rib …
Fiesta de Salud brings free health resources, culture, community to Austin
Families gathered at the Emma S. Barrientos Mexican American Cultural Center on Saturday for Fiesta de Salud, a free community health fair aimed at helping Central Texans start the school year heal…
Fiesta de Salud brings free health resources, culture, community to Austin
Families gathered at the Emma S. Barrientos Mexican American Cultural Center on Saturday for Fiesta de Salud, a free community health fair aimed at helping Central Texans start the school year healthy...
📋 Atlético-MG reveal line-up for clash with Chapecoense
Atlético-MG are lined up to face Chapecoense in the opening match of the 28th round of the Brasileirão. Kickoff is at 4 p.m. this Saturday (19) at Arena MRV.Premiere will broadcast the match. And yo...
Serie A: Roma and Inter Milan in a crazy draw!
A crazy top-of-the-table clash!On Saturday night, the showdown between AS Roma and Inter Milan gave us a completely wild 2-2 draw.Perfectly set on their way by a goal from Manu Koné in the sixth minu...
Trump vows to create ‘AI Force’ and appoint czar amid calls to regulate technology’s development
President Donald Trump said Saturday he plans to create an “AI Force” and name an AI czar as the government faces growing calls to impose guardrails on the rapid development of artificial intelligence.
Lowly Peterborough sack manager Williams
Peterborough United sack manager Luke Williams after Saturday's defeat at home by Doncaster leaves them second from bottom in League One.
Gamethread: Boston College Football vs Maine
The Boston College football team won their first game of the 2026 season last week in a messy game against Rutgers that included seven total turnovers. BC will look to get back to basics against Maine on Saturday, an FCS opponent that they are expected to defeat easily. Who: Boston College Eagles (1-1) vs Maine […]
Arsenal taught ‘big lesson’ by rampant Brighton
Arsenal boss Mikel Arteta said that his side were taught a “big lesson” by Brighton and Hove Albion on Saturday. The Seagulls obliterated the Gunners’ perfect start to the Premier League campaig...
SEED STEM Festival brings science to life for local children
From building robots to exploring neuroscience, local children got hands-on experience with science, technology, engineering and math Saturday at Aiken’s 41st annual SEED STEM Festival.
Congo begins Ebola vaccinations for health workers in the epicenter of the outbreak
BUNIA, Congo (AP) — Congo on Saturday began vaccinating healthcare staff against Ebola in Bunia, the epicenter of the fastest-growing outbreak of the disease in history as they are “particularly
Aaron Donald can solidify himself as the best (again)
Aaron Donald is coming (so they say), and more news on a Saturday!
Heidelberg vs Mount Union college football live updates, highlights
Heidelberg and Mount Union kicked off Ohio Athletic Conference play in college football action Saturday. Click here for live scoring and updates
Michigan Expected to Host Top-100 Quarterback for UTEP Game
Michigan is expected to host Top-100 2028 quarterback Carter Zingelmann during Saturday's matchup against UTEP.
Inside Vanderbilt football vs NC State, Jared Curtis' first start
Here are our best Vanderbilt football vs NC State photos from Saturday, Sept. 19.
🚨 Arsenal thrashed at Brighton!
One of the worst defeats of the Mikel Arteta era took place this Saturday.Arsenal were torn apart by Brighton (Premier League Matchday 5). Final score: 3-0 to the Seagulls against an unrecognizable Gu...
TST Best Bets: September 19, 2026
Lane Kiffin’s return to Oxford was always going to be loud. After leaving Ole Miss for LSU last season, he’ll walk back into Vaught-Hemingway Stadium on Saturday as the coach of one of the Rebels’ biggest rivals. With both teams ranked in the top 10, there’s plenty at stake beyond the reception Kiffin gets.Earlier in the day, No. 16 SMU visits No. 23 Louisville in a ranked ACC matchup. The Mustangs have opened 2-0, while the Cardinals have a chance to make an early statement at home after a 1-1
CNN, MS NOW, Politico reporters denied access to White House following Trump ban
Three reporters were blocked from the White House grounds Saturday morning, a day after President Trump said CNN, Politico, and MS NOW would be banned for reporting "FICTION and LIES."
Guardians News: When Detroit Wins, Cleveland Wins
News and Notes for Saturday, September 19th, 2026
Political cartoons for September 19
Saturday's political cartoons include blaming Biden, the center of attraction, and more
Apple Watch Ultra 4 Sees First Discount After Launch, Now $779.99 on Amazon
The new Apple Watch Ultra 4 just launched yesterday, and Amazon is offering the first cash discounts on select models for the first time since their launch. You can get the Apple Watch Ultra 4 in Natural with Translucent Gray Ocean Band for $779.99, down from $799.00. Note: MacRumors is an affiliate partner with some of these vendors. When you click a link and make a purchase, we may receive a small payment, which helps us keep the site running.
Harvey Barnes makes Newcastle history with quickfire assists ⚡️
Newcastle have jumped out to a lightning-fast start against Hull City on Saturday, taking a 2-0 lead inside seven minutes.And while he isn't on the scoresheet, you have to give credit to Newcastle win...
‘Today’s Gonna Be Wild,’ ‘Love This Sport’ — CFB Fans React As Lane Kiffin Faces Wrath of Ole Miss Fans During ESPN’s GameDay Segment
The rivalry between Lane Kiffin and Ole Miss reached another level Saturday morning when ESPN’s College GameDay went live from Oxford. Within seconds of the broadcast beginning, Ole Miss fans in The Grove broke into loud chants aimed at their former head coach.
Week 3: Saturday College Football Schedule and Open Thread
For all the other games today.
Saturday football open thread
Tottenham may have already played, but there’s plenty of football yet to play today. This is your open thread for that match. Post away. Saturday Match Schedule Brighton vs. Arsenal10 am ET / 3 pm BSTTV: USA Network (USA), not televised (UK)Stream: nbcsports.com Everton vs. Ipswich10 am ET / 3 pm BSTTV: NBCSN (USA), not […]
The Big Holes in Wearable Heart Rate Variability And Readiness Scores
On September 9th, Apple announced it was revamping its Apple Watch Health Sensing System, rolling out a Readiness score (0 to 10), and increasing the frequency of heart rate variability (HRV) outputs 24-fold. This can be viewed as upping its competition with various other consumer wearable sensors. These “readiness scores” as a composite of multiple metrics, with heart rate variability (HRV) being front and center for most. The majority of Americans are now using wearable sensors, which equates to well over 100 million adults. HRV and Readiness scores are increasingly being marketed as a measurement of autonomic nervous system health, a digital marker for future disease, a clock for biological age, and a holistic metric to promote healthspan and even longevity. (Apple also introduced a new longevity tab and “Health Age”.) None of this has been proven. In this edition of Ground Truths I am going to review what we know about heart rate variability and readiness scores. Heart Rate Variability HRV is the variation in normal heart cycle timing. The variability of the heart rate, the barely perceptible millisecond changes in time between consecutive heart beats (see R-R intervals in the Figure below, left panel), is due to interplay between the sympathetic and parasympathetic (vagal nerve) inputs. Distinct from heart rate, individuals with the same heart rate can have very different HRVs. It is a rough reflection of the autonomic nervous system (ANS) activity, inadequate to say whether a person’s ANS function is abnormal. For more than three decades, heart rate variability (HRV) has been measured and several studies have found an association of low HRV and clinical outcomes, particularly a link with higher all-cause and cardiovascular mortality. There have also been less well established links of low HRV to risk of early cognitive impairment, dementia, mental illness, Type 2 diabetes and substance abuse. An important reminder is that HRV is a surrogate marker without any established cause-and-effect relationship. If you increase your HRV, that doesn’t mean it will improve health outcomes. In fact, there is no hard evidence for that. All that work linking to health outcomes was done with electrocardiogram (ECG) derived HRV. Now, in the era of consumer wearables, this is getting assessed differently, by optical pulse (yes, the lights you see) plethysmography (PPG) or what is called pulse rate variability (PRV). They are not the same, as shown below (right panel) and only concordant when the delay between the ECG and pulse is kept constant, which basically means at rest. I should mention there’s also what I will call MPV, a mattress mechanical movement sensor, a derived heart rate variability, that companies like Eight Sleep use, even further away from directly measuring HRV. HRV has not one uniform measurement but many different types of quantification, such as RMSSD, the magnitude of difference between successive R-R intervals of normal sinus beats (N-N) or SDNN, the standard deviation of NN intervals, both in milliseconds. SDNN is one of the so-called frequency domain HRVs (others are LF, HF, LF/HF). Different wearable sensors use different metics; Apple has relied on SDNN and nearly all of the others use RMSSD, which is generally considered the more accurate metric. There’s also the different length of time measured, such as for a matter of minutes, all day, or an overnight’s sleep. Short measurements are especially problematic since they don’t capture enough of respiratory modulation and other factors that influence HRV. Share Ground Truths How well does HRV correlate with PRV? There are very limited studies, especially independently done. One that is commonly cited was conducted by Air Force researchers in only 13 healthy adults assessing Oura ring 3 and 4, Whoop 4.0, and Garmin Fenix 6 and showed a correlation coefficient of 0.88 to 0.97 and a mean absolute percentage error from 6 to 10%. The correlation is not a perfect 1.0, but there’s at least a fairly high level of correlation. HRV is supposed to increase during the night due to takeover of the parasympathetic nervous system, and higher during deep sleep. A recent example of my 1 week, all day “HRV,” and one during sleep is shown below. As you can see, the N of 1 data are inconsistent for the same days from different sensors (Oura, AppleWatch, Fitbit Air, and Eight Sleep) by patterns, absolute numbers, and comparison with prior days and weeks. The largest study in over 8 million Fitbit users (the old version, not Google Fitbit Air, introduced in May 2026) gives you a sense of the effect of age, sex, and the 2 different main HRV (here PRV) metrics, with RMSSD on the left and SDRR (=SDNN) on the right below. That study, from data collected in 2018, is a major outlier, since all the more recent ones are tiny with respect to sample size. Many of the companies have not had independent evaluation of their HRV, such as Eight Sleep, but have published a low standard error on their website. There are some other published studies on the correlation between HRV and PRV, but they are all small and only in healthy adults. A scoping review emphasized the lack of study in underrepresented individuals, including the aged, people of color (which affects the PPG signal), and individuals who are underweight or obese. Add the typical adult age 60 plus with one or more chronic diseases. For example, one study in over 900 adults found poor correlation of HRV and PRV, non-uniformly underestimated across many chronic diseases (cardiovascular, endocrine, neurological, respiratory, and others), concluding PRV is “an invalid surrogate for HRV.” A recent systematic review of 43 studies comparing HRV and PRV found reasonable pooled absolute standardized error (HRV as gold standard) but only 10 of the studies provided quantitative synthesis in ideal conditions. Their main conclusion was similarly cautious: “PPG-derived HRV [PRV] should not be regarded as universally interchangeable with ECG-derived HRV across all devices, populations, and recording contexts.” Factors Affecting HRV and PRV That gets me to the long list of factors that affect HRV (and PRV) besides the device, the type of measurement (RMSSD, SDNN or others), the person’s signal, the sensor site, the duration of data capture, if weighting by sleep stage is used, how artifact is processed and corrected. And this list is not complete!: Oura puts out data from their community of users (who input data) on what affects their overnight HRV. The factors currently provided are: no alcohol (increase 8%), melatonin (increase 2%, float tank (increase 2%), wine (decrease 4%), and party (decrease 14%) in overnight HRV. Must be some big parties! Subscribe What is a PRV measurement good for? It has been falsely characterized as an index of “autonomic balance” and a specific indicator of stress. A 2018 review of the studies available for HRV and its relationship to stress, not using any of the current wearables, found that stress can lower HRV. But so can many other factors. The non-specificity of the signal, indexed to the table above, is striking. Evidence from a UK Biobank study of over 46,000 participants with actual HRV looked at genetically predicted HRV, a genetic risk score, that failed to show the expected HRV-mortality link, indicating that _HRV is likely not causa_l, but rather a reflection of person’s physiologic state. A review of consumer wearable HRV data from 5 longitudinal studies showed that nighttime PRV was not associated with perceived stress, and surprisingly higher HRV, in the largest cohort (N=717 participants), was correlated with higher stress. An Oura ring cohort of 525 first-year college students found a link between overnight PRV and perceived stress, but that was also seen with resting heart rate, sleep, and respiratory rate. Several very small studies have examined the relationship of HRV and athletic injuries or guiding training with mixed, and predominantly negative results. HRV biofeedback training with paced breathing had no significant effect on reducing stress or raising HRV, as demonstrated with sham controlled trials. When HRV for multiple days showed a decline in conjunction with body temperature, the Oura ring published data for prediction of Covid. The WHOOP company sponsored an observational study, published in 2026, of 30,000 users for 72 weeks, without a control group, that reported reduced alcohol intake (5.8 % points) by self-report. That doesn’t tell us much, and particularly about the merits of HRV for behavioral change. If you use the same device and conditions as longitudinal trends for multiple (at least 2-3) weeks that may be the one way to get something useful from the measurements. Data for overnight sleep with minimal motion and using RMSSD is the best proxy for real HRV. The reason to look at trends rather than any given night is that it more likely represents something, even though you won’t know with certainty what the “it” is. Keep in mind there are no data, no peer-reviewed evidence, to show that HRV fluctuation in-person has any correlation with health outcomes. Share Readiness Scores These are proprietary scores that integrate different metrics for each of the wearables: no algorithms have been disclosed. They are unvalidated against health outcomes. In a review of 14 composite health scores of readiness and recovery, HRV contributed 86% to the scores, followed by reading heart rate (79%), physical activity and sleep duration (both at 71%). That review noted the substantial variability in measurement protools and lack of standardization. Sleep staging is notoriously inconsistent and inaccurate by these sensors, which adds further to the HRV uncertainties for what the scores, which use sleep stage data, mean. Only resting heart rate has been shown consistently across devices to be extremely accurate. I’ve made a Table to summarize what we know about which metrics are included, the scores, any peer-reviewed studies that compared the readiness score with health outcomes, and the corresponding (if any, NA-not available) citation. You will note that some companies do not use the term “readiness," such as WHOOP for recovery, and Garmin, which has 2 different scores, one of which is Body Battery. Eight Sleep uses the term “Fitness Score.” They all include HRV; Apple includes a new metric they call “Recovery HRV” which among other components uses 7-days of sleep, but it is unclear what this means or how it is differentiated from other scores (there are clearly no data for outcomes). We have no knowledge of how the different components are weighted or whether any of these scores are better than resting heart rate, HRV alone, physical activity, or any other single metric. Since none of these are standardized, they are not interchangeable, so if you get a 90 for Oura that has no relationship to a 90 on a Google Fitbit Air. Notably, the company can update its algorithm for readiness score at any point without notification to device users. Without any useful evidence of actionability for these scores or established relationship with health outcomes, it is hard to make a case for their value. At the Apple recent announcement they showed their Readiness score (0-10) on the watch (Figure below) but there are no published data on this score, not even on their website. It’s available only on their new Watch Series 12 or Ultra 4 [of course, ;-)]. That exemplifies the problems with these scores, lack of data and evidence for being meaningful to promote health. Perhaps the best study (which isn’t saying much) is the WHOOP Recovery for golfer performance, because it did correlate with an objective outcome, even though there was no control group and the authors were all from the company. Among the 389 pro golfers, an absolute 10-per cent point increase in Recovery score was associated with about 0.5 fewer strokes per round. But that’s hardly a health outcome! WHOOP is also conducting a study in over 2,700 runners to see if their recovery score will be linked to less injuries and improved performance, but that is not yet published and has no control group or randomization. Putting This in Context For two decades I’ve been enthusiastic about the potential for digital health and particularly wearable biosensors. Over the years, we’ve seen some great progress for their ability to promote physical activity and accurately detect atrial fibrillation (the first FDA cleared deep learning AI for consumers). That work was the subject of rigorous research. But there are holes in the data and evidence for other metrics. One notable one is the “VO2 max” story that I wrote about earlier this year. At that time many subscribers asked me to cover heart rate variability, which I finally got to here. When I dived into the research and publication for HRV and readiness scores, I expected to find at least some that were of high quality and demonstrated their utility by linkage to health outcomes. To my surprise, I found none. The wearable sensor measurements for HRV (PRV) are, for the most part, accurate, but that validation work has only been done in small studies of healthy adults and does not take into account the long list of factors, from the device, software side, and the user side, that affect HRV measurements. Moreover, this metric chiefly relies on optical sensing and, as we have learned for heart rate PPG sensing, may be less accurate in people of color. Keep in mind that all of the health outcome association evidence comes from ECG-derived HRV; none are from wearable sensor data. I will repeat the key point: there's no peer-reviewed evidence to show that in-person HRV fluctuation—or efforts to raise your HRV— has any correlation with health outcomes. For those of you who look at your HRV on awakening, or even 2+ week trends of it being low, I hope this context helps to relieve any anxiety. Yes, low HRV (not PRV) has been shown to increase risk of some diseases as summarized above. But efforts to raise your HRV—a surrogate metric— has not been established for improving any health outcomes. HRV does not have any evidence of causality (the genetic evidence actually goes against this possibility). In this summary, I have not included data for other wearable sensors such as Polar, Samsung, Withings, Suunto, Amazfit, Coros, Ultrahuman, or additional mattress sensors. These are beyond my first-hand experience, and as far as I know from my in-depth review none have any peer-reviewed published data that differ from the 6 sensors I’ve reviewed here. From the points I’ve gone over above, we’re not ready for readiness scores. Besides being proprietary, they are predominantly based on metrics that have their own issues. It’s compounding the problem, like building a house without a solid foundation that has never undergone a rigorous inspection, and then selling it. Like I mentioned for PRV, you can look at trends over weeks rather than any single day, to get a handle, but even that may not be helpful. There’s simply no evidence that these scores meaningfully relate to health outcomes. I’d emphasize they might, but that requires doing prospective or randomized studies to prove it. None exist. There’s great promise for HRV/PRV utility_. For example**,**_ Prof Maiken Nedergaard, who discovered the brain glymphatics that are essential in eliminating metabolic waste products from the brain during sleep, has posited that HRV could be a non-invasive marker for neuromodulator oscillations, brain-body regulatory circuits, and brain clearance. That would be extremely useful, but like everything else on HRV and readiness scores it requires solid research and validation. The lay media isn’t helping much to get the story straight. Earlier this year The Economist published a piece entitled “The most useful indicator of your overall health” which ordained HRV as an “accumulated stress score.” That’s akin to the false assertion about VO2max: “V02 max is the singular most powerful marker for longevity.” As I’ve summarized here, that is not established. The fact is that so many things can lower HRV, including physical exercise (especially an intense workout), reduced sleep quality, stress, the list above, no less the device, signal, and software. Whatever fluctuations observed have not been correlated with any health outcome. Sadly, “datamaxxers” are widely using HRV and readiness scores that have never been validated to mean anything. We already know that for some people using the sensors for sleep metrics, it can induce “orthosomnia,” an obsession to get high sleep quality, with associated high levels of anxiety. In an experiment done by a company to promote sleep quality for its employees, “For those employees who did use the trackers, many reported feeling perfectly rested until their tracker told them they had had a terrible night. Others were told that they had slept like a baby when they had actually been lying awake worrying about the quality of their sleep. “ The same problem can result from preoccupation with HRV or readiness scores, with anxiety that would lead to further reduction in both. It you are using a wearable like >100 million American adults, it’s OK to look at these data, but contextualized with the major caveats reviewed here. If you are one to require evidence that HRV or readiness scores are linked to health outcomes, you may not even want to look. The companies make it hard to turn them off! Let me end with the companies that make and sell wearables. Apple’s doubling down on HRV (24-fold more reporting and heart rate very 5 seconds) and introduction of a Readiness score tells us that consumers have bought into these metrics and they are joining the club. However, all of this is occurring with a backdrop of tens millions of users, claims about the data that are not backed up by adequate evidence, marketing way out in front of whatever limited data exists, and not being transparent about their readiness score algorithms. The companies can well afford to do the research that is needed to connect these metrics with health outcomes show, once and for all, that increasing HRV or using readiness scores promotes our health. If they believed and invested in the products they are selling, we’d not be in this position of not knowing. That’s essentially where we are with HRV and readiness scores. Perhaps someday this will change and we’ll have good reason to embrace them. NB: I wrote this post. No AI. I have no conflicts of interest with any of its content. Loading... Ground Truths has 215,000 subscribers from every US state and 214 countries. There are over 300,000 followers of Ground Truths so more than 90,000 folks who can easily convert to be free subscribers. Your subscription to these free essays and podcasts makes my work in putting them together worthwhile. If you’re not a subscriber, please join! If you found this interesting PLEASE share it! Share Ground Truths The proceeds from all voluntary paid subscriptions go to support our summer internship program. It enabled us to accept and support a record number of 62 summer interns that joined us in 2026! These are high school, college and medical students selected from thousands of applicants. We couldn’t do this expanded program without the funds coming in through Ground Truths. Thank you!
Free Museum Day in St. Petersburg: Explore art, science and history
Looking for a low-cost activity in Pinellas County this Saturday? Many of St. Petersburg’s beloved museums are free for one day only.
Northwestern Defense Impresses Colorado Coach Ahead of Saturday Clash
Northwestern football's Tim McGarigle coached defense impressed a Colorado assistant in the film room.
Razorback Report Card: Georgia
The Razorbacks do need to show they can learn from an embarrassing performance. Georgia is not a reasonable measuring stick for a one-week turnaround, but Arkansas must show more than a respectable final score Saturday. The Razorbacks need answers in five specific areas after the 43-10 loss at Utah. Razorback Report Card: Georgia Five Questions …
Coconut Creek 5K raises awareness for suicide prevention, mental health
A walk in honor of suicide prevention and mental health awareness brought people together Saturday morning in Coconut Creek.
Newcastle vs. Hull City
Newcastle United returns to St James’ Park on Saturday to face newly promoted Hull City in the Premier League, looking to respond after Monday’s 4-1 defeat at Leeds United ended its five-game unbeaten start in all competitions. Matthias Jaissle’s side enters the weekend 12th in the table with five points from four league matches and […]
Week 3 HQ: Live college football updates, news, highlights, analysis
Week 3 of the college football season is here, and we'll keep you posted on all the action on Saturday.
Historic German House to host annual Turtle Hill Folk Festival
ROCHESTER, N.Y. (WROC) – The Historic German House in Rochester will be hosting the 55th annual Turtle Hill Folk Festival on Saturday. The gate will open on 315 Gregory Street at 10 a.m. Workshops and...
The Athletic predicts upset in Florida's SEC opener against Auburn
Florida enters Saturday as a road favorite, but The Athletic predicts Auburn will hand the Gators their first loss of the season.
MS NOW says its journalists were denied access to the White House grounds
MS NOW says its journalists were denied access to the White House grounds Saturday morning | WWJ Newsradio 950
MS NOW says its journalists were denied access to the White House grounds
MS NOW says its journalists were denied access to the White House grounds Saturday morning | WBBM Newsradio 780 AM & 105.9 FM
MS NOW says its journalists were denied access to the White House grounds
MS NOW says its journalists were denied access to the White House grounds Saturday morning | KYW Newsradio
MS NOW says its journalists were denied access to the White House grounds
MS NOW says its journalists were denied access to the White House grounds Saturday morning | KNSS Radio
MS NOW says its journalists were denied access to the White House grounds
MS NOW says its journalists were denied access to the White House grounds Saturday morning | KMBZ
Gasperini faces his kryptonite against Inter after 10 consecutive defeats
Roma coach Gian Piero Gasperini faces Inter today, having lost each of his last 10 meetings with the Nerazzurri.Saturday’s game between Roma and Inter at the Stadio Olimpico is arguably the biggest ...
Atlético v Chapecoense: Galo are in action today!
Atlético vs. Chapecoense – September 19 (Saturday) – 4:00 PM🏆 Tournament: Matchday 28 – Brazilian Championship🏟️ Venue: Arena MRV, Belo Horizonte🐓 Pre-match, Commentary, and Post-mat...
Young Newcastle United stars hammer Sunderland
The young Newcastle United stars have hammered Sunderland on Saturday. The United stars of the future having travelled to play at the Academy of Light for an 11am kick-off.
How to Watch SMU vs. Louisville in Massive ACC Showdown
The Mustangs and Cardinals meet Saturday in a ranked matchup that could shape the ACC Championship race and SMU's College Football Playoff resume.
Next stop: New Jersey
The Packers departed Green Bay's Austin Straubel International Airport on Saturday, Sept. 19, 2026, for their Week 2 matchup against the New York Jets.
Saturday Rockpile: Will the real Rockies please stand up?
Colorado Rockies news and links for Saturday, September 19, 2026
Porsche could face another 4,000 job cuts, Handelsblatt reports
Volkswagen's sweeping turnaround plan foresees more than 4,000 further job cuts at Porsche , German business daily Handelsblatt reported on Saturday, following a profit warning linked to problems at the sports car subsidiary.
Mark Kelly Calls for Reversal of Trump’s Healthcare Cuts: 'Making Sure Every American Can Afford Quality Care'
Sen. Mark Kelly (D-Ariz.) called for a reversal of President Donald Trump’s "healthcare cuts," arguing that Americans should be able to access affordable, quality medical care regardless of where they...
Tottenham and Aston Villa kick off Saturday's Premier League action
SATURDAY'S FIXTURES 2026-09-19T10:24:41ZAnd the Villans side aiming to leave London with three points. 2026-09-19T10:24:07ZTottenham's starting line-up for the early kick-off. 2026-09-19T10:21:49ZFi...
Walk this way: Pinellas Republican House campaigns hit the doors on Super Saturday
Republicans outnumber Democrats in Pinellas by almost 50,000 voters.
Arts and entertainment calendar
Events coming up in the Greenville area offer music, arts, theater and family fun. Here is a sampling. “Today” refers to events scheduled for Saturday, Sept. 19.
Sullivan Fall Fest promises family fun
A Fall Festival will take place at the Sorrento Sullivan Recreation Center on Saturday, Oct. 3, from 10 a.m. to 4 p.m.
Rock M Pick ‘Em: Week 3
Week 3 of the College Football season is here, with LSU at Ole Miss highlighting the Saturday slate.
What to know about Akron at Minnesota college football game
Check out what is happening with the Akron Zips and Minnestoa Golden Gophers football teams before Saturday's game.
Real Madrid’s final training session before the derby: three absentees
Real Madrid trained in Valdebebas this Saturday in their final preparation session before Atlético de Madrid vs Real Madrid. Real Madrid completed their final training session in Valdebebas before th...