SCROLL NEWS / DISCOVERY
Search headlines
Find the stories shaping the conversation.
Results for " weekly " 2,193 found 🔀 AI-powered Shuffle
Top Weekly Entertainment Picks
The first weekend of fall has arrived and South Jersey is the place to be. Experience the excitement of Margate’s Fall Funfest, hear the soulful sounds of Tom
Oprah Winfrey reveals the biggest ‘mistake’ of her career (exclusive)
Oprah Winfrey reflects on her career in Entertainment Weekly’s exclusive clip from her conversation with LinkedIn Editor in Chief Dan Roth.
“Sopranos” writer and “Age of Disclosure ”director to adapt bombshell memoir from ‘real-life Agent Mulder’
Emmy winner Terence Winter tells EW the series answers “whether we are the only intelligent life in the universe.”
Out & About: A weekly guide to live and local entertainment
Thursday, Sept. 24 Music
The Herald's weekly entertainment picks
Looking to be entertained from Thursday, Sept. 24, through Wednesday, Sept. 30? Check out the Skagit Valley Herald’s weekly recommendations.
Weekly Entertainment Report: Live music and lively arts, Sept. 24-27 » Nashua Ink Link
"Music makes the people come together." - Madonna
Derek Hough addresses backlash over “Dancing With the Stars” judges giving one-word critiques
The dancer-turned-judge responded to fans by quoting Michael Scott from “The Office.”
The 12th Jaipur Literature Festival in Boulder - The Integration of Arts, Science and Culture
Boulder is celebrating diversity with the Jaipur Literature Festival.
Sean Sharaf considering retirement after beating Gable Steveson
Sean Sharaf ponders retirement after Gable Steveson win.
Justin Gaethje is flirting with the thought of retiring
Justin Gaethje is questioning retirement.
Roseanne Barr calls Michael Fishman a ‘little f---ing worm’ for saying “Roseanne” revival was rightfully canceled
The comedian didn’t hold back when sharing her true feelings for Fishman, who played her TV son for 10 seasons.
Hoda Kotb shares surprising way she disciplined her daughter after she ran off on her own
The former “Today” host is mother to Haley, 9, and Hope, 7.
Disney's 'Moana' Remains Atop U.K. Home Entertainment Sales Chart Through Sept. 23
Disney’s live action Moana remained No. 1 on the Official Film Chart, the weekly U.K. home entertainment sales chart, through Sept. 23. Universal’s Disclosure Day, returned to the Top 10 at No. 2, up 22 spots in its ninth week on the chart. At No. 3, Warner’s new release The End of Oak Street. Starring … Continue reading "Disney’s ‘Moana’ Remains Atop U.K. Home Entertainment Sales Chart Through Sept. 23"
Rare country performance set for MTV VMAs as show reveals Dolly Parton tribute led by huge genre star
The MTV VMAs typically don’t feature country music on the main show, though a huge country star will tribute Parton after the icon’s death.
Harry Shum Jr. says it ‘means the world’ to see “iCarly” costar Miranda Cosgrove support him on ‘DWTS’
The season 35 competitor also celebrated the presence of his “Shadowhunters” and “Crazy Rich Asians” costars.
Harvey Weinstein sentenced to 15 years after being convicted of sexually assaulting ex-“Project Runway” staffer
The disgraced producer appeared in court on Sept. 23.
Lili Reinhart explains importance of ‘startling’ sexual harassment scene in “The Love Hypothesis”
The actress tells EW that she and costar Arty Froushan did not “shy away” from bringing the moment to life.
Mark Ballas subtly shuts down conspiracy theories about Whitney Leavitt’s “Traitors” casting
The “DWTS” pro, who was partnered with Leavitt last season, claims she’s been set to head to the Scottish Highlands “for a while.”
“9-1-1’”s Peter Krause reacts to fan theory that Bobby Nash could still be alive
Krause recently stepped into a new role on NBC’s “Line of Fire,” following the shocking death of his beloved firefighter character.
Patriots' Drake Maye Earns Worrying Label on 'Gross' Ranking
With four interceptions to start the year, a weekly ranking believes Drake Maye appears "rattled" this season.
“The Amazing Race” host Phil Keoghan pitches 5 reasons to watch season 39
It includes one of the most personal and emotional days ever on set for the host.
Science, Unleashed
Dogs hear things we miss. Cats spot things we don’t. Turns out, there’s some cool science behind it. This fall, Cox Science Center & Aquarium is giving families a chance to step inside the sensory world of their favorite four-legged companions with “Cats & Dogs,” a large-scale exhibition that blends science, behavior and culture. The
Maura Higgins reveals how she broke Mark Ballas’ tooth in “DWTS” rehearsals
“I’ve taken elbows to the face before, it’s fine,” Ballas said.
Ella Langley says ‘it feels fake’ after shattering Mariah Carey’s record for longest-running No. 1 song in history
“I’m genuinely trying to find the words to help explain what’s going on in my brain,” Langley said as “Choosin’ Texas” broke Carey’s record with 23 weeks on top.
“Survivor 51 ”cast deliver super dramatic exit lines after being blindsided (exclusive)
Who’s got the most epic send-off?
“Rocky IV”’s Dolph Lundgren hints at ups and downs in Sylvester Stallone friendship: ‘Buddies again’
Lundgren broke down their relationship in his “Fights Worth Fighting” memoir.
This week in Santa Cruz County business: Summit on economic opportunities for local arts; Verve workers reach tentative contract; voting underway for Lookout List
A Monterey Bay Economic Partnership summit focused on improving the economic health and quality of life of Santa Cruz, San Benito and Monterey counties, a union deal for local Verve Coffee Roasters employees and how to show your favorite local businesses some love – it's all part of Jessica M. Pasko's weekly column.
“DWTS ”judge Carrie Ann Inaba claps back at audience booing her over Harry Shum Jr. critique
“You can boo as long as you vote!” she told the unhappy crowd.
Dolly Parton’s estate files lawsuit against terminated nephew, claims he made violent threats
Bryan Seaver is accused of “threatening” his late aunt’s estate and “those associated with Miss Parton’s legacy.”
Bucs Nation Reacts Survey: Are you confident, Buccaneers fans?
Welcome to SB Nation Reacts, a survey of fans across the NFL. Throughout the year we ask questions of the most plugged-in Buccaneers fans and fans across the country. Sign up here to participate in the weekly emailed surveys:
CS2 Chicken Egg Drops Spotted by Players on Reddit
CS2 players report receiving a mysterious Chicken Egg item in weekly drops, sparking speculation about upcoming in-game pets.
Auburn Weekly Roundtable
Week 4 has arrived, and the Auburn Tigers are looking for a bounceback after their 42-39 loss to the Florida Gators. It’s Homecoming on the Plains, and the Vanderbilt Commodores are in town, who have had the Tigers’ number over the past few seasons.
Turf Show Times Reacts Survey
Welcome to SB Nation Reacts, a survey of fans across the NFL. Throughout the year we ask questions of the most plugged-in Rams fans and fans across the country. Sign up here to participate in the weekly emailed surveys:
Howard Schultz joins Ryan Clark as investor in The Pivot
Ryan Clark may have suffered a tough blow when he was laid off from ESPN earlier this year, but he is moving forward on his own in a major way. After a partnership with NFL Films launched a new weekly sports show through his production company, The Pivot, Clark has even bigger news. Pivot25 Productions…
Bears-Vikings stock watch: Bradbury down, Muhammad up
The Bears laid a massive egg with plenty to improve. @SamHouseholder has his weekly stock watch
David Spade wants to ask Drew Barrymore if they’ve ever made out: ‘I don’t know if we did’
Now this sounds like a question for Drew’s News!
Why Greg Evigan passed on “Knight Rider” lead: ‘I didn’t want to do the same thing again’
The actor went on to flex his comedy chops when he starred on “My Two Dads,” with Paul Reiser.
Country star overthrows Mariah Carey’s record for longest-running No. 1 song in U.S. history
Carey previously held the title with her perennial Christmas smash “All I Want for Christmas Is You,” though a rising country act has now shattered the record.
Billy Bush returns to network TV with new gig 10 years after Donald Trump scandal
Bush will serve as a conservative contributor after weathering fallout amid his past scandal involving Trump and a hot mic.
‘Real World: San Diego’ Alum Robin Hibbard Shares Health Update After Substance Abuse Struggles
Real World: San Diego alum and former The Challenge star Robin Hibbard is sharing a hopeful health update after a years-long battle with substance abuse. Hibbard, 46, shared the update in the comments...
Matthew McConaughey says ‘blood has been drawn’ during real-life fights with Woody Harrelson
And the actor tells EW that it “will be drawn again.”
“Rocky IV”’s Dolph Lundgren recalls meeting wife Emma Krokdal when he was 61 and she was 22
The actor detailed the early days of their relationship in new memoir “Fights Worth Fighting.”
How “Primetime” director convinced Robert Pattinson to play Chris Hansen: Four Lokos, gummies, and a late rewrite
Director Lance Oppenheim reveals the moment the actor decided to star in the film after initially boarding only as a producer.
Kit Harington has never met Leonardo DiCaprio but has an epic nickname for him
Harington’s nickname for DiCaprio might just be worth keeping.
Raines football's latest feat? 30 regular-season wins, and counting
Raines' football victory over Mandarin keeps several historic streaks going for the Vikings, and First Coast Varsity Weekly has the details.
Frank Ski launches weekly YouTube podcast ‘Frankly Speaking’
V-103 host Frank Ski has started a podcast, "Frankly Speaking," featuring interviews with politicians, celebrities and lifestyle experts. He records from his home.
“Interview With the Vampire” director says Oprah asked if he was upset she walked out of the film
“She thought it was evil, actually,” director Neil Jordan tells EW.
Jessica Lange gave strict condition to Ryan Murphy for returning to “American Horror Story” — and it’s not a ‘musical number’
The star revealed the one stipulation she had before agreeing to come back, and revealed she plays a secret fifth character on “AHS” season 13.
“Survivor” host Jeff Probst reacts to Dee and Rick Devens’ “Big Brother” success
Plus: We nominate the Survivor we’d like to see play next.
TV and streaming viewing picks for September 22, 2026: How to watch WNBA on ESPN
All Times Eastern College Basketball ACC Network Basketball Podcast — ACC Network, 5 p.m. College Football Florida Atlantic Weekly Press Conference — ESPN+, 11:45 a.m. Cincinnati Football Press Conference — ESPN+, noon Oklahoma Football Press Conference — SEC Network, noon Iowa State Football Press Conference — EPSN+, 12:55 p.m. B1G Live: Football Coaches Press Conferences…
Pat Boone calls out ‘friend’ Donald Trump for ‘schoolboy’ conduct: ‘Try being quiet’
The conservative entertainer has expressed concern for Trump and recommends he model himself after Ronald Reagan.
Travis Kelce says Taylor Swift looked ‘hot with a gun on her waist’ in Emmys cameo
The pop star played a rookie cop in an “Law & Order: SVU” sketch that investigated whether Swift would attend the awards show.
“Reacher” star Alan Ritchson feels like he’s ‘not supposed to be loved’ amid divorce from wife of 20 years
The actor star says he carried the feeling that he is “not worthy of love” into adulthood.
Carrot Top Overdosed at His Las Vegas Home During Health Crisis
Carrot Top is suspected to have suffered a drug overdose on Friday, Sept 18, at his Las Vegas home after he attempted suicide. TMZ reported that the comedian overdosed on prescription medication befor...
Sporting KC Weekly Schedule: Sept. 21-26, 2026
Sporting Kansas City will travel to Texas this weekend to take on Houston Dynamo FC at 7:30 p.m. CT on Saturday at Shell Energy Stadium. The Western Conference match-up will be available to watch in English and Spanish on Apple TV in addition to local radio coverage on Sports Radio
U.K.'s Official Charts Launches Subscription-Based PRO Platform For Music, Home Entertainment Movies
The Official Charts, the weekly U.K. platform tracking sales of music and movie digital and physical media sales, Sept. 21 launched the subscription-based PRO edition, which will take effect on Sept. 24. PRO provides direct access to the Official Charts Company’s sales data, and enables users to track performance across artists, tracks and film titles, … Continue reading "U.K.’s Official Charts Launches Subscription-Based PRO Platform For Music, Home Entertainment Movies"
When is “The Voice” season 30 on? Where to watch live and how voting works
Returning coaches Kelly Clarkson and Adam Levine are joined by two newcomers.
Meg Ryan and Jack Quaid make first mother-son red carpet appearance together
Ryan, who shared Jack with ex-husband Dennis Quaid, is also mother to daughter, Daisy.
Sylvester Stallone told Donald Trump ‘thank you and ciao’ after being appointed as ‘special ambassador’
Trump gave Stallone, who had no prior awareness, the title in January 2025.
Kenny Loggins reveals the 4 powerful words he wants written on his tombstone
And no, it’s not a “Footloose” or “Danger Zone” lyric.
Hayden Christensen makes rare public appearance with his and ex Rachel Bilson’s daughter
The father-daughter duo stepped out for the opening of the Lucas Museum of Narrative Art over the weekend.
Arnold Schwarzenegger’s 20 best roles, ranked
From unstoppable cyborgs to lovable oddballs, these are the best performances of Arnie’s more than 50-year acting career.
Presley Gerber detailed addiction treatment 6 months before his death: ‘I knew why I was there’
Gerber said “letting go of control didn’t come easy” in a touching post about his rehabilitation in March.
Jeff Probst clears up how the Open Era is different from regular “Survivor”
The host also gets into how the season 51 players and he reacted to coming off of “Survivor 50.”
Inside Presley Gerber’s Battle With Mental Health And Addiction Before Death At 27
Presley Gerber, son of supermodel Cindy Crawford and brother of actress Kaia Gerber, tragically passed away at age 27 in a rehab facility in California. He had been open about his struggles with menta...
Brevard County high school sports weekly schedule, Sept. 21-26
The Cape Coast Conference volleyball tournament headlines the week ahead for Brevard County high school sports.
How Hemp-THC businesses are bracing for a near total ban
Follow us to Tennessee where hemp farmers are already pivoting in the face of a state ban and soon, a looming federal ban on basically all THC-derived hemp products. Will Congress step in to save this $28 billion industry? Fact checking by Sierra Juarez.Your Next Listen — How would-be weed merchants hit a ‘grass ceiling’ Connect with The Indicator — Sign up for The Indicator’s weekly newsletter! — Buy the Planet Money book — Find our socials, YouTube and more! — For sponsor-free episodes, subscribe to NPR+ Support public media with NPR+ and enjoy perks for over 25 podcasts like this one. This show’s perks include sponsor-free listening. Learn more at plus.npr.org.
This Week’s Japanese Game Releases: Silent Hill: Townfall, GOBBLE, more
Silent Hill: Townfall for PlayStation 5 and PC, and GOBBLE for PlayStation 5, Switch 2, Switch, and PC are the highlights of this week’s Japanese video game releases.
Presley Gerber, son of Cindy Crawford and brother of Kaia Gerber, dies at 27
Presley was open about his struggles with addiction and mental health, sharing in 2025 his hope to find “a good community of people who can be good influences on me.”
Taylor Swift points to wedding ring, shouts, ‘That’s my husband!’ as Travis Kelce scores touchdown at Chiefs game
The newlywed music icon showed out for Kansas City’s big home game against the Indianapolis Colts at Arrowhead Stadium on Sunday.
CW@60: AI will change the economics of business more profoundly tha...
I have spent most of my working life watching technology change what it means to run a business.
Ke Huy Quan Reveals The “Life Changing” Gesture From Spielberg & Lucas When He Was A Kid
Ke Huy Quan was 12 years old when he made Indiana Jones and the Temple of Doom. In his new memoir, Never Say Die, excerpted in Entertainment Weekly, the Oscar-winning actor reveals that producer Georg...
Alan Ritchson says “Reacher” planned a white supremacist storyline until ‘someone got re-elected’
The star of the hit Amazon series says there were plans at one point to adapt Lee Child’s second ‘Reacher’ novel, ‘Die Trying.’
Jessica Chastain series shelved in wake of Charlie Kirk assassination finally gets 2027 release
“The Savant,” which stars Chastain as an investigator of extremist hate groups, was put on ice following the conservative activist’s killing.
Lesley-Anne Down says Burt Reynolds was obsessed with 3 things: ‘He wanted that extra… four inches or so’
The pair starred together in the 1980 heist movie “Rough Cut.”
Carrot Top Awake and ‘Breathing on His Own’ in Hospital Amid Health Crisis
Warning: The following post contains discussions of suicide. Carrot Top is reportedly awake and alert following a suicide attempt on Friday, Sept. 18. In a statement made to TMZ by a representative fo...
Business Agenda for September 20
Events for the tri-county area business community.
Ed Sheeran weeps onstage, admits to ‘making mistakes’ in first concert since Macklemore exit: ‘I’m so sorry’
The singer has been embroiled in controversy since Macklemore was removed for making pro-Palestine statements onstage.
“Lioness” season 3 just ended with a pair of game-changing cliffhangers
The Taylor Sheridan spy series has to return for a fourth season after that finale.
Arsenal Women Weekly Roundup: Man United draw exposes attacking concerns
It has been another frustrating week for Arsenal Women, although Smilla Holmberg ensured it ended with at least something to celebrate after her dramatic stoppage-time equaliser against Manchester Uni...
Entertainment Stars Jeon Won-ju, Go Ji-yong, Han So-hee Spark Controversies
Entertainment Stars Jeon Won-ju, Go Ji-yong, Han So-hee Spark Controversies Weekly roundup includes fee disputes, backlash, custody battle, and verbal misstep
UFC 331 Post-Fight Press Conference Video
Watch the UFC 331 Post-Fight Press Conference video here.
Chris McKenna Made Sure One Special Costar ‘Got Her Flowers’ Before ‘General Hospital’ Exit
Chris McKenna and Paige Herschell exited 'General Hospital' as Jack Brennan and Jacinda Bracken departed Port Charles in dramatic fashion this summer.
Sally Field says she doesn’t have ‘overt sexuality,’ so used this actress as inspiration for “Norma Rae”
The “Remarkably Bright Creatures” star said she typically played the tomboy in her early roles.
Snooki announces that she is cancer-free: ‘Thanks to all the doctors who helped me’
She was first diagnosed with stage 1 cervical cancer in February.
Martha Stewart’s Business Manager Keep Questioning Her Spend on This One Guilty Pleasure
Martha Stewart will always splurge on this one thing… The businesswoman and TV personality admitted she always finds room in the budget for plants while speaking to Richard Christiansen about his new ...
Deals: iPhone 18 Pros launch, refurbished iPhone 17 Pros are expensive, Galaxy Z8 foldables discounted
A refurbished 17 Pro Max costs as much as when it was new. The iPhone 18 Pro and 18 Pro Max went on sale this week in the US, along with 64 other countries...
Frankie Muniz’s estranged wife shares message about ‘perspective’ after actor’s ‘rock bottom’ post
The actor said on Friday that the past six weeks were like “a nightmare I’m praying to wake from.”
One Foot Down Reacts: We Like The Lines
With under nine hours to tonight’s kick, let’s take a quick peek at our weekly survey question at One Foot Down. If Notre Dame is going to be a championship caliber team, it’ll be on the backs of guys like linebacker Jaiden Ausberry, defensive end Bryce Young, safety Adon Shuler and linebacker Drayk Bowen. This […]
Christine Taylor breaks down the shockingly low pay for “Hey, Dude” cast
The actress says the Nickelodeon show didn’t make her rich.
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!
Emma Roberts says her son thinks she ‘rides on airplanes’ for work because she’s gone so often
Roberts shares 5-year-old son Rhodes with actor Garrett Hedlund.
Colorado Politics Calendar Sept. 21-27
CoPo’s weekly political calendar will help you find political and public-policy events throughout Colorado. It includes candidate and issue campaign events, public policy meetings, court hearings, state and local party conventions, assemblies, debates, rallies, parades, speaking engagements, traveling dignitary appearances, water meetings, book signings, county commission hearings, city council meetings and more. As a subscriber, […]
Health Journalists Visit Conservative Georgia District and Weigh AI Bioweapon Threat
KFF Health News journalists made the rounds on national and local media recently to discuss topical stories. Here’s a collection of their appearances.
Mind Your Manners: Kindness counts — and might provide surprising health benefits
Because I work closely with the medical community, I receive a weekly digest featuring the latest medical updates, developments, studies and hot topics from around the world. One recent article,
“Sweet Magnolias” canceled after 5 seasons at Netflix as star and creator reteam for new show
Creator Sheryl J. Anderson and star JoAnna Garcia Swisher are already working on a new series together.
Meghan McCain slams Aidy Bryant’s ‘cruel’ impression of her on “SNL”
“I didn’t find it funny,” the conservative personality complained of her portrayal on the show back in 2018.
University of Washington launches new Master of Science in Robotics
This autumn, the University of Washington (UW) is launching a Master of Science in Robotics, a 38-credit degree designed to meet the demands of one of the fastest-growing careers in technology.