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Heart rate & heart rate variability population values

Despite the fact that we highly recommend focusing on relative changes over time, in this post we provide an overview of normal values, which we advise using only to satisfy your curiosity. In particular, we will be looking at HR and rMSSD data. Most of the data was acquired using 60 seconds measurements in the morning. We will be looking only at macro differences (e.g. very big age groups), because otherwise we end up with a sample which is just too small to derive any meaningful conclusion.

The Journalist and the Pharma Bro

At home later that night, she couldn’t sleep; her Fitbit measured her resting heart rate at 10 beats higher for a week afterward. “I still was in denial about it, but this really hit me hard,” she says of Shkreli’s sudden jailing.

Harnessing wearable device data to improve state-level real-time surveillance of influenza-like illness in the USA: a population-based study - The Lancet Digital Health

Our mchange models were better at predicting change with a 1-week lag compared with a 1-week lead. It is possible that an ILI infection results in an elevated RHR for several weeks after initial infection. Previous studies have also indicated that an elevated heart rate can occur before symptom onset.16 Since influenza has an incubation period of 1–4 days, there is only a short opportunity to identify infections before symptom onset. However, since individuals with febrile respiratory illness typically seek care 3–8 days after symptom onset,18 it is conceivable that ILI cases could be identified via sensor data earlier than through traditional, clinic-based ILI surveillance. Early identification via our method might be more likely if rates were predicted at a daily, rather than weekly, rate.

Harnessing wearable device data to improve state-level real-time surveillance of influenza-like illness in the USA: a population-based study - The Lancet Digital Health

The impact of infections on an individual's RHR has been documented in several studies. One study found ill participants had RHRs that were elevated by 2·02–4·66 SD above their normal measurements.16 A study that examined 27 young men with acute febrile infections found that heart rates increased by 8·5 bpm per every 1°C increase in temperature.11 Similarly, a study among children with acute infections found that heart rate rose by 9·9–14·1 bpm for every 1°C increase in temperature, with higher increases in younger children.17 These studies indicate that infections can increase heart rate, probably due to increased body temperature and inflammatory responses as the body fights off an infection.

Fragmented physical activity linked to greater mortality risk -- ScienceDaily

The researchers found that for each 10 percent higher activity fragmentation there was a 49 percent increase in the risk of mortality. The researchers defined activity fragmentation as the probability of transitioning from an active state to a sedentary state for each participant, so shorter average activity periods meant higher fragmentation. The researchers also analyzed the duration of each participant's bouts of activity, and found that "percent of activity spent in bouts of less than five minutes" appeared to be another good marker of mortality risk. Each additional 10 percent of active time spent in such short bouts was associated with a 28 percent increase in the chance of mortality. Percent of active time spent in 5- to 10-minute bouts was not a significant indicator of mortality risk.

Your circle of friends is more predictive of your health, study finds -- ScienceDaily

Handing someone a means to track their steps and monitor their health in the hopes that their health improves simply may not be enough to see meaningful or significant results. Those employers, Chawla said, would benefit from encouraging employees to build a platform to post and share their experiences with each other. Social network structure helps complete the picture of health and well-being. […]"When we hear that health and wellness programs driven by wearables at places of employment aren't working, we should be asking, is it because we're just taking a single dimensional view where we just give the employees the wearables and forget about it without taking the step to understand the role social networks play in health?"

Your circle of friends is more predictive of your health, study finds -- ScienceDaily

Social network structure provided significant improvement in predicting one's health and well-being compared to just looking at health behavior data from the Fitbit alone. For example, when social network structure is combined with the data derived from wearables, the machine learning model achieved a 65 percent improvement in predicting happiness, 54 percent improvement in predicting one's self-assessed health prediction, 55 percent improvement in predicting positive attitude, and 38 percent improvement in predicting success. "This study asserts that without social network information, we only have an incomplete view of an individual's wellness state, and to be fully predictive or to be able to derive interventions, it is critical to be aware of the social network structural features as well," Chawla said.

Only 1115 people?!

They wanted to find out if interval training might match a continuous moderate intensity workout for overall weight loss (total absolute fat mass) and reductions in percentage body fat-the percentage of fat that makes up body weight-despite taking less time to do. Interval training describes intermittent intense effort, interspersed with recovery periods. The two most common types are high intensity interval training, or HIIT for short, which includes various exercises; and sprint interval training, which includes running, jogging, speed walking, and cycling. So they searched research databases for relevant studies that directly or indirectly compared interval training with continuous moderate intensity exercise over a period of at least four weeks. The data from 41 studies involving 1115 people were combined for thematic analysis and the results data from 36 studies involving 1012 people were pooled. Both interval training and a continuous workout reduced overall weight and percentage body fat, irrespective of starting weight or gender, the findings showed.

Do differences in gait predict the risk of developing depression in later life? -- ScienceDaily

Gait parameters and mental health both have significant impacts on functional status in later life. The study's findings suggest that gait problems may represent a potentially modifiable risk factor for depression.

will.i.am on personal data ownership

Personal data needs to be regarded as a human right, just as access to water is a human right. The ability for people to own and control their data should be considered a central human value. The data itself should be treated like property and people should be fairly compensated for it.

WillIAm-on-consumer-health-data-services

Today, my gadgets may count my steps, but they aren’t seeing the big picture: what I ate, how I felt, what my blood pressure is. New services, built from the point of view of the consumer, will benefit me by sharing and interconnecting my own data, rather than selling it on. When more trust is established, my personal “agent” or “assistant” should merge relevant things together that are currently just disconnected data points.

BARBARIANS AT THE GATE: CONSUMER-DRIVEN HEALTH DATA COMMONS AND THE TRANSFORMATION OF CITIZEN SCIENCE

A few state court cases have found patients own their medical records under specific circumstances.118 Unfortunately, the pertinent body of state medical records law generally applies in traditional healthcare settings and seemingly does not govern commercial providers of PHD devices and services, such as purveyors of medical and fitness devices. Courts do not recognize an individual property right in personal information such as one’s name, address, and social security number.119 Commercial databases that hold such information are generally treated as the property of the companies that compiled them.120 In a famous case121 where plaintiffs sought to block a company from disclosing their personal information by selling its mailing lists, Vera Bergelson notes an implicit judicial bias “that, to the extent personal information may be viewed as property, that property belongs to the one who collects it.”122 This bias— if it exists—is reminiscent of the ancient res nullius doctrine from natural resource law, which treated assets such as subsurface mineral deposits and wild animals as unowned until somebody discovers and captures (takes possession of) them.123 “Rarely used today, it let private owners stake claims as in the Klondike gold rush.”124

BARBARIANS AT THE GATE: CONSUMER-DRIVEN HEALTH DATA COMMONS AND THE TRANSFORMATION OF CITIZEN SCIENCE

This article explores how these mechanisms, imbedded in major federal research and privacy regulations, enshrine institutional data holders—entities such as hospitals, research institutions, and insurers that store people’s health data—as the prime movers in assembling large-scale data resources for research and public health. They rely on approaches—such as de-identification of data and waivers of informed consent—that are increasingly unworkable going forward. They shower individuals with unwanted, paternalistic protections—such as barriers to access to their own research results—while denying them a voice in what will be done with their data.

BARBARIANS AT THE GATE: CONSUMER-DRIVEN HEALTH DATA COMMONS AND THE TRANSFORMATION OF CITIZEN SCIENCE

Data resources are a central currency of twenty-first-century science, and the question is, “Who will control them?”

All of Us enrollees can now share health data from their Fitbit accounts with researchers | MobiHealthNews

“Collecting real-world, real-time data through digital technologies will become a fundamental part of the program,” Eric Dishman, director of the All of Us Research Program, said in a statement. “This information in combination with many other data types will give us an unprecedented ability to better understand the impact of lifestyle and environment on health outcomes and, ultimately, develop better strategies for keeping people healthy in a very precise, individualized way.”

Heart rate variability: Get to know what it brings to the fitness party

"It's the start of our focus on how sensors can be applied to wellness. HRV, which is what the Relax app is based on, is a new metric for us which took a lot of algorithmic development."

Heart rate variability: Get to know what it brings to the fitness party

Bottom line, it's an exciting time that more wearables are being able to tap into heart rate variability whether it's for improving fitness or just being able to know when you're feeling a bit stressed. This is really just the start of the relationship between the two, so don't be surprised if more HRV tracking devices are on their way over in the not too distant future.

Deep sleep may act as fountain of youth in old age | EurekAlert! Science News

"The parts of the brain deteriorating earliest are the same regions that give us deep sleep," said article lead author Mander, a postdoctoral researcher in Walker's Sleep and Neuroimaging Laboratory at UC Berkeley. Aging typically brings on a decline in deep non-rapid eye movement (NREM) or "slow wave sleep," and the characteristic brain waves associated with it, including both slow waves and faster bursts of brain waves known as "sleep spindles." Youthful, healthy slow waves and spindles help transfer memories and information from the hippocampus, which provides the brain's short-term storage, to the prefrontal cortex, which consolidates the information, acting as the brain's long-term storage. "Sadly, both these types of sleep brain waves diminish markedly as we grow old, and we are now discovering that this sleep decline is related to memory decline in later life," said Winer, a doctoral student in Walker's lab. Another deficiency in later life is the inability to regulate neurochemicals that stabilize our sleep and help us transition from sleep to waking states. These neurochemicals include galanin, which promotes sleep, and orexin, which promotes wakefulness. A disruption to the sleep-wake rhythm commonly leaves older adults fatigued during the day but frustratingly restless at night, Mander said. Of course, not everyone is vulnerable to sleep changes in later life: "Just as some people age more successfully than others, some people sleep better than others as they get older, and that's another line of research we'll be exploring," Mander said. Meanwhile, non-pharmaceutical interventions are being explored to boost the quality of sleep, such as electrical stimulation to amplify brain waves during sleep and acoustic tones that act like a metronome to slow brain rhythms.

Fitbit charts a wild heart and a calming mind

Humans rely on two feats of engineering, each astonishing in its own right. First, the body is endowed with an ability to constantly and instantly adjust to changing conditions. And, second, the body has an equally constant and instantaneous capacity to suppress awareness of those adjustments.

Fitbit creates research library with Fitabase, publishes results of corporate wellness study | MobiHealthNews

The library currently has 163 different published studies that mention using a Fitbit (or a few of them) as part of their study design. The pace of research using the wearables has been accelerating every year, Ramirez said, posing what Fitabase believed was a need for a comprehensive library. “So we wanted to make it a public resource where anyone who wants to explore Fitbit research can have a one-stop shop. It’s meant to be a library down the street, and it will continue to grow as people do more research.”

Fitness trackers do not increase activity enough to noticeably improve health | Society | The Guardian

The participants were assigned to one of four groups – a control group which had no tracker, a group which wore a Fitbit Zip device and the two final groups were given trackers and also offered financial rewards, either cash incentives for themselves or donations to charity for the first six months of the trial.[…] The researchers also measured participants’ levels of moderate-to-vigorous physical activity (MVPA) per week as well as their weight, blood pressure and cardio-respiratory fitness at the start of the study and six and 12 months later. They found that during the first six months of the study, only participants in the cash incentive group recorded increases in physical activity. The mean daily step count among wearers was 11,010 steps in the cash group, 9,280 in the charity group, and 8,550 in the Fitbit group. After a year, those in the cash incentive group had returned to the same levels of physical activity that they recorded at the start of the trial. Advertisement But by contrast, those in the Fitbit group showed improved levels of physical activity, recording an average of an additional 16 minutes of MVPA per week than they did at the start of the trial. However, the authors said that this increase was “probably not enough to generate noticeable improvements in any health outcomes”. They also found that Fitbit and charity participants showed similar step counts to when they were measured at six months.

Fitbit numbers

While the entire industry saw a bump during last year’s holiday season, companies such as Jawbone, Garmin, and Samsung saw their wearable sales decline quickly after Christmas. Fitbit’s never dropped to their pre-holiday levels, and began ramping up again this spring. In a regulatory filing submitted to the Securities and Exchange Commission last month, Fitbit says it sold 20.8 million devices between September 2009 and the end of this March, 10.9 million of which it sold in 2014. People are seeking out Fitbit products specifically When people buy Fitbit products online, the most common place they’re doing it is on the company’s own website. More than 43 percent of Fitbit sales take place on Fitbit.com, slightly edging out Amazon, which accounts for 40 percent of online sales of Fitbit devices. This likely means that many people know they want a Fitbit before they go to make a purchase, rather than searching on Amazon and choosing between brands. For Fitbit, it has the added advantage of allowing the company to avoid splitting revenue with a retail partner.

@elerianm says too much data dilutes the experience

Multiple metrics can confuse rather than enlighten; and they can add to a sense of underachievement. My Fitbit, even though it’s the most basic model, goes beyond measuring steps and miles. It also claims to be able to tell me how many calories I have burned and the number of “active minutes” in the day -- and it sets a daily target for each. I have no idea how I am supposed to internalize all these data points, including their order of importance. So I find myself pursuing multiple objectives that are highly correlated but, frustratingly, are not sufficiently linear in their relationship -- adding to the potential for performance anxiety.

The Apple Watch fails one key fitness test

That’s a much bigger problem than anybody seems to be acknowledging.For one thing, that fact makes the Apple Watch the only fitness tracker on the market that can’t track your sleep. One of the great joys of the Up band, Fitbit, and other bands is that they track not just your steps, but also your cycles of deep and light sleep. Not the Watch. For a device so thoroughly designed to help monitor your physical well-being, that omission is a heart-breaker.And if the watch is on your nightstand, you can’t exploit its brilliant wrist-tapping feature as a silent alarm that won’t wake your partner.
When I hit thirty-five thousand steps a day, Fitbit sent me an e-badge, and then one for forty thousand, and forty-five thousand. Now I’m up to sixty thousand, which is twenty-five and a half miles. Walking that distance at the age of fifty-seven, with completely flat feet while lugging a heavy bag of garbage, takes close to nine hours—a big block of time, but hardly wasted. I listen to audiobooks, and podcasts. I talk to people. I learn things: the fact, for example, that, in the days of yore, peppercorns were sold individually and, because they were so valuable, to guard against theft the people who packed them had to have their pockets sewed shut. At the end of my first sixty-thousand-step day, I staggered home with my flashlight knowing that I’d advance to sixty-five thousand, and that there will be no end to it until my feet snap off at the ankles. Then it’ll just be my jagged bones stabbing into the soft ground. Why is it some people can manage a thing like a Fitbit, while others go off the rails and allow it to rule, and perhaps even ruin, their lives?