fbpx
Connect with us

The Conversation

Heart rate zones aren’t a perfect measure of exercise intensity, but regularly getting your heart pumping is still important for fitness

Published

on

Heart rate zones aren't a perfect measure of exercise intensity, but regularly getting your heart pumping is still important for fitness

Regardless of the intensity of exercise you prefer, keeping a consistent routine can keep your heart healthy.
Klaus Vedfelt/DigitalVision via Getty Images

Jason Sawyer, Bryant University

Aerobic exercise like jogging, biking, swimming or is a fundamental way to maintain cardiovascular and overall health. The intensity of aerobic exercise is important to determine how much time you should spend in order to reap its .

As an exercise science researcher, I the American College of Sports Medicine's recommendation of a minimum of 150 minutes per of moderate aerobic exercise, or 75 minutes per week of high-intensity exercise. But what does exercise intensity mean?

There is a linear relationship between heart rate and exercise intensity, meaning as the exercise intensity increases, so does heart rate. Heart rate zone training, which uses heart rate as a measure of exercise intensity, has increased in popularity in recent years, partially due to the ubiquity of wearable heart rate technology.

The way exercise intensity is usually described is problematic because one person's “vigorous” may be another's “moderate.” Heart rate zone training tries to an objective measure of intensity by breaking it down into various zones. But heart rate can also be influenced by temperature, medications and stress levels, which may affect readings during exercise.

Advertisement

Heart rate and exercise intensity

The gold standard for determining aerobic exercise intensity is to measure the amount of oxygen consumed and carbon dioxide exhaled. However, this method is cumbersome because it requires people to wear a breathing mask to capture respiratory gases.

An easier way is to predict the person's maximum heart rate. This can be done with an equation that subtracts the person's age from 220. Although there is controversy surrounding the best way to calculate maximum heart rate, researchers suggest this method is still valid.

What happens when you reach your maximum heart rate?

The American College of Medicine outlines five heart rate zones based on a person's predicted heart rate maximum. Zone 1, or very light intensity, equals less than 57% of maximum heart rate; zone 2, or light intensity, is 57% to 63%; zone 3, or moderate intensity, is 64% to 76%; zone 4, or vigorous intensity, is 77% to 95%; and zone 5, or near-maximal intensity, is 96% to 100%.

However, other organizations have their own measures of exercise intensity, with varying ranges and descriptions. For example, Orange Theory their zone 2 training as 61% to 70% of maximum heart rate. Complicating matters even further, companies that produce heart rate monitors also have higher thresholds for each zone. For example, Polar's zone 2 is up to 70% of maximum heart rate, while the American College of Sports Medicine recommends a zone 2 of up to 63%.

Advertisement

Adapting heart rate zones

Zone training is based on the idea that how the body responds to exercise is at least in part determined by exercise intensity. These adaptations include increased oxygen consumption, important cellular adaptations and improved exercise performance.

Zone 2 has received a lot of attention from the fitness community because of its possible benefits. Performance coaches describe zone 2 as “light cardio,” where the intensity is low and the body relies mainly on fat to meet energy demands. Fats provide more energy to carbohydrates, but deliver it to cells more slowly.

Because fat is more abundant than carbohydrates in the body, the body responds to the cellular stress that exercise causes in muscle cells by increasing the number of mitochondria, or the energy-producing component of cells. By increasing the number of mitochondria, the body may become better at burning fat.

Person crouching, about to lift a barbell
Different types of exercise have different effects on your body.
Victor Freitas/Unsplash, CC BY-SA

On the other end of the spectrum of exercise intensity is high-intensity interval training, or HIIT. These workouts involve exercising at a high intensity for short durations, like an all-out sprint or cycle for 30 seconds to a minute, followed by a period of low intensity activity. This is repeated six to 10 times.

During this sort of high-intensity activity, the body primarily uses carbohydrates as a fuel source. During high-intensity exercise, the body preferentially uses carbohydrates because the energy demand is high and carbohydrates provide energy twice as fast as fats.

Advertisement

Some people who turn to exercise to lose fat may eschew high-intensity training for zone 2, as it's considered the “the fat burning zone.” This may be a misnomer.

Researchers have found that high-intensity interval training produces a similar increase in markers for mitochondria production when compared to longer, moderate aerobic training. Studies have also shown that high-intensity exercisers build muscle and improve insulin resistance and cardiovascular health similar to moderate-intensity exercisers, and they made these gains faster. The main trade-off was discomfort during bouts of high-intensity exercise.

Moderate- or high-intensity exercise?

With varying guidelines around heart rate zones and conflicting evidence on the potential benefits of training in each zone, exercisers may be left wondering what to do.

In order to yield the health benefits of exercise, the most important variable to consider is adhering to an exercise routine, regardless of intensity. Because the body adapts in similar ways to moderate- and high-intensity exercise, people can choose which intensity they like best or dislike the least.

Advertisement
Group of people smiling and running in a park
More important than exercise intensity is sticking to a consistent routine you enjoy.
Maskot/DigitalVision via Getty Images

Notice that the American College of Sports Medicine's recommendation for exercise falls under moderate intensity. This is equivalent to zone 3, or 64% to 76% of maximum heart rate, a range you can only meet in the upper levels of most zone 2 workouts. If you're not seeing desired results with your zone 2 workouts, try increasing your intensity to reach the moderate level.

A commonly reported reason for not exercising is a lack of time. For people short on time, high-intensity training is a good alternative to steady- cardiovascular exercise. For people who find exercising at such a high intensity uncomfortable, they can get the same benefit by doing moderate-intensity exercise for a longer period.The Conversation

Jason Sawyer, Associate Professor of Exercise and Movement Science, Bryant University

This article is republished from The Conversation under a Creative Commons license. Read the original article.

The Conversation

Grizzly bear conservation is as much about human relationships as it is the animals

Published

on

theconversation.com – Alexander L. Metcalf, Associate Professor of Human Dimensions of Natural Resources, University of Montana – 2024-04-16 07:32:53
If the government takes grizzly bears off the Endangered Species List, some states will likely introduce a hunting season.
Wolfgang Kaehler/LightRocket via Getty Images

Alexander L. Metcalf, University of Montana

Montanans know spring has officially arrived when grizzly bears emerge from their dens. But unlike the bears, the contentious debate over their future never hibernates. New research from my lab reveals how people's social identities and the dynamics between social groups may play a larger role in these debates than even the animals themselves.

Social scientists like me work to understand the human dimensions behind wildlife conservation and management. There's a cliché among wildlife biologists that wildlife management is really people management, and they're right. My research seeks to understand the psychological and social factors that underlie pressing environmental challenges. It is from this perspective that my team sought to understand how Montanans think about grizzly bears.

To list or delist, that is the question

In 1975, the grizzly bear was listed as threatened under the Endangered Species Act decades of extermination efforts and habitat loss that severely constrained their range. At that time, there were 700-800 grizzly bears in the lower 48 states, down from a historic 50,000. , there are about 2,000 grizzly bears in this area, and sometime in 2024 the U.S. Fish and Wildlife Service will decide whether to maintain their protected status or begin the delisting .

Advertisement

Listed species are managed by the federal government until they have recovered and management responsibility can return to the states. While listed, federal prevents hunting of the animal and destruction of grizzly bear habitat. If the animal is delisted, some states intend to implement a grizzly bear hunting season.

People on both sides of the delisting debate often use logic to try to convince others that their position is right. Proponents of delisting say that hunting grizzly bears can help reduce conflict between grizzly bears and humans. Opponents of delisting counter that state agencies cannot be trusted to responsibly manage grizzly bears.

But debates over wildlife might be more complex than these arguments imply.

Identity over facts

Humans have survived because of our evolved ability to cooperate. As a result, human brains are hardwired to favor people who are part of their social groups, even when those groups are randomly assigned and the group members are anonymous.

Advertisement

Humans perceive reality through the lens of their social identities. People are more likely to see a foul committed by a rival sports team than one committed by the team they're rooting for. When randomly assigned to be part of a group, people will even overlook subconscious racial biases to favor their fellow group members.

Your social identities influence how you interpret your own reality.

can leverage social identities to inspire cooperation and collective action. For example, during the pandemic, people with strong national identities were more likely to physically distance and public policies.

But the forces of social identity have a dark side, too. For example, when people think that another “out-group” is threatening their group, they tend to assume members of the other group hold more extreme positions than they really do. Polarization between groups can worsen when people convince themselves that their group's positions are inherently right and the other group's are wrong. In extreme instances, group members can use these beliefs to justify immoral treatment of out-group members.

Empathy reserved for in-group members

These group dynamics help explain people's attitudes toward grizzly bears in Montana. Although property damage from grizzly bears is extremely rare, affecting far less than 1% of Montanans each year, grizzly bears have been known to break into garages to access food, prey on free-range livestock and sometimes even maul or kill people.

Advertisement

People who hunt tend to have more negative experiences with grizzly bears than nonhunters – usually because hunters are more often living near and moving through grizzly bear habitat.

Two mean wearing jackets and holding shotguns as they walk across a grassy field with a dog.
When hunters hear grizzly bear conflict stories from other hunters, they might favor grizzlies less, even if they've never had a negative experience with one themselves.
Karl Weatherly/DigitalVision via Getty Images

In a large survey of Montana residents, my team found that one of the most important factors associated with negative attitudes toward grizzly bears was whether someone had heard stories of grizzly bears causing other people property damage. We called this “vicarious property damage.” These negative feelings toward grizzly bears are highly correlated with the belief that there are too many grizzly bears in Montana already.

But we also found an interesting wrinkle in the data. Although hunters extended empathy to other hunters whose properties had been damaged by grizzly bears, nonhunters didn't show the same courtesy. Because property damage from grizzly bears was far more likely to affect hunters, only other hunters were able to put themselves in their shoes. They felt as though other hunters' experiences may as well have happened to them, and their attitudes toward grizzly bears were more negative as a result.

For nonhunters, hearing stories about grizzly bears causing damage to hunters' property did not affect their attitudes toward the animals.

Advertisement

Identity-informed conservation

Recognizing that social identities can play a major role in wildlife conservation debates helps untangle and perhaps prevent some of the conflict. For those wishing to build consensus, there are many psychology-informed strategies for improving relationships between groups.

For example, conversations between members of different groups can help people realize they have shared values. Hearing about a member of your group helping a member of another group can inspire people to extend empathy to out-group members.

Conservation groups and wildlife managers should take care when developing interventions based on social identity to prevent them from backfiring when applied to wildlife conservation issues. Bringing up social identities can sometimes cause unintended division. For example, partisan can unnecessarily divide people on environmental issues.

Wildlife professionals can reach their audience more effectively by matching their message and messengers to the social identities of their audience. Some conservation groups have seen uniting community members who might otherwise be divided around a shared identity associated with their love of a particular place. The conservation group Swan Valley Connections has used this strategy in Montana's Swan Valley to reduce conflict between grizzly bears and local residents.

Advertisement

Group dynamics can foster cooperation or create division, and the debate over grizzly bear management in Montana is no exception. Who people are and who they care about drives their reactions to this large carnivore. Grizzly bear conservation efforts that unite people around shared identities are far more likely to succeed than those that remind them of their divisions.The Conversation

Alexander L. Metcalf, Associate Professor of Human Dimensions of Natural Resources, University of Montana

This article is republished from The Conversation under a Creative Commons license. Read the original article.

Continue Reading

The Conversation

In the age of cancel culture, shaming can be healthy for online communities – a political scientist explains when and how

Published

on

theconversation.com – Jennifer Forestal, Assistant Professor of Political Science, Loyola Chicago – 2024-04-16 07:32:06
Public shaming can uphold online community norms.
bo feng/iStock via Getty Images

Jennifer Forestal, Loyola University Chicago

“Cancel culture” has a bad reputation. There is growing anxiety over this practice of publicly shaming people online for violating social norms ranging from inappropriate jokes to controversial business practices.

Online shaming can be a wildly disproportionate response that violates the privacy of the shamed while offering them no good way to defend themselves. These consequences some critics to claim that online shaming creates a “hate storm” that destroys lives and reputations, leaves targets with “permanent digital baggage” and threatens the fundamental right to publicly express yourself in a democracy. As a result, some scholars have declared that online shaming is a “moral wrong and social ill.”

But is online public shaming necessarily negative? I'm a political scientist who studies the relationship between digital technologies and democracy. In my research, I show how public shaming can be a valuable tool for democratic accountability. However, it is more likely to these positive effects within a clearly defined community whose members have many overlapping connections.

Advertisement

When shaming helps

Public shaming is a “horizontal” form of social sanctioning, in which people hold one another responsible for violating social norms, rather than appealing to higher authorities to do so. This makes it especially useful in democratic societies, as well as in cases where the shamers face power imbalances or lack access to formal authorities that could hold the shamed accountable.

For example, public shaming can be an effective strategy for challenging corporate power and behavior or maintaining journalistic norms in the face of plagiarism. By harnessing social pressure, public shaming can both motivate people to change their behavior and deter future violations by others.

Public shaming has a long history.

But public shaming generally needs to occur in a specific social context to have these positive effects. First, everyone involved must recognize shared social norms and the shamer's authority to sanction violations of them. Second, the shamed must care about their reputation. And third, the shaming must be accompanied by the possibility of reintegration, allowing the shamed to and be welcomed back into the fold.

This means that public shaming is more likely to deliver accountability in clearly defined communities where members have many overlapping connections, such as schools where all the parents know one another.

Advertisement

In communal spaces where people frequently into each other, like workplaces, it is more likely that they understand shared social norms and the obligations to follow them. In these environments, it is more likely that people care about what others think of them, and that they know how to apologize when needed so that they can be reintegrated in the community.

Communities that connect

Most online shamings, however, do not take place in this kind of positive social context. On the social platform X, previously known as Twitter, which many high-profile public shamings, users generally lack many shared connections with one another. There is no singular “X community” with universally shared norms, so it is difficult for users to collectively sanction norm violations on the platform.

Moreover, reintegration for targets of shamings on X is nearly impossible, since it is not clear to what community they should apologize, or how they should do so. It should not be surprising, then, that most highly publicized X shamings – like those of PR executive Justine Sacco, who was shamed for a racist tweet in 2013, and Amy Cooper, the “Central Park Karen” – tend to degenerate into campaigns of harassment and stigmatization.

But just because X shamings often turn pathological does not mean all online shamings do. On Threadless, an online community and e-commerce site for artists and designers, users effectively use public shaming to police norms around intellectual property. Wikipedians' use of public “reverts” – reversals of edits to entries – has helped enforce the encylopedia's standards even with anonymous contributors. Likewise, Black Twitter has long used the practice of public shaming as an effective mechanism of accountability.

Advertisement

What sets these cases apart is their community structure. Shamings in these contexts are more productive because they occur within clearly defined groups in which members have more shared connections.

Acknowledging these differences in social context helps clarify why, for example, when a Reddit user was shamed by his subcommunity for posting an inappropriate , he accepted the rebuke, apologized and was welcomed back into the community. In contrast, those shamed on X often issue vague apologies before disengaging entirely.

The scale and speed of social media can change the dynamics of public shaming when it occurs online.

Crossing online borders

There are still very real consequences of moving public shaming online. Unlike in most offline contexts, online shamings often play out on a massive scale that makes it more difficult for users to understand their connections with one another. Moreover, by creating opportunities to expand and overlap networks, the internet can blur community boundaries in ways that complicate the practice of public shaming and make it more likely to turn pathological.

For example, although the Reddit user was reintegrated into his community, the shaming soon spread to other subreddits, as well as national outlets, which ultimately led him to delete his Reddit account altogether.

Advertisement

This example suggests that online public shaming is not straightforward. While shaming on X is rarely productive, the practice on other platforms, and in offline spaces characterized by clearly defined communities such as college campuses, can provide important public .

Shaming, like other practices of a healthy democracy, is a tool whose value depends on how it's used.The Conversation

Jennifer Forestal, Assistant Professor of Political Science, Loyola University Chicago

This article is republished from The Conversation under a Creative Commons license. Read the original article.

Advertisement
Continue Reading

The Conversation

Deepfake detection improves when using algorithms that are more aware of demographic diversity

Published

on

theconversation.com – Siwei Lyu, Professor of Computer Science and Engineering; Director, UB Forensic Lab, at Buffalo – 2024-04-16 07:31:48
Deepfake detection software may unfairly target people from some groups.
JLco – Ana Suanes/iStock via Getty Images

Siwei Lyu, University at Buffalo and Yan Ju, University at Buffalo

Deepfakes – essentially putting words in someone else's mouth in a very believable way – are becoming more sophisticated by the day and increasingly hard to spot. Recent examples of deepfakes include Taylor Swift nude images, an audio recording of President Joe Biden telling New Hampshire not to vote, and a video of Ukrainian President Volodymyr Zelenskyy calling on his troops to lay down their arms.

Although companies have created detectors to spot deepfakes, studies have found that biases in the data used to train these tools can to certain demographic groups being unfairly targeted.

a hand holds a smartphone with text on it in front of a screen with a man in front of a lectern
A deepfake of Ukraine President Volodymyr Zelensky in 2022 purported to show him calling on his troops to lay down their arms.
Olivier Douliery/AFP via Getty Images

My team and I discovered new methods that improve both the fairness and the accuracy of the algorithms used to detect deepfakes.

To do so, we used a large dataset of facial forgeries that lets researchers like us train our deep-learning approaches. We built our work around the -of-the-art Xception detection algorithm, which is a widely used foundation for deepfake detection and can detect deepfakes with an accuracy of 91.5%.

Advertisement

We created two separate deepfake detection methods intended to encourage fairness.

One was focused on making the algorithm more aware of demographic diversity by labeling datasets by gender and race to minimize errors among underrepresented groups.

The other aimed to improve fairness without relying on demographic labels by focusing instead on features not visible to the human eye.

It turns out the first method worked best. It increased accuracy rates from the 91.5% baseline to 94.17%, which was a bigger increase than our second method as well as several others we tested. Moreover, it increased accuracy while enhancing fairness, which was our main focus.

Advertisement

We believe fairness and accuracy are crucial if the public is to accept artificial intelligence technology. When large language models like ChatGPT “hallucinate,” they can perpetuate erroneous information. This affects public trust and safety.

Likewise, deepfake images and can undermine the adoption of AI if they cannot be quickly and accurately detected. Improving the fairness of these detection algorithms so that certain demographic groups aren't disproportionately harmed by them is a key aspect to this.

Our research addresses deepfake detection algorithms' fairness, rather than just attempting to balance the data. It offers a new approach to algorithm design that considers demographic fairness as a core aspect.The Conversation

Siwei Lyu, Professor of Computer Science and Engineering; Director, UB Media Forensic Lab, University at Buffalo and Yan Ju, Ph.D. Candidate in Computer Science and Engineering, University at Buffalo

This article is republished from The Conversation under a Creative Commons license. Read the original article.

Advertisement
Continue Reading

News from the South

Trending