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New research suggests that vigorous exercise may help lower mortality rates related to dementia. Suhaimi Abdullah/NurPhoto via Getty Images
  • More than 55 million people globally have dementia. As of 2019, about 1.62 million deaths worldwide were attributed to dementia.
  • Dementia symptoms can be managed, and life expectancy can be increased through the use of medications and lifestyle changes.
  • A new study found that vigorous physical activity can help lower dementia mortality rates.

A group of researchers recently published a study in the Lancet Healthy Longevity, suggesting that participating in vigorous physical activity can help lower dementia mortality rate compared to moderate physical activity.

More than 55 million people around the world have dementia, which is the symptom of a series of neurological conditions affecting the brain. The most common type of dementia is Alzheimer’s disease.

As of 2019, researchers found about 1.62 million deaths globally were attributed to dementia, making it the fourth largest cause of death among individuals 70 or older.

Although there is currently no cure for most types of dementia nor a way to reverse its impact on the brain, symptoms can be managed, and life expectancy can be increased through medications and certain lifestyle changes.

One such lifestyle change is getting more physical activity.

Dr. Borja del Pozo Cruz is a principal researcher in applied health sciences at the University of Cadiz and INIBiCA in Spain, an adjunct associate professor in the Department of Sports Science and Clinical Biomechanics at the University of Southern Denmark, and the lead author of this study.

Dr. Cruz said the researchers decided to examine the difference between moderate and vigorous physical activity and dementia-related mortality because the disease is quite prevalent, and physical activity is often recommended as a means of prevention of Alzheimer’s disease.

“However, guidelines are generic and do lack direction as to how much and what to do to maximize the benefits of physical activity,” Dr. del Pozo Cruz told Medical News Today.

A study presented at the American Academy of Neurology’s 74th Annual Meeting in 2022 reported that those who actively engaged in cardiorespiratory fitness reduced their overall dementia risk by 33%.

Research published in September 2022 found that only walking 4,000 steps a day could reduce a person’s dementia risk by 25%.

A study published in June 2022 stated that physical activity could help lower the incidence of all-cause dementia and Alzheimer’s disease, even in longer follow-ups.

For this study, researchers gathered data from 22 consecutive waves of the U.S. National Health Interview Survey from 1997 to 2018, for a total of more than 91,0000 study participants ages 68 or older.

During the interview surveys, participants were asked to self-report the frequency and type of physical activity they were doing.

Survey participants were asked to detail how often they performed light or moderate leisure-time physical activities that would cause only light sweating or a slight to moderate increase in breathing or heart rate and how long they normally perform these activities.

According to the National Heart, Lung, and Blood Institute, some examples of moderate physical activities are:

  • bicycling
  • swimming
  • water aerobics
  • social dancing
  • volleyball
  • jumping rope

They were then asked the same two questions regarding vigorous leisure-time physical activities that would cause heavy sweating or large increases in breathing or heart rate.

Types of vigorous physical activity include:

  • running/jogging
  • fast or hill bicycling
  • circuit weight training
  • fitness boxing
  • tennis
  • aerobics

Researchers then linked survey participants to the National Death Index until December 31, 2019, looking for anyone who had an Alzheimer’s disease-related mortality.

Scientists found 2,176 study participants died due to Alzheimer’s disease as the leading cause.

For participants who self-reported doing moderate physical activity, the researchers did not find a significant association with Alzheimer’s disease-related mortality.

“[It] could be that moderate intensity is not enough to elicit an optimal response to affect Alzheimer’s disease or its prevention,” Dr. del Pozo Cruz said. “It could also be that [the] question to collect moderate activity did also include some forms of lighter activities.”

However, for participants who participated in vigorous physical activity, scientists could identify a minimal amount of 40 minutes per week and an optimal amount of 140 minutes per week for reducing Alzheimer’s disease-related death.

“I think [the message] is clear — do engage in vigorous physical activity to maximize the chances of preventing Alzheimer’s disease, and possibly a number of other health benefits will also appear,” Dr. del Pozo Cruz said.

However, “[w]e need to replicate the study with objective measures of the exposure (i.e. physical activity),” he cautioned. “Until then [it] is difficult to make definitive conclusions about how intensity is crucial for Alzheimer’s disease.”

MNT also spoke about this study with Ryan Glatt, senior brain health coach and director of the FitBrain Program at Pacific Neuroscience Institute in Santa Monica, CA.

Glatt said that this study lends a greater understanding of exercise recommendations for those at high risk for Alzheimer’s disease and may demonstrate that not everyone should get the same exercise recommendations.

“Different intensities of exercise may impact the benefits gained as the result of exercise interventions. More research is needed to better understand the role of acute variables of exercise programs, such as intensity, frequency, type, and duration, in populations with variable risk factors. Such research would aid in more individualized exercise recommendations for dementia prevention, among other desired health outcomes.”

– Ryann Glatt

MNT asked Glatt for his tips on what types of physical activity people should be doing to help hopefully prevent dementia and/or decrease their mortality risk from these diseases.

He said that everyone should try to adhere — at the minimum — to the Physical Activity Guidelines for Americans.

“These guidelines state that individuals should aim for 150–300 minutes/per week of moderate-to-vigorous physical activity, with additional sessions of two to three days per week of strength training and two to three days per week of neuromotor training — balance, skill-based, or coordinative exercise,” Glatt detailed.

“These guidelines provide a range, which is important to keep in mind when considering exercise recommendations,” Glatt noted.