Participating in vigorous physical activity reduces Alzheimer’s disease-related death compared to moderate physical activity. Scientists identified 40 minutes minimum and 140 optimally of vigorous physical activity per week to lower risk.
Dr. Borja del Pozo Cruz and his research team have released a new study on how physical activity affects dementia risk. Dr. Cruz is principal researcher in applied health sciences at the University of Cadiz and INIBiCA in Spain and adjunct associate professor in the Department of Sports Science and Clinical Biomechanics at the University of Southern Denmark.
As lead author of this study, Dr. Cruz 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 stepsTrusted Source 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 incidenceTrusted Source of all-cause dementia and Alzheimer’s disease, even in longer follow-ups.
Vigorous vs. moderate physical activity
For this study, researchers gathered data from 22 consecutive waves of the U.S. National Health Interview SurveyTrusted Source 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 InstituteTrusted Source, 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 IndexTrusted Source 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.”