Featured Research

from universities, journals, and other organizations

Heart responds differently to exercise in men vs. women

Date:
March 27, 2014
Source:
American College of Cardiology
Summary:
The formula for peak exercise heart rate that doctors have used for decades in tests to diagnose heart conditions may be flawed because it does not account for differences between men and women, according to research. The simple formula of "220 minus age" has been widely used to calculate the maximum number of heart beats per minute a person can achieve. Many people use it to derive their target heart rate during a workout. Doctors use it to determine how hard a patient should exercise during a common diagnostic test known as the exercise stress test. After analyzing more than 25,000 stress tests, the researchers found significant differences between men and women.

The formula for peak exercise heart rate that doctors have used for decades in tests to diagnose heart conditions may be flawed because it does not account for differences between men and women, according to research to be presented at the American College of Cardiology's 63rd Annual Scientific Session.

The simple formula of "220 minus age" has been widely used to calculate the maximum number of heart beats per minute a person can achieve. Many people use it to derive their target heart rate during a workout. Doctors use it to determine how hard a patient should exercise during a common diagnostic test known as the exercise stress test.

After analyzing more than 25,000 stress tests, the researchers found significant differences between men and women and developed an updated formula to reflect those nuances.

"The standard that's currently in use is somewhat outdated," said Thomas Allison, M.D., cardiologist and director of stress testing at Mayo Clinic, and senior author of the study. "We want to make sure that when people do the stress test, they have an accurate expectation of what a normal peak heart rate is. Every so often, you need to recalibrate what's considered normal."

The new formula can help people better optimize their workouts and also improve the accuracy of test results. Stress tests, which are commonly used to help diagnose conditions such as coronary heart disease, heart valve disease and heart failure, require patients to exercise near their top capacity while technicians monitor the patient's cardiac performance.

The researchers drew data from 25,000 patients who took stress tests at Mayo Clinic between 1993 and 2006. The sample included men and women 40 to 89 years of age who had no history of cardiovascular disease.

The study reveals that although everybody's peak heart rate declines with age, the decline is more gradual in women. As a result, the previous formula overestimates the peak heart rate younger women can achieve and underestimates the peak heart rate of older women.

Women in the age range of 40 to 89 years should expect their maximum heart rate to be 200 minus 67 percent of their age. In men, the formula is 216 minus 93 percent of their age. For women younger than 40, the relationship of heart rate to age may be different, as an insufficient number of tests on women younger than 40 were available to provide reliable results.

The study also showed that younger men have a lower resting heart rate and higher peak heart rate than women and that men's heart rates rise more dramatically during exercise and return to normal more quickly after stopping. The study did not investigate the physiological reasons behind the differences, although the researchers suggest hormones, especially testosterone, may play a role.

The previous formula was based on a study researchers now recognize as having serious limitations. For example, it included few women, a weakness common among older studies.

"It's logical that an equation developed 40 years ago based on a group that was predominantly men might not be accurate when applied to women today," Allison said. "But sometimes things just get stuck."

Changes since the 1970s in terms of average body weight, fitness levels and attitudes toward exercise -- particularly among women -- justify a re-evaluation of peak heart rate norms, Allison said. Other recent studies have offered updates to the formula, but this study uses a larger sample size and is the first to include data from both men and women.


Story Source:

The above story is based on materials provided by American College of Cardiology. Note: Materials may be edited for content and length.


Cite This Page:

American College of Cardiology. "Heart responds differently to exercise in men vs. women." ScienceDaily. ScienceDaily, 27 March 2014. <www.sciencedaily.com/releases/2014/03/140327100802.htm>.
American College of Cardiology. (2014, March 27). Heart responds differently to exercise in men vs. women. ScienceDaily. Retrieved September 1, 2014 from www.sciencedaily.com/releases/2014/03/140327100802.htm
American College of Cardiology. "Heart responds differently to exercise in men vs. women." ScienceDaily. www.sciencedaily.com/releases/2014/03/140327100802.htm (accessed September 1, 2014).

Share This




More Health & Medicine News

Monday, September 1, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

We've Got Mites Living In Our Faces And So Do You

We've Got Mites Living In Our Faces And So Do You

Newsy (Aug. 30, 2014) A new study suggests 100 percent of adult humans (those over 18 years of age) have Demodex mites living in their faces. Video provided by Newsy
Powered by NewsLook.com
Liberia Continues Fight Against Ebola

Liberia Continues Fight Against Ebola

AFP (Aug. 30, 2014) Authorities in Liberia try to stem the spread of the Ebola epidemic by raising awareness and setting up sanitation units for people to wash their hands. Duration: 00:41 Video provided by AFP
Powered by NewsLook.com
California Passes 'yes-Means-Yes' Campus Sexual Assault Bill

California Passes 'yes-Means-Yes' Campus Sexual Assault Bill

Reuters - US Online Video (Aug. 30, 2014) California lawmakers pass a bill requiring universities to adopt "affirmative consent" language in their definitions of consensual sex, part of a nationwide drive to curb sexual assault on campuses. Linda So reports. Video provided by Reuters
Powered by NewsLook.com
New Drug Could Reduce Cardiovascular Deaths

New Drug Could Reduce Cardiovascular Deaths

Newsy (Aug. 30, 2014) The new drug from Novartis could reduce cardiovascular deaths by 20 percent compared to other similar drugs. Video provided by Newsy
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins