Staying Active Mid-Age Boosts Women's Health Later - Neuroscience News

Few longitudinal studies have measured physical activity at more than one time point and examined the long-term causal effects of exercise.

In the new study, researchers used data collected at three-year intervals beginning in 1996 from 11,336 participants in the Australian Longitudinal Study on Women's Health.

Women were born in 1946 through 1951, making them 47 to 52 years old at the study outset. Participants were classified as either meeting WHO physical activity guidelines — of 150 minutes of activity a week — consistently throughout the fifteen-year exposure period, not initially meeting the guidelines but starting to meet them at age 55, 60 or 65, or never meeting the guidelines.

Health-related quality of life was assessed using the physical health composite score (PCS) and mental health composite score (MCS) from the Short Form 36 Health Survey, which includes 36 questions about functional health and well-being.

On average, people who consistently met physical activity guidelines and those who first started to meet guidelines at age 55 had a three-point higher PCS (46.93 [95% CI 46.32 to 47.54] and 46.96 [95% CI 45.53 to 48.40], respectively), compared to those that did not meet physical activity guidelines (43.90 [95% CI 42.79 to 45.01]).

The effect of physical activity on the PSC was significant even after controlling for socioeconomic factors and pre-existing health diagnoses. However, there was no significant association between physical activity and MCS.

"Combined with existing evidence, this study contributes to growing evidence of the benefits of maintaining or adopting an active lifestyle in mid-age," the authors say.

"An important public health message is that being active for as many years as possible, even if women start to meet physical activity guidelines in their mid-50s, could have important health benefits in terms of physical health, especially in physical functioning."

The authors add, "Our study shows that it's important for women to be active throughout mid-age to gain the most benefits for physical health in later life. Ideally, women should increase their activity levels to meet the guidelines by age 55."

Funding: The Australian Longitudinal Study on Women's Health is funded by the Australian Government Department of Health. GIM is supported by a National Health and Medical Research Council Investigator Grant (APP2008702). DD is funded by an Emerging Leader Fellowship from the National Health and Medical Research Council (2009254) and an Early-Mid Career Researcher Grant under the New South Wales Cardiovascular Research Capacity Program. The funders had no role in the study design, data collection and analysis, decision to publish, or preparation of the manuscript.

About this aging, exercise, and health research news

Author: Claire Turner

Source: PLOS

Contact: Claire Turner - PLOS

Image: The image is credited to Neuroscience News

Original Research: Open access.

"Competing interests: The authors have declared that no competing interests exist" by Binh Nguyen et al. PLOS Medicine

Abstract

Competing interests: The authors have declared that no competing interests exist

Background

There is little long-term causal evidence on the effect of physical activity on health-related quality of life. This study aimed to examine the associations between longitudinal patterns of physical activity over 15 years and health-related quality of life in both the physical and mental health domains, in a cohort of middle-aged Australian women.

Methods and findings

We used data collected at 3-year intervals (1998 to 2019) from 11,336 participants in the Australian Longitudinal Study on Women's Health (ALSWH) (1946 to 1951 birth cohort).

Primary outcomes were the physical (PCS) and mental health component summary (MCS) scores (range from 0 to 100; higher scores indicate higher perceived physical/mental health) from the SF-36 in 2019 (when women aged 68 to 73 years).

Using target trial emulation to imitate a randomized controlled trial (RCT), we tested 2 interventions: (1) meeting the World Health Organization (WHO) physical activity guidelines consistently throughout the 15-year "exposure period" (2001 to 2016; when women aged 50-55 to 65-70 years; physical activity assessed every 3 years); and (2) not meeting the guidelines at the beginning of the exposure period but starting to first meet the guidelines at age 55, 60, or 65; against the control of not meeting the guidelines throughout the exposure period.

Analysis controlled for confounding using marginal structural models which were adjusted for sociodemographic and health variables and conditions. Consistent adherence to guidelines during the exposure period (PCS: 46.93 [99.5% confidence interval [CI]: 46.32, 47.54]) and first starting to meet the guidelines at age 55 (PCS: 46.96 [99.5% CI: 45.53, 48.40]) were associated with three-point higher PCS (mean score difference: 3.0 [99.5% CI: 1.8, 4.1] and 3.0 [99.5% CI:1.2, 4.8]) than consistent non-adherence (PCS: 43.90 [99.5% CI: 42.79, 45.01]).

We found a similar pattern for most SF-36 subscales but no significant effects of the interventions on MCS. The main limitations of the study were that it may not account for all underlying health conditions and/or other unmeasured or insufficiently measured confounders, the use of self-reported physical activity and that findings may not be generalizable to all mid-age women.

Conclusions

Results from the emulated RCT suggest women should be active throughout mid-age, ideally increasing activity levels to meet the guidelines by age 55, to gain the most benefits for physical health in later life.