Summary: A new study suggests that regular aerobic exercise, even less than the recommended 150 minutes per week, can significantly reduce the risk of death from flu or pneumonia.
However, the benefits seem to level off or even become detrimental beyond a certain level of activity, especially in muscle-strengthening exercises. The study assessed responses from more than 577,000 adults who participated in the US National Health Interview Survey (NHIS) from 1998 to 2018.
Research has found that those who meet both aerobic activity and muscle-building goals have nearly half the risk of dying from the flu or pneumonia compared to those who don’t meet either goal.
Highlights:
- According to the research, reaching the weekly aerobic activity goal was associated with a 36% lower risk of dying from the flu or pneumonia.
- Regular aerobic exercise, even less than the recommended 150 minutes per week, is associated with a significantly lower risk of death from influenza or pneumonia.
- While reaching the weekly goal of 2 strength training sessions was associated with a 47% lower risk of death, seven or more sessions were linked to a 41% higher risk.
Source: BMJ
According to a US study published online in the British Journal of Sports Medicine.
But there may be a level above which the effects plateau or, in the case of muscle-building activities, become potentially harmful, the results suggest.
Adults are advised to do at least 150 minutes/week of moderate-intensity or 75 minutes of vigorous-intensity, aerobic physical activity, or an equivalent combination, plus at least two moderate-intensity or higher-intensity muscle-strengthening activities times per week.
Aerobic exercise, which includes brisk/brisk walking, swimming, running, and stair climbing, is sustained, increasing heart rate and causing sweating. Muscle-strengthening activities include the use of weights and resistance bands; exercises such as squats, lunges and push-ups (calisthenics); and intensive gardening.
As well as helping to maintain good health and prevent serious illness, regular physical activity may also protect against death from flu or pneumonia, evidence suggests.
The researchers therefore wanted to know if specific types and amounts of physical activity could be associated with this reduced risk.
They relied on responses from 577,909 adults who took part in the US National Health Survey (NHIS) between 1998 and 2018.
Respondents were asked how often they spent 10 minutes or more in vigorous-intensity and light- or moderate-intensity aerobic activity. And they were asked how often they did muscle-strengthening activities.
Each person was then ranked according to their ability to meet the recommended weekly goals for aerobic activity + muscle building: not meeting either; achieve the aerobic activity goal; achieve the goal of building muscle; and achieve both goals.
Five levels of physical activity were defined: less than 10, 10–149, 150–300, 301–600 and more than 600 min/week of moderate to vigorous physical activity; and less than 2, 2, 3, 4–6 and 7 or more sessions/week of muscle-strengthening activities.
Half of the respondents (50.5%) did not achieve any of the weekly goals. Their effectiveness differed significantly depending on socio-demographic and lifestyle factors, underlying health conditions, and whether they had been vaccinated against influenza and/or pneumonia.
One-third (34%) were aerobically inactive and more than three-quarters (78%) reported less than 2 weekly sessions of muscle-strengthening activities.
During an average follow-up period of 9 years, 81,431 participants died; 1,516 of those deaths were attributed to influenza and pneumonia.
Those who met both recommended weekly physical activity goals had nearly half (48%) the risk of dying from influenza or pneumonia than their peers who met neither, after taking into account potentially influencing factors.
Reaching the aerobic activity goal alone was associated with a 36% lower risk, after controlling for potentially influencing factors, while reaching the muscle building goal alone was not associated with any significant difference in risk.
In terms of quantity, performing 10–149, 150–300, and 301–600 minutes/week of aerobic physical activity was associated with 21%, 41%, and 50% lower risk, respectively, compared to to anyone. But no additional benefit was seen above 600 weekly minutes.
“Although (10-150 minutes/week) is often referred to as ‘insufficient’ because it is less than the recommended duration, it may confer health benefits over physical inactivity,” the researchers suggest. .
For muscle-strengthening activities, compared to less than 2 weekly sessions, reaching the weekly goal of 2 was associated with a 47% lower risk, but 7 or more sessions were associated with a 41% higher risk .
“Although outside the scope of this study, plausible explanations (for this dichotomy) range from inaccurate responses (such as reporting occupational physical activity, which may not confer the same protective effect as physical activity during leisure) to hemodynamic ramifications -intensity (muscle-building activity),” the researchers explain.
This is an observational study and as such cannot establish a cause, to which the researchers acknowledge various limitations.
For example, the study relied on personal recall and at a given time; the NHIS survey only captured leisure-time physical activity in bursts of 10 minutes or more, and also did not distinguish between light and moderate intensity activities.
Nevertheless, the researchers conclude, “Efforts to reduce mortality from influenza and pneumonia in adults could focus on decreasing the prevalence of aerobic inactivity and increasing the prevalence of performing 2 episodes/week of muscle building activity.”
About this exercise and health research news
Author: Caroline White
Source: BMJ
Contact: Caroline White – BMJ
Picture: Image is credited to Neuroscience News
Original research: Free access.
“Leisure-time physical activity and mortality from influenza and pneumonia: a cohort study of 577,909 American adults” by Bryant J Webber et al. British Journal of Sports Medicine
Abstract
Physical activity during leisure time and mortality from influenza and pneumonia: a cohort study of 577,909 American adults
Objective
To examine the association between leisure-time physical activity and mortality from influenza and pneumonia.
Methods
A nationally representative sample of U.S. adults (≥18 years of age) who participated in the National Health Survey from 1998 to 2018 were followed for mortality through 2019. Participants were ranked as meeting both physical activity guidelines if they reported ≥ 150 min/week of equivalent moderate-intensity aerobic physical activity and ≥ 2 episodes/week of muscle-strengthening activity. Participants were also categorized into five categories based on self-reported volume of aerobic and muscle-building activity. Influenza and pneumonia mortality was defined as having an underlying cause of death with an International Classification of Diseases, 10th Revision code from D09 to D18 recorded in the National Death Index. Mortality risk was assessed using Cox proportional hazards, adjusting for sociodemographic and lifestyle factors, health conditions, and influenza and pneumococcal vaccination status. The data was analyzed in 2022.
Results
Among 577,909 participants followed for a median of 9.23 years, 1,516 deaths from influenza and pneumonia were recorded. Compared with participants who met neither guideline, those who met both guidelines had a 48% lower adjusted risk of mortality from influenza and pneumonia. Compared to no aerobic activity, 10 to 149, 150 to 300, 301 to 600, and >600 min/week were associated with a lower risk (by 21%, 41%, 50%, and 41%). Compared with < 2 episodes/week of muscle-strengthening activity, 2 episodes/week was associated with a 47% lower risk and ≥ 7 episodes/week with a 41% higher risk.
conclusion
Aerobic physical activity, even at amounts below the recommended level, may be associated with lower mortality from influenza and pneumonia, while muscle-strengthening activity demonstrated a J-shaped relationship.