A largely inactive lifestyle may pose a greater threat to long-term health than smoking, and some experts believe today’s exercise advice may not be pushing people far enough.
Research suggests that very poor cardiovascular fitness is linked to a fourfold increase in the risk of death when compared with a highly fit lifestyle. Low muscular strength is also a major warning sign, more than doubling that risk.
By comparison, smoking increases the risk by roughly half as much. Even so, combustible cigarettes remain widely used, with about 28 million Americans still smoking.
The dangers of prolonged inactivity build quietly over time. A sedentary routine can harm the heart, weaken muscles and interfere with the body’s ability to regulate sugar and fat, raising the likelihood of heart disease, stroke, diabetes and some cancers.
Current CDC and federal recommendations for most healthy adults call for 150 to 300 minutes of moderate-intensity exercise each week, or 75 to 150 minutes of vigorous activity, along with muscle-strengthening exercises on at least two days per week.
Yet only around 20 percent of American adults meet those targets. Dr Chris MacDonald, a behavioral scientist at the University of Cambridge and author of a new report on the health consequences of inactivity, argues that the guidelines may still fall short of what people need to live healthier lives.
According to MacDonald, the current standards are framed around a “bare minimum” approach — enough to avoid clear deficiency, but not necessarily enough to help people thrive.
Poor cardiovascular fitness can quadruple the risk of death, while smoking raises it by roughly half that amount. About 28 million Americans still smoke combustible cigarettes (stock)
In his report published in the journal Frontiers in Nutrition, MacDonald cited a study that tracked over 122,000 adults for more than eight years. It found that low muscular strength is linked to roughly a 200 percent higher risk of early death compared to high strength.
Very low cardiovascular fitness is associated with about a 400 percent higher risk.
Researchers behind that report looked at patients who underwent exercise treadmill testing and grouped them by fitness level: low, below average, above average, high and elite.
People in the elite fitness group had about 80 percent lower risk of death compared to those in the lowest fitness group.
Being unfit carried a risk of death comparable to or even greater than having coronary artery disease, smoking, or diabetes. In fact, the increased mortality risk associated with low fitness was several times larger than the risk tied to smoking.
Smoking, a separate study found, raises mortality by about 50 percent by comparison. The statistic that MacDonald cited came from a 2017 meta-analysis of 12 studies regarding the risk of sudden death due to smoking.
The report found that current smokers have more than three times the risk of sudden cardiac death compared to never-smokers. Former smokers still carry an elevated risk — about 38 percent higher than never-smokers — but quitting lowers it.
Each additional 10 cigarettes per day raises the risk of sudden cardiac death by about 58 percent, according to the report.
Over 122,000 adults were tracked for more than eight years in a 2018 study. The least fit had roughly five times the death risk of the most fit, which is a 400 percent higher risk
The study’s authors noted that because 80 percent of sudden cardiac deaths are caused by heart rhythm disturbances, smoking’s link to arrhythmias through nicotine’s effects on the heart’s electrical system may help explain the connection.
MacDonald did not specify the health risks tied to vaping. The statistic he cited referred to traditional cigarettes.
The harms of a sedentary lifestyle are also well-documented.
In one study of older adults, those who were physically inactive had more than double the mortality risk of their more active peers.
When physical inactivity is combined with other risk factors like smoking or obesity, the effects compound dramatically.
Adults who are inactive, smoke, and are obese face a mortality risk more than 230 percent higher than those without these risk factors.
Low fitness is associated with a two- to 2.5-fold increase in mortality risk regardless of body weight. This relationship holds across decades of follow-up, with low fitness consistently linked to higher death rates in both men and women.
The CDC recommends 30 minutes of moderate exercise daily, five days a week plus strength training twice weekly. Only 20 percent of Americans meet these goals (stock)
Muscular strength matters just as much. Low muscular strength is independently associated with higher all-cause mortality, even after accounting for physical activity levels and cardiorespiratory fitness.
Referring to the UK’s single-payer National Health Service’s recommendation to aim for at least 20 minutes of moderate exercise a day, MacDonald said guidelines are framed around ‘minimums’ that ‘are not supported by the best available data nor do they explain the broader benefits.’
‘The UK and other governments should be ambitious and aspire to have the healthiest populations possible. Limiting recommendations to casual strolling and encouraging people to sit less, and reducing success to the number of daily steps is unambitious and inadequate,’ MacDonald said.
‘In my opinion, we should instead promote a culture that values strength, fitness, and purposeful movement across the lifespan, enabling people not merely to live longer, but to remain capable, independent, and vibrant throughout their lives.’
