Sit less, move more, as CV risk remains even with exercise

For individuals who sit for the most part of their day, engaging in light or moderate physical activity may be insufficient to cancel out the cardiovascular (CV) risks tied to a sedentary lifestyle, a study suggests.

“Our results indicate that an individual sitting 8.5 hrs/day on average performing at or below the current exercise recommendations could enter a moderate TC/HDL* risk category in early adulthood,” said the researchers.

In the news release, senior author Professor Chandra Reynolds from the University of Colorado Boulder, US, underlined that “taking a quick walk after work may not be enough.”

Reynolds and colleagues evaluated data from 1,327 CATSLife** participants (mean age 33.2 years, 53 percent women). They reported sitting 60.07 hrs/week or 8.58 hrs/day on average. [PLoS One 2024;19:e0308660]

Results from the linear mixed-effect model showed that individuals with greater vigorous activity had a lower TC/HDL ratio. To put it further into context, the investigators explained that individuals engaging in 30 min of vigorous exercise daily at age 35 had lower TC/HDL values equivalent to sedentary individuals 5 years younger, and those engaging in such activity at age 30 had lower BMI values equivalent to sedentary individuals 10 years younger.

Don’t ‘sit on it’

The researchers stressed that the adverse health effects from sitting are “not inescapable”. Thanks to the COVID-19 pandemic, the need to stay indoors upped the ante – the ‘couch potato’ lifestyle has become a staple for most. [Prev Med Rep 2020;20:101256; Prog Cardiovasc Dis 2022;73:61-66]

“Failing to disrupt sedentary behaviour could set a course towards poorer health and functioning across the lifespan, [as] once disease onset occurs for many chronic conditions, disease maintenance will be the primary focus of health intervention instead of recovery,” the investigators explained.

“Given these links, early intervention of suboptimal BMI and TC/HDL values is critical to prevent a multitude of health-related issues past early adulthood,” they continued.

Light/moderate movement not a guarantee

While recommendations suggest that any moderate or vigorous physical activity is better than none, evidence shows that the latter provides better CV and metabolic benefits. [J Am Coll Cardiol 2017;70:1701-1703; Int J Sport Nutr Exerc Metab 2013;23:312-321]

“[I]ncorporating more vigorous activity would be needed as sitting time increases. Our results challenge recommended physical activity, and we suggest adjusting guidelines to account for sitting time throughout the day,” said the researchers.

Nonetheless, they underlined that despite the reduced TC/HDL and BMI levels with greater vigorous activity in the study, it could not completely buffer the adverse effects of prolonged sitting.

As such, they recommended “sitting less throughout the day, getting much more vigorous exercise, or a combination of both to reduce the risk of premature ageing in early adulthood … [These are] clear messaging points to the public to provide a succinct and impactful change to sedentary habits.”

First author Ryan Bruellman, a doctoral candidate in the Department of Genetics, Genomics and Bioinformatics at the University of California Riverside, US, pointed to the relatively young study population. “Young adults tend to think they are impervious to the impacts of ageing. They figure, ‘My metabolism is great; I do not have to worry until I am in my 50s or 60s.’ But what you do during this critical time of life matters.”