Sitting for your job and your cardiovascular health

The World Health Organization guidelines recommend reducing sedentary behaviours for improved health outcomes. However, little is known about the connection with prolonged occupational sitting and cardiovascular health.

New 2024 research (Occupational sitting time, leisure physical activity, and all-cause and cardiovascular disease mortality) looked beyond just being inactive and investigated those which sat during the day for their occupation.

Participants in the ‘mostly sitting’ group tended to be younger and more educated, had fewer lifestyle risks like smoking and drinking, and were less likely to be overweight or obese, or have hypertension. However, the lower risk factors among the ‘mostly sitting’ group did not influence the higher probability of cardiovascular disease related death. There was a 34% higher risk of mortality due to CVD among the ‘mostly sitting at work’ group compared to the ‘alternating’ and ‘mostly non-sitting’ group.

The total number of participants in the study was 481,688: -    Mostly sitting – 290,075 -    Alternating sitting and non-sitting – 140,210 -    Mostly non-sitting – 51,403

The total number of CVD-related deaths was 5371. Here is a breakdown of some of the results.

Population group	CVD deaths (n)	CVD deaths (%)
All participants
Mostly sitting	3234	60.2%
Alternating sitting and non-sitting	1407	26.2%
Mostly non-sitting	730	13.6%
Men
Mostly sitting	1784	33.2%
Alternating sitting and non-sitting	703	13.1%
Mostly non-sitting	567	10.6%
Women
Mostly sitting	1450	27.0%
Alternating sitting and non-sitting	704	13.1%
Mostly non-sitting	163	3.0%
Age <60
Mostly sitting	925	17.2%
Alternating sitting and non-sitting	578	10.8%
Mostly non-sitting	305	5.7%
Never smokers
Mostly sitting	1875	35.0%
Alternating sitting and non-sitting	836	15.6%
Mostly non-sitting	281	5.2%
Without hypertension
Mostly sitting	2280	42.5%
Alternating sitting and non-sitting	936	17.4%
Mostly non-sitting	435	8.1%
Without diabetes
Mostly sitting	2449	45.6%
Alternating sitting and non-sitting	1158	21.6%
Mostly non-sitting	610	11.4%

The study included a few potential reasons or explanations which may explain the harmful effects for prolonged sitting:

• Deficient exercise of the large lower limb muscles and the truck of the body.
• Reduced blood flow to the lower extremities.
• The existence of a biomarker for low-grade inflammation.

 References

• Heart disease - Symptoms and causes - Mayo Clinic
• Occupational sitting time, leisure physical activity, and all-cause and cardiovascular disease mortality
• WHO Guidelines on physical activity and sedentary behaviour