The Health Risks of a Sedentary Lifestyle and How to Stay Active
U.S. adults spend an average of six to eight hours a day sitting, according to the American Heart Association, increasing their risk of serious health issues. Regular walking, a simple yet effective form of exercise, can mitigate these risks, experts say.
How Inactivity Impacts the Body
Cardiovascular decline is a major consequence of prolonged sitting. “Regular walking helps control blood pressure, blood glucose, and cholesterol,” says Amit Saini, M.D., a geriatrician at Kaiser Permanente Medical Group. Studies show that inactivity raises the risk of cardiovascular diseases, including coronary artery disease and hypertension. A 2018 analysis of the Honolulu Heart Program found that older men walking more than 1.5 miles daily had half the risk of new coronary heart disease compared to those walking less than 0.25 miles.
Without weight-bearing exercise like walking, muscle mass and strength deteriorate. Jason Snibbe, M.D., a board-certified orthopedic surgeon, notes that skeletal muscle in the legs and glutes can lose mass within days of inactivity. A 2016 study observed significant muscle atrophy in participants who reduced their daily steps to 5,000 over 14 days.
Bone density also declines with inactivity. "Walking is a weight-bearing exercise that stimulates bone remodeling," Snibbe explains.
Insulin resistance rises with prolonged sitting. A 2019 study in *Diabetes Care* found that reducing daily steps from 12,000 to 5,000 over three days led to higher post-meal glucose levels. Long-term sedentary behavior is linked to elevated fasting glucose, triglycerides, and lower HDL cholesterol, raising type 2 diabetes risk.
Cognitive function suffers as well. "Walking increases BDNF, which supports brain plasticity," says Snibbe.