Risks of Sedentary Lifestyle

by Theresa Min

A sedentary lifestyle refers to a lifestyle of low physical activity, which includes prolonged periods of sitting, lying down and low/no exercise. These activities can be working in an office/school, using a computer/smartphone, watching television and driving and other low physical activities. This lifestyle is a global issue in various age groups as insufficient physical activity can be detrimental to health and affect different physiological processes. It is hypothesized that sedentary behavior can “decrease cardiac output and systemic blood flow while activating the sympathetic nervous system”; “elevate hormone-related cancers”; “weight gain, adiposity and elevated chronic inflammation”; which are all risk factors for cancer (Park, 2020). Low physical activities can not only affect physical health but can also negatively impact mental health. It is important to promote increased physical activities and to intervene in sedentary behaviors for all ages to decrease chronic disease.

While a sedentary lifestyle has increased over the years and become more common, the exact mechanisms of sedentary behavior are unknown but many hypotheses have been derived to best explain the impact of sedentary behavior on physiological processes. For example, physical inactivity can reduce bone mineral density. “12 weeks bed rest decreasing mineral density on the lumbar spine, femoral neck & greater trochanter (femoral neck & greater trochanter on the femur, thigh bone) by 1-4%”; emphasizing the relationship of a sedentary lifestyle and decreased health (Park, 2020). A pattern of low/no physical activity can greatly impact blood pressure as it can “alter cardiac output and total peripheral vascular resistance” by reducing “metabolic demands, systemic blood flow, insulin sensitivity and vascular function” (Park, 2020).  It is also assumed and proven from many studies that low physical activity and lack of moderate to high intensity exercises (cycling, swimming, dancing, running, weight training, etc.) can increase weight gain, a risk factor for obesity. A common way obesity occurs is excess calorie intake, physical inactivity, genetics and even psychological factors (depression, anxiety). Although weight gain can be out of people’s control as there are many environmental, social and economic factors: it is important to try to break away from a sedentary lifestyle as this is a risk factor for several types of cancers. 

Sedentary behaviour have a close relationship with cancer as a “study found that the correlation between sedentary behaviour and cancer prevalence, the cancer risk was 13% higher in the group with longer sedentary time: another study finding sedentary time increasing overall cancer risk by 20%” (Park, 2020). With prolonged sitting, it was found that “colorectal, endometrial, ovarian and prostate cancer increased”, an even higher cancer mortality in women (Park, 2020). Breast and endometrial cancers can be increased from altered levels of sex hormones. Increased sedentary behavior can lead to increased metabolic dysfunctions of “hyperglycemia ( high blood sugar), hyperinsulinemia (high insulin levels), insulin resistance, and changes in the circulating levels of sex hormones” increasing the likelihood of hormone-related cancers (Park, 2020). For mental health, it is important to note that “mentally active sedentary behaviours (, reading, driving, knitting or sewing) were NOT markedly correlated with depression”; but further research is needed on computer use (Park, 2020). However, sedentary behaviour can increase the risk for depression as it can limit social interactions and can reduce time in physical activity to prevent depression. 

Recommendations: 

1.  Take small breaks

●  Get up after a meeting 

●  Stand up when you can 

2.  Take a brisk walk outside or take the stairs when you can 

3.  Try to engage in moderate exercise (150 minutes) or vigorous exercise (75 minutes) per week.  

●  Break it up and take it easy! 

●  Exercise with friends!  

●  Activities include yoga, tennis, pickleball, swimming, etc. 

4.  Try engaging in mentally active sedentary behaviors rather than passive sedentary activities 

●  Knitting, puzzle games, reading, writing    

●  Reduce time watching TV, excess time on the phone 

References: 

Park, Jung Ha et al. “Sedentary Lifestyle: Overview of Updated Evidence of Potential Health Risks.” Korean journal of family medicine vol. 41,6 (2020): 365-373. doi:10.4082/kjfm.20.0165