In his first of two articles, Dr. Carson presented evidence showing that sitting for long, uninterrupted periods has serious health risks. And he followed that with some techniques for mitigating or avoiding those risks. Here is a brief addendum to underscore both the risks and the ways to counteract too much sitting.
Troubles with Sitting – Orthopedic Health Problems attributed to too much sitting
(Mathews ’12; Ford ’12; Berkowitz; Hamilton ’07; George ‘13)
Muscle degeneration (Back problems)
- Slumped muscles go unused — tight back and weak abdominal muscles combined to cause serious back pain due to extreme lower curvature (lordosis)
- Sore back: inflexible spine movement causes soft disc dehydrated and brittle. This can lead to a herniated disc. Typically the disc between vertebrae expand and contract like a sponge soaking up fresh blood and nutrients with activity.
- Collagen hardens around supporting tendons and ligaments with extended inactivity
Tight hips: decreased hip mobility due to tight hip flexors (short and tight) limit range of motion and produce falls
Limp gluts (buttocks): hurt stability and stride
Strained neck: Craning neck forward over key board or tilting head to cradle phone
Soft bones: Weight bearing exercises cause bone to grow thicker and lack thereof causes osteoporosis
Sitting can reduce life expectancy
Standing could increase your life span. The more time on your feet strengthens the bits of DNA called telomeres (Sjogren ’14). Telomeres protect the ends of chromosomes (like the tips that keep shoelaces from fraying). Telomeres tend to get shorter and shorter until they can shorten anymore and cause cell death.
Women who spend too much time sitting around (>11 hours/d) had a 12% risk of premature death (13% more cardiovascular disease; 21% more cancer; 27% more coronary artery disease) than those who were inactive for <4 hours (Sequin ’14).
Can scheduled exercise sessions offset the negative effects of sitting?
Adults spend 50% – 70% of their waking hours sitting or approximately 8 hours per day. Sitting for extended periods of time can harm even those that exercise (Craft ’12; Wilmot ’12). The increased risk of sitting is not offset by moderate to vigorous exercise or meeting the recommended physical guidelines. Regular exercise does not reduce the risk of an otherwise sedentary life style as one remains susceptible to just as great a risk of diabetes, cardiovascular disease, obesity and premature death. Short but frequent walks or alternative activity sparks (short term episodes of movement lasting 5 – 10 minutes) can counteract the harm caused by sitting long periods.
Craft LL et al Evidence that women meeting physical activity guidelines do not sit less: An observational inclinometry study Int J Behav Nutr Phys Act (2012) 9: 122.
Ford ES and Caspersen CJ Sedentary behaviour and cardiovascular disease: a review of prospective studies Int J Epidemiol (2012) 41: 1338 – 1353.
George ES et al Chronic disease and sitting time in middle-aged Australian males: findings from the 45 and Up Study Int J Behav Nutr Phys Act (2013) 10:20.
Hamilton MT et al Role of Low Energy Expenditure and Sitting in Obesity, Metabolic Syndrome, Type 2 Diabetes, and Cardiovascular Disease Diabetes (2007) 56: 2655 – 2667.
Matthews CE et al Amount of time spent in sedentary behaviors and cause-specific mortality in US adults AJCN (2012) 95: 437 – 445.
Sjogren P et al Stand up for health–avoiding sedentary behaviour might lengthen your telomeres: secondary outcomes from a physical activity RCT in older people Br J Sports Med (2014) 48: 1407 – 1409.
Wilmot EG et al Sedentary time in adults and the association with diabetes, cardiovascular disease and death: systematic review and meta-analysis Dibaetologia (2012) 55: 2895 – 2905.