The Impact of Sitting All Day – Part 4
In part 1, I looked at the impact of sitting on your muscles, and in part 2 generally explored the impact on the rest of your body. In part 3 I focused on the impact of sitting on your circulatory system including your heart. In this article I will explore the impact of sedentary behaviour (sitting) and the link to cancer.
So how common is cancer?
According to Cancer Research UK
- Every two minutes someone in the UK is diagnosed with cancer.
- 1 in 2 people in the UK born after 1960 will be diagnosed with some form of cancer during their lifetime.
- Breast, lung, prostate and bowel cancers together account for over half of all new cancers each year.
- Overall cancer incidence rates in Great Britain have increased by more than a third since the mid-1970s, with almost this entire rise occurring before the late 1990s.
And here is the good news is more people survive cancer than die from it now.
- 46% of men and 54% of women cancer patients diagnosed in 2010-2011 in England and Wales are predicted to survive 10 or more years.
- Cancer survival in the UK has doubled in the last 40 years.
The Link Between Cancer & Inactivity
Last year in a meta-analysis, Daniela Schmid and Michael F. Leitzmann of the University of Regensburg in Germany analyzed 43 observational studies, amounting to more than 4 million people’s answers to questions about their sitting behavior and cancer incidences. The researchers examined close to 70,000 cancer cases and found that sitting is associated with a 24% increased risk of colon cancer, a 32% increased risk of endometrial cancer, and a 21% increased risk of lung cancer.
D Schmid & MF Leitzmann, 2014, Sedentary behaviour insreases the risk of certain cancers, Journal of National Institute of Cancer, Volume 106, No 7. see http://jnci.oxfordjournals.org/content/106/7/dju206.full
The really bad news is that your can’t exercise away the harmful effects, “Adjustment for physical activity did not affect the positive association between sedentary behavior and cancer” write Schmid & Leitzmann. Even participants who achieved the daily recommended levels of physical activity were at the same risk as those who spent their day sitting.
One theory as to why this is the case, is that regular movement boosts natural antioxidants that kill cell-damaging and potentially cancer-causing free radicals, another theory is that the excess insulin encourages cell growth.
The pancreas produces insulin, a hormone that carries glucose to cells for energy. But cells in idle muscles don’t respond as readily to insulin, so the pancreas produces more and more. A 2011 study by Stephens et al found a decline in insulin response after just one day of prolonged sitting.
Stephens et al, 2001, Effects of 1 day of inactivity on insulin action in healthy men and women: interaction with energy intake, Metabolism Volume 60, No 7 pages 941 – 949. see http://www.sciencedirect.com/science/article/pii/S002604951000315X
Related Posts
Do you have tight hips? – Part 2
I know many of my clients sit at a desk for very long hours which can lead to tight hips. So in this post I want to show you how to stretch them.
How to stretch your hips
Single knee hugging Lying on your back, grab your right knee and pull it toward your chest until you feel a stretch. Hold for 20 seconds. Repeat on the left side. Bilateral knee hugging Lying on your back, grab both knees and pull them toward your chest. Hold for 20 seconds. "Cobra pose" Lie face down on the floor, hands parallel to your shoulders. Straighten your arms, lifting your upper torso off the floor. Your lower back should be arched, with your pelvis making contact with the floor. Hold for 20 seconds, then lower yourself back down Hip flexion with abduction/adduction Lying on your back, bring one knee up toward your chest. Holding your knee with both hands, roll your knee from one side to the other for 20 seconds. Repeat on the other side. External hip rotation Lying on your back, pull your right knee toward your chest. Place your right hand on the knee and your left hand on the ankle. Gently pull your right ankle in the direction of your head. Hold for 30 seconds, then repeat on your left leg. Internal hip rotation Lying face down, bend your knees 90 degrees and let your feet fall outward. Hold for 30 seconds. If after trying these stretches you are still strugling with tight hips why not book a deep tissue massage.So how does massage reduce pain? – Part 2
Previously I explained the scientific theory for "How does massage reduce muscle pain?" in the short term . But what about the long term? I would like to introduce to you the "descending pain suppression mechanism." The brain is not a passive receiver of sensory messages, but rather a centre that interprets them and makes constant adjustments accordingly. For example, everyone knows that the way you perceive pain will be influenced by whether you focus on it or think of something else instead. And it seems reasonable to suppose that evolutionary selection may have favoured those individuals who could ignore pain signals for long enough to take actions that let them escape and survive danger.
Unpleasant cutaneous sensations stimulate nuclei within the mid brain. These nuclei in turn initiate activity in the descending spinal tracts that release endogenous opiates (inhibitory neurotransmitters) within the spinal segment receiving the painful input. This diminishes the intensity of the pain transmitted to the higher centres. Sports and Deep Tissue massage techniques can reinforce a naturally occurring discomfort, causing much greater release of opiates and achieve a more profound pain suppression.
References Basbaum A, Fields H. (1978) Endogenous pain control mechanisms: review and hypothesis. Ann Neurol 4: 451-2. Watson J (1982) Pain mechanisms: a review. 3. Endogenous pain mechanisms. Australian Journal of Physiotherapy 27: 135-43
