Mild cognitive impairment (MCI) is a condition where a person has minor problems with things like memory, thinking, attention, language or visual depth perception. The problems are usually not severe enough to affect activities of daily living. But some people with MCI go on to develop dementia – Alzheimer’s in particular. A new study published in the Journal of the American Geriatrics Society by Mavros et al from the University of Sydney has looked into the effects of strength training on cognitive function. The researchers selected 100 people with MCI aged 55 or over. Part of the subjects were put through progressive resistance training (PRT) 2x/week for 6 months. Unsurprisingly, the resistance training led to increases in strength but interestingly the strength increases were linked to improvements in mental ability. The researchers conclude that the link between strength gains and cognitive function merits further study.
New research by Romani et al. from The John Hopkins University in Baltimore has been published in The Knee and has shown that testosterone levels can have an impact on the strength of the anterior cruciate ligament (ACL). Romani’s previous research has shown that estrogen could reduce ACL strength.
The most recent study was performed on male rats. The ACLs of normal rats were compared to those of castrated rats. The testosterone levels in the castrated rats was close to zero. The researchers concluded that “rats with normal circulating testosterone had higher ACL load-to-failure and ultimate stress, indicating that testosterone may influence ACL strength and the injury rate of the ligament“. The results suggest that testosterone may help to strengthen the ACL. If coupled with the findings that estrogen could weaken the ACL, we can start to understand some of the reasons behind the differences in prevalence of ACL injuries between the sexes. Obviously, this only holds if these findings are the same in humans as well. It would also be interesting to know if these findings apply to other ligaments.
“We are but visitors on this planet. We are here for ninety or one hundred years at the very most. During that period, we must try to do something good, something useful with our lives. If you contribute to other people’s happiness, you will find the true goal, the true meaning of life.”
Dalai Lama XIV
It’s been known for a while that smoking decreases blood flow and hence reduces the transport of oxygen and other nutrients to tissues. But recent research by Ava Hosseinzadeh et al from the University of Umea in Sweden has looked into its effects on inflammation. Their findings were published in the Journal of Leucocyte Biology. They found that nicotine induces neutrophils to release neutrophil extracellular traps (NETs). NETs surround and destroy microbial pathogens but they can also lead to excessive inflammation and tissue damage. Obviously, it’s the excessive inflammation and tissue damage that’s of concern and it provides yet another reason to stop smoking.
A group of researchers led by Per Ladenvall (University of Gothenburg in Sweden) have looked into the relationship between physical capacity and health. They studied 800 middle-aged men over a period of 45 years. Physical fitness was measured by VO2 max. The results showed that low physical fitness is a greater risk of death than high blood pressure or cholesterol. It was second only to smoking as a risk of death.
Several studies have linked prolonged sitting with increased risk of mortality. A meta-analysis of data from over a million people was recently conducted by Ekeland et al. They wanted to find out if physical activity could attenuate, or even eliminate, the detrimental association of sitting time with mortality. They found that “high levels of moderate intensity physical activity (about 60–75 min/day) seem to eliminate the increased risk of death associated with high sitting time. However, this high activity level attenuates, but does not eliminate the increased risk associated with high TV-viewing time”.
Once again, the benefits of physical activity and physical fitness are clear. It’s up to us to make it a priority to move more, whether it’s through structured exercise or simply through the activities of daily living.
Vilma Aho et al from the University of Helsinki conducted 2 studies looking into the effects of sleep deprivation. The first study was experimental and consisted of partial sleep restriction to a small group of subjects. The second was an epidemiological study with over 2700 individuals. Blood samples were analysed in both cases.
The analyses revealed decreased circulating High Density Lipoproteins (HDL cholesterol), otherwise known as ‘good cholesterol’, and elevated inflammatory markers. Sleep loss decreased the expression of genes encoding cholesterol transporters and increased expression in pathways involved in inflammatory responses. The findings help to explain why sleep deprivation is a risk factor for cardiometabolic disease.
There are a couple of shoulder conditions that can be extremely painful. One is adhesive capsulitis, better known as frozen shoulder, and the other is calcific tendinitis. Calcific tendinitis is characterised by the formation of calcium deposits in the rotator cuff tendons of the shoulder. A few months ago Hackett et al from the University of New South Wales published the results of a study that could explain why calcific tendinitis is so painful. Their findings are published in The Journal of Bone & Joint Surgery.
They concluded that there was “a significant increase in neovascularization and neoinnervation in calcific tendinitis lesions of the shoulder along with an eightfold increase in mast cells and macrophages. The findings are consistent with the hypothesis that, in calcific tendinitis, the calcific material is inducing a vigorous inflammatory response within the tendon with formation of new blood vessels and nerves”.
“When touched with a feeling of pain, the uninstructed run-of-the-mill person sorrows, grieves, and laments, beats his breast, becomes distraught. So he feels two pains, physical and mental. Just as if they were to shoot a man with an arrow and, right afterward, were to shoot him with another one, so that he would feel the pains of two arrows.”
Renaud Massart et al from McGill University have recently published an article in Scientific Reports on the effects of chronic pain on the body. “Chronic pain” is pain that has lasted for 6 months or more. The study was performed on rats with induced nerve injuries.
The results showed epigenetic changes in the DNA of the prefrontal cortex and in the DNA of T cells. Their findings support the notion that persistent pain affects multiple biological systems. It’s possible that future research will show changes to other systems as well.
Would you like to live longer? Of course! I can remember as a child having what could initially appear as a morbid fascination for cemeteries. I used to drag my parents into each and every cemetery we walked or drove by…just so I could calculate how long people had lived! Perhaps my curiosity in longevity led to an interest (some may say obsession) in health.
Having just read “The Blue Zones” by Dan Buettner, I’d like to share some of his insights. Blue zones represent regions of our planet where people generally live significantly longer. For years, Buettner and his collaborators have searched the globe for those treasured blue zones in the hope of learning how to improve our health and increase our longevity.
So far, five blue zones have been identified: the mountainous regions of Sardinia, the island of Okinawa in Japan, Loma Linda in California, the Nicoyan peninsula in Costa Rica and the island of Ikaria in Greece. The first striking characteristic is that these regions are isolated by geography, culture or religion. This seems to be crucial because it means the people living in these regions have been able to continue living a traditional lifestyle until very recently. Most have grown up leading physically active lives and eating mainly plant-based diets (due to the cost of meat). Family and socialising is central to their lives. Although a lot have lived through hardships, they lead relatively stress-free lives primarily because they place little importance on money, material possessions, job status, etc.
Buettner has identified common factors that are associated with longevity and distilled them down to 9 lessons. He stresses that these practices are only associated to longevity but don’t necessarily increase it. As we know association isn’t the same as causation. The 9 lessons are:
- Move naturally. Walk, cycle, garden, enrol in enjoyable classes
- Eat until you’re 80% full. Don’t stuff yourself
- Plant-based diet. Avoid meat and processed foods
- Alcohol (in moderation)
- Purpose. Have a reason to get out of bed in the morning
- Downshift. Take time to relieve stress
- Belong. Participate in spiritual community
- Loved Ones First. Make family a priority
- Right Tribe. Be surrounded by those who share Blue Zone values
He recommends introducing one or two of them at a time. It may be easier to start with the lessons we have a greater affinity for or simply those we find easiest to adopt. It’s not even necessary to try to follow all the steps. There you go…no rocket science or witchcraft required!