The Sao Paulo’s Medical School study authors suggest that their findings were particularly significant for women; women with weak appendicular muscles were 63 times more likely to die compared to 11.4 times more likely for a man.
Bone density and body composition was measured in 839 men and women over the age of 65, evaluating appendicular muscles to predict the longevity of the participants. The researchers suggest that this would be effective because this group of muscles moves the appendages and extremities, and plays a key role in stabilizing the hips and shoulders.
“We evaluated the body composition of this group, focusing on appendicular muscle mass, subcutaneous fat and visceral fat. We then sought to determine which of these factors could predict mortality in the ensuing years. We concluded that the key factor was the amount of appendicular lean mass,” says principal investigator Rosa Maria Rodrigues Pereira, Full Professor and Head of Rheumatology at the university, in a release.
Body composition for the 323 men and 516 women was recorded using dual energy Xray absorptiometry, revealing in all that the rate of low muscle mass was at about 20% for both genders. Blood samples were also analyzed and the participants filled out questionnaires to evaluate diet, physical activity, alcohol consumption, smoking, and whether or not they had any chronic diseases such as diabetes.
Over the 4 years study period close to 16% of the participants died, 43% due to cardiovascular problems and the mortality rate during the study was 20% for men and 13% for women. Those who passed on during the study were older than the other participants, they exercised less, and had a higher prevalence of diabetes and cardiovascular problems. Additionally women who died during the study had a lower BMI while the men were more likely to suffer from falls.
Having a lower muscle mass had the strongest link to risk of death for women, and visceral fat played a greater role for men with each 6 squared centimeter in abdominal fat doubling the risk of death, while subcutaneous fat appeared to have a protective effect in men.
After the age of 40 muscle mass loss begins to naturally occur which begins to accelerate after reaching the age 50 with most people losing between 1-2% of their muscle mass each year. This loss of muscle mass is accelerated by sedentary lifestyle habits, a protein poor diet, hospitalization, and chronic diseases. Age related sarcopenia is thought to be preventable and even reversible with increased physical exercise especially when combined with proper nutrition paying attention to protein ingestion.
