Another argument for the benefits of regular exercise for people of all ages is a study published in the September 2011 issue of the Journal of Clinical Endocrinology & Metabolism.
With worldwide levels of obesity growing in all developed countries and many developing ones, the incidence of T2 diabetes is also expected to rise dramatically, impacting on people’s health and longevity, as well as creating massive health costs.
While low muscle mass has been known for some years to be connected with insulin resistance, until now no study has been carried out to test whether increasing someone’s muscle mass to average or above average levels would lead to improved blood glucose management.
Researchers at the University of California, Los Angeles (UCLA) decided to test the idea that improving muscle mass would improve a person’s diabetic health.
Fitness and Muscle as Important as Weight Loss in Diabetic Health
“Our findings represent a departure from the usual focus of clinicians, and their patients, on just losing weight to improve metabolic health,” said the study’s senior author, Dr Preethi Srikanthan. “Instead, this research suggests a role for maintaining fitness and building muscle.”
Dr Srikanthan and Dr Arun Karlamangla went through all the data from the Third National Health and Nutrition Examination Survey (NHANES III), a six year survey of over 33,000 Americans from 2-month-old babies to seniors over 75 years, to get a snapshot of the nation’s health.
Among the 30 topics investigated in NHANES III were high blood pressure, high blood cholesterol, obesity, passive smoking, lung disease, osteoporosis, HIV, hepatitis, Helicobacter pylori, immunization status, diabetes, allergies, growth and development, blood lead, anaemia, food sufficiency, dietary intake (including fats and antioxidants), and nutritional blood measures.
Improving Muscle Mass Improves Diabetic Health
Drs Srikanthan and Karlamangla looked at a nationally representative sample of 13,644 adults aged over 20, who were not pregnant and who weighed a minimum of 35 kg. The researchers focused the association of skeletal muscle mass with insulin resistance and blood glucose metabolism disorders in these individuals, comparing the measured homeostasis model assessment of insulin resistance, blood glycosylated haemoglobin levels, the prevalence of transitional/pre-diabetes mellitus (PDM), and the actual prevalence of overt diabetes mellitus
“Across the full range, higher muscle mass (relative to body size) is associated with better insulin sensitivity and lower risk of PDM,” they concluded in the article outlining their study.
Study Shows High Muscle Mass Reduces T2 Diabetes Risk
Dr Srikanthan said the study demonstrated that higher muscle mass is associated with better insulin sensitivity and lower risk of PDM or actual diabetes. “This research suggests a role for maintaining fitness and building muscle. This is a welcome message for many overweight patients who experience difficulty in achieving weight loss, as any effort to get moving and keep fit should be seen as laudable and contributing to metabolic change.”
He also suggested that BMI (body mass index) measurements were not sufficient on their own to predict who might be at risk of developing insulin resistance or T2 diabetes. “Our research shows that beyond monitoring changes in waist circumference or BMI, we should also be monitoring muscle mass,” he said.
There was also a need for further research into the connection between regular exercise, the types of exercise done, and any reduced risk of insulin resistance or diabetes, he said. “Further research is needed to determine the nature and duration of exercise interventions required to improve insulin sensitivity and glucose metabolism in at-risk individuals.”
The article, “Relative muscle mass is inversely associated with insulin resistance and pre-diabetes. Findings from The Third National Health and Nutrition Examination Survey,” appears in the September 2011 issue of JCEM.
You might also be interested to read Diet and Exercise Can Reduce T2 Diabetes Risk.