Women, Strength Training, and Diabetes

Weight training reduces the risk of diabetes for women, and combining it with cardiovascular exercise provides even more protection

Type 2 diabetes is a major public health concern which is on the rise. Internationally, it is estimated that 346 million people have type 2 diabetes.  According to the World Health Organization, diabetes-related deaths are expected to double between 2005 and 2030. More than 80% of these deaths occur in low- and middle-income countries. In terms of prevention, aerobic exercise is known to prevent type 2 diabetes, and muscle-strengthening alone or in combination with aerobic exercise improves control of diabetic symptoms. Men who weight train have been found to have a reduced risk of developing diabetes, but whether such an association exists for women has not yet been established. Anders Grøntved (Harvard School of Public Health, Boston, and University of Southern Denmark) and colleagues prospectively followed up middle-aged and older women for 8 years from the Nurses' Health Study and Nurses' Health Study II who did not have diabetes at baseline.  They wanted to determine whether the weekly time spent performing resistance exercise, lower intensity muscular conditioning exercises (yoga, stretching, toning), and moderate to vigorous aerobic physical activity reported at baseline (2000-2001) and in 2004/2005 was associated with a reduced risk of new onset diabetes. Among the 705,869 study participants, 3491 women developed type 2 diabetes during the 8 years of follow-up. It was found that resistance exercise and lower intensity muscular conditioning exercises were both independently associated with a reduced risk of diabetes, even after adjusting for aerobic activity and other confounding factors. Women who engaged in at least 150 min per week of aerobic activity and at least 60 min per week of muscle-strengthening activities had the most substantial risk reduction compared with inactive women. Limitations to the study were that physical activity was self-reported by questionnaire, and the study population consisted of nurses with mostly European ancestry.

The authors state, "The findings from our study…suggest that incorporating muscle-strengthening and conditioning activities with aerobic activity according to the current recommendation for physical activity provides substantial benefit for [diabetes] prevention in women." While women who followed current recommendations for both muscle-strengthening and aerobic activity had a substantially reduced risk of diabetes, even those who engaged in muscle-strengthening and aerobic activity at levels lower than currently recommended saw their risk reduced. Reference: Anders Grøntved, et al. Muscle-Strengthening and Conditioning Activities and Risk of Type 2 Diabetes: A Prospective Study in Two Cohorts of US Women. PLoS Medicine, 2014; 11 (1): e1001587 DOI: 10.1371/journal.pmed.1001587 Exercise Specialist Recommendations: It is critical for women to lift weights.  Eighty percent of people over the age of 75 cannot lift 10 lb.  That is equivalent to a sack of potatoes or a newborn baby.  Maintaining functional capacity is necessary for independent living, and as most women start off with less muscle mass than men, they are at a distinct disadvantage as the normal aging process occurs. The good news is that an appropriately designed strength training program can mitigate age-related muscle loss, known as sarcopenia.  This can mean the difference between living on your own, and having to move to assisted living.  It is never too late to start!