Strength Training and Diabetes: Do Genes Make a Difference?
Insulin is responsible for shuttling glucose into muscles, so athletes with a family history of metabolic disorders may be at risk for several problems related to exercise. In a recent Journal of Strength and Conditioning Research study, investigators sought a greater understanding of how a family history of diabetes impacts strength.
Since carbohydrates are important for energy production in each cell, the energy levels experienced by people with metabolic disorders that impact glucose levels, such as diabetes, tend to be quite low. For athletes, this might negatively impact strength.
Insulin is also an anabolic hormone, meaning it promotes muscle growth. If an athlete’s response to insulin is abnormal, their ability to develop muscle could be reduced. This would make for a double whammy when it comes to strength. Both reduced energy and reduced muscle mass are performance killers.
Since those with a family history of diabetes are at risk for developing metabolic disorders, the researchers wondered if higher-risk individuals might also respond differently to exercise.
38 healthy men and women participated in this study. Eighteen of them had a family history of diabetes, while the remaining twenty did not.
They engaged in a resistance exercise program five days per week for seven weeks. The program included full body resistance circuits, core training, and plyometrics. The resistance and core workouts were brief, lasting ten to fifteen minutes, with the plyometric workout lasting forty minutes. Strength, body mass index (BMI), resting heart rate, and other markers were measured before and after the program.
The researchers estimated the function of insulin in the body by measuring the fasting blood glucose, a standard metabolic disorder test. High blood glucose would indicate a malfunction in insulin sensitivity, meaning that glucose could get into the cells. Since exercise increases the demand of glucose in the muscles, a well-functioning insulin system will yield a healthy drop in blood sugar post-exercise. The researchers thought those participants with a family history of diabetes would demonstrate a reduced drop in blood sugar.
Fasting glucose was affected similarly between the two groups, regardless of the family history of diabetes. This is great news for people concerned about metabolic disorders impacting their strength and energy levels, as it means insulin production was able to respond appropriately to the workout.
Furthermore, there was also an inverse relationship between fasting glucose after exercise and strength improvement over the course of the seven-week program. As postulated above, this indicates that a robust and well-functioning metabolic system is good for athletic advancement. The results also suggest that a person with a history of diabetes in their family but no present metabolic disorder will not be limited by their genetics.
If you have a family history of diabetes, you will be at greater risk for impaired metabolic function. However, it seems that this history alone is not as great a stimulus to the body as exercise is. Exercise regularly and maintain healthy eating habits and a good bodyweight to mitigate the risk.
1. Ryan D. Russell, et. al., “Short bouts of high-intensity resistance-style training produce similar reductions in fasting blood glucose of diabetic offspring and controls,” Journal of Strength and Conditioning Research, DOI: 10.1519/JSC.0000000000000624
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