Biomarkers of Aging: Blood Pressure and Insulin Reaction
Live Like You Can
By Janis McDonald
We will continue our journey through the research of William Evans, PhD and Dr. Irwin Rosenberg. Their startling 1992 studies of men in their 90’s and intense strength training changed the fitness world. I will address how strength training can positively impact blood pressure and insulin reaction, our next two biomarkers of aging.
Dr. Evans states, “My book, Biomarkers: The 10 Keys to Prolonging Vitality, is based on my hypothesis that these 10 biological markers that have been thought to occur as a result of chronological age are, in fact a product of how we live our lives. These biomarkers include muscle mass, strength, resting metabolic rate, aerobic capacity, blood pressure, insulin action, HDL to total cholesterol ratio, bone density, body fat percentage, and ability to control body temperature.” The study strongly supported the idea of the first two biomarkers (strength and muscle mass) as being the critical foundations for the remaining ones.
The increase in resting blood pressure is referred to as hypertension. Hypertension is a major risk factor for heart disease, which increases throughout the aging process. By age 60 to 70, approximately 50 percent of men and women are hypertensive, and this remains a risk factor for heart disease until a person is over the age of 85.
While studies regarding the effects of strength training on hypertension are mixed and require more research, many of the tests have resulted in lowering post-exercise blood pressure. One 12-week study of resistance training (three sets/12 reps) resulted in decreased blood pressure in middle-aged hypertensive men. While more studies are needed to discover if low reps/high weight would also be beneficial to lowering blood pressure, these results showed that weight training can decrease blood pressure in middle- aged men enough to decrease risk of heart disease and stroke by nearly half.
Increases in muscle lead to an overall favorable shift in body composition. An increase in fat mass, specifically in the abdominal region, is thought to be the first step in events that lead to hypertension, glucose intolerance, insulin resistance, and abnormal lipoprotein-lipid profiles. These are concurring risk factors are often referred to as “metabolic syndrome.”
Strength training improves body composition (percentage of fat to lean mass) in both men and women, even when calories were not controlled. Especially important is the reduction of visceral fat tissue around the abdominal area.
A loss of muscle and an increase in fat is associated with aging. The loss of muscle results in a reduction of resting metabolic rate, which can lead to obesity. Previous studies have shown heavy strength training increases muscle and resting metabolic rate in the elderly as well as improving functional ability of the body as it ages.
In conclusion, although these two biomarkers of aging are being studied for further proof, it is clear that strength training will impact blood pressure and metabolic syndrome positively as we age.
Stay tuned as the Live Like You Can column next explores muscle mass and strength training as they apply to our next two biomarkers, bone density and ratio of good cholesterol to overall cholesterol levels.
Janis McDonald, Professional Wellness Coach, Designing Your Third Act Workshops, Private Training Gym, 152 0457. Follow the Live Like You Can Blog! Go to: www.livelikeyoucan.com