Physiology

Menopause and Weight Lifting

Menopause is characterized by the cessation of the female menstrual cycle for a calendar year. Perimenopause is the time period around this year that can last for about 7 to 12 years. This period involves a slow decline in female hormones, most importantly, estrogen. The decrease in these hormones causes a number of different symptoms such as hot flashes, muscle loss, fatigue, mood changes, difficulty sleeping, and joint pains.

The decrease in estrogen during perimenopause and menopause also results in bone loss. Estrogen concentrations in the blood can even be used as a predictor for bone fractures. It has been well documented in research that weight-bearing exercises are a great way to improve bone density. An 8-month course of high-intensity resistance training and weight-bearing exercise improved bone density scores at all sites of the body and improved physical performance scores in menopausal women with osteopenia when compared to women who performed low-intensity home exercises.

As women get older they have more difficulty building and maintaining muscle mass. This is in part due to changes in the proportion of muscle fiber types within the muscles. Specifically, type I muscle fibers (slow contraction, more endurance-oriented fibers) are maintained while type II fibers (fast contraction, strength-oriented fibers) decrease in numbers. This change in proportions is due to reduced amounts of estrogen in the blood stream. A great way to counteract this change is by strength training. Several studies have shown that strength training can increase muscle strength in menopausal women. Improving strength and muscle mass also has the added benefit of increasing one’s metabolism since lean muscle takes more energy to maintain.

This brings me to the last benefit of weight training during perimenopause and menopause that I will touch on. The mechanism behind resistance exercise and fat loss is two-fold. Besides the obvious reason of burning calories from actually doing the exercise, resistance exercise works to increase the calories burnt at while resting – our basal metabolism. This occurs over time as you slowly increase the amount of lean muscle tissue in the body because, like other living organs in the body, muscles have their own energy demand in order to be sustained.

The effect of strength training on body composition and weight control in menopausal women has been studied by numerous groups and different methods. Longer-term approaches (>6 months) had more consistent effects but positive results were found in interventions lasting only 8-12 weeks. Higher intensity exercise was shown to have greater effectiveness at facilitating fat loss than lower intensity exercise. In many of the long-term studies, the control groups (who didn’t strength train) lost muscle tissue and gained fat mass so simply maintaining baseline level composition is also considered progress.

Perimenopausal and menopausal women often gravitate towards cardio machines for weight control and fat loss without considering the possible benefits of weight and resistance training. For maintaining lean muscle mass and bone density and increasing basal metabolic rate, high intensity resistance training should be incorporated into their weekly routine.

Here’s a great podcast called Hit Play Not Pause for more information from an exercise physiologist, Dr. Stay Sims, who also recommends including high intensity, Tabata type training followed by protein to maintain muscle, energy and performance during their menopausal years.