Athletic performance and vanity aside, there are many important reasons to build muscle. Not the least being the highly underestimated role of muscle in healthy aging.

As adults, with every passing decade we lose the ability to preserve muscle mass. An ever-increasing amount of research suggests that this age-related decline in muscle mass underlies many of the undesirable conditions that we associate with “getting old”, such as osteoporosis, diabetes, cardiovascular disease, unwanted weight gain, an increased susceptibility to illness and fall-related injuries. The economic burden this phenomenon places on our healthcare system is enormous; costs are estimated to be in the billions of dollars every year.

For instance, the average adult can expect to gain approximately half a kilogram of body fat every year from 30 to 60 years of age, and lose around 0.25kgs of muscle mass over that same time span. That’s approximately a 7kg loss of muscle and a 15kg gain in body fat! These age-related changes in body composition have serious metabolic repercussions.

Muscle tissue is the primary site of ATP (energy) turnover and therefore, the prime determinant of metabolic rate (which for most of us is the largest single contributor to daily energy expenditure). Muscle tissue is not only important for maintenance of a healthy weight by virtue of its mass and mitochondrial content; it is also the largest site of lipid oxidation and glucose disposal.

This means that muscle not only plays an integral role in fat and carbohydrate metabolism but also the maintenance of healthy blood glucose and triglyceride profiles that reduce the risk of cardiovascular disease and type-2 diabetes. These two conditions alone account for over 75% of all premature deaths in this country.

Over their lifespan, the average adult will lose 7kgs of muscle and gain 15kgs of body fat!

Your muscles and your immune system are intimately related. Muscle is the main reservoir and synthesis site of proteins (amino acids) that are constantly exported to meet an array of physiological demands. Muscle provides the fuel that powers all immune function and cell turnover. Without continuous synthesis within muscle, the body would run out of fuel in less than 7 hours.

For this reason, the preservation of muscle mass is critically important to populations living with conditions that promote muscle wasting such as HIV and various forms of cancer. A decline in muscle mass signals a progression in the illness but also underlines mortality.

Despite significant advances in the medication strategies used to combat these illnesses, muscle wasting is still a major problem that has not been resolved.

Disturbingly, this muscle-wasting phenomenon is prevalent in apparently healthy older adults….

Approximately 45% of “healthy” adults 65 years or older exhibit dramatic muscle loss that is similar to those with clinical illness.

There is a clear relationship between a quantitative loss of muscle and diminished functional capacity. Cross-sectional studies on older adults suggest that an age-related decline in strength is not gradual (linear); the process actually accelerates with age. Without resistance training exercise, by the time a person reaches 40 years of age they will have lost 50% of the strength they possessed in their 20s.

By the age of 60, this decline in strength will be as high as 70%. Losing functional strength means the loss of independence and quality of life; the ability to do the things you love to do.

A major problem is that the minimal amount of muscle mass required to maintain health and independent living with advancing age is unknown. Therefore, experts in this field recommend that tomorrow’s older adults should be concerned with building a greater “starting reserve capacity” today to ensure they avoid the unknown threshold that precedes physical frailty and compromised health.

By the time a person reaches 40 years of age they will have lost 50% of the strength they possessed in their 20s. By 60, this decline will be as high as 70%.

Clearly, the older you get, the more important muscle becomes! Remember, none of us are getting any younger!

To find out more about why Muscle mass matters also check out the following links:


alcohol and muscle



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