Resistance training should be done by everyone, regardless of age and sex. Consistent resistance training can help attenuate symptoms of aging such as loss of bone and muscle mass, loss of brain function, and decrease in metabolic function. Exercise, including resistance training, is currently the strongest "longevity drug" available and is essential for maintaining health and performance with age.

Key Takeaways 

1. Resistance training inhibits the natural loss of bone density and muscle mass in aging populations. 
2. Resistance training has beneficial effects on the brain, leading to the growth and preservation of brain cells. It improves executive function by altering the frontal lobe. 
3. Resistance training improves blood glucose control and helps combat the natural decline in metabolic rate with age.
4. Lifting weights reduces the risk of cardiovascular disease. 

There seems to be an idea floating around that once you hit a certain age you must stop lifting weights. Generally, younger individuals tend to exclusively perform resistance training while older individuals choose aerobic, cardiovascular training. In reality, there should be no age limit to lifting weights. The benefits of resistance training have been studied across all age groups, and should be done by everyone. Let’s explore some of these benefits backed by research and shed some light on why resistance training arguably becomes even more important as you age. 

Muscle and Bone Loss with Aging 

Aging comes with many unwanted side effects. While some are unpreventable, conditions like osteoporosis (bone loss) and sarcopenia (muscle loss) can be attenuated by resistance training. 

After age 50, bone loss starts to occur in both men and women, although women are generally affected more (1). 

To stimulate the bones to produce more mass, they must be exposed to a mechanical load or force greater than that experienced during normal daily activity (2).  

While aerobic, cardiovascular training has beneficial effects for various systems in the body, it does not provide enough of a stimulus to cause bones to grow, and is inferior to resistance training as a modality to improve symptoms of bone loss (3). 

Many older individuals choose walking for exercise - which is beneficial for health, but does not optimize bone and muscle health (4). 

Sarcopenia is the age associated loss of muscle mass due to a decrease in anabolic (growth) signaling (5). 

For older adults, those over 65 years of age, resistance training 2-3 times per week is beneficial in improving muscle strength and size (6). 

A potential mechanism for why healthy aging over time leads to muscle loss might be due to gene changes that cause mitochondrial dysfunction. 

After a six month resistance training program in both healthy older and younger adults, this process of mitochondrial impairment and muscle weakness was reversed on a cellular level. Resistance training quite literally partially reverted the genetic signatures of aging back to previous levels (7). 

There truly is no age limit on weight training, as even elderly, up to 96 years of age and described as “frail” in condition, gained muscle mass, size, and functional mobility with weight training (8). 

This is important because as aging occurs, falling and fracture risk increases. 

Exercise programs that take into account stability for at least two hours a week show beneficial effects on preventing falls in older populations 65+ (9). 

The sooner you start, the better. But thankfully, science is on your side and it’s never too late to reap the benefits of resistance training on your health. 

Brain Function 

Aging not only affects muscular strength but also affects the brain in the form of reduced brain activity and structural changes. 

There is a link between the preservation of muscle mass and strength and cognitive function, as resistance training causes positive neurological changes in the brain. 

A systematic review of 18 studies concluded that resistance training across all age groups leads to significant functional changes in the brain, specifically the frontal lobe, which results in increased executive functioning (10). 

Executive function is a set of mental skills that include working memory, planning, multitasking or mental flexibility, and self-control. Trouble with executive function can lead to difficulty focusing, following directions, and handling emotions (11). 

How about if you wait until you’re older to start? In sedentary, elderly males aged 65-75, 24 weeks of resistance training at both moderate and high intensities demonstrate equal beneficial effects on cognitive functioning (12). 

Exercise can cause growth of new brain cells, increased connections between brain cells, growth of blood vessels in the brain, and increased proteins that support the survival of brain cells. 

In addition to a healthy diet and lifestyle, the addition of resistance training should be regularly implemented to preserve and increase brain function (13). 

Metabolic Function and Cardiovascular Disease Risk 

Along with age comes a natural, almost linear decline in metabolic rate. 

The reason many people gain weight as they age is they don’t factor in this natural decline and continue eating like they were young. Overconsumption of calories leads to fat accumulation, which over time can disrupt proper nutrient metabolism and lead to metabolic dysfunction (14). 

Since skeletal muscle is the organ responsible for consuming the largest amount of energy in the body, maintaining and building lean muscle mass through resistance training is crucial as you age to keep metabolic rate high and prevent weight gain. 

Blood glucose tolerance decreases with age and high blood sugar over time can lead to type 2 diabetes and a host of health problems (15).

Resistance training leads to an increase in glucose uptake from the bloodstream by increasing the quantity and function of a glucose receptor, GLUT-4. GLUT-4 is found primarily in striated muscle tissue such as skeletal muscle and the heart, and adipose (fat) tissue (16). 

It doesn’t seem to take much training to elicit this effect either. Resistance training for 30 mins 3x a week improved insulin action (insulin clears sugar from the bloodstream) in both healthy and type 2 diabetic subjects (17). 

This result was supported by numerous other studies indicating a benefit of resistance training on blood glucose control in elderly patients (average age of 66 years) with type 2 diabetes (18). 

When we think of exercise for heart health, cardiovascular or endurance exercise usually comes to mind. However, resistance training can be beneficial on heart health as well. 

An association was found between resistance training and reduced risk of CVD and all cause mortality, independent of aerobic training (19). 

This effect isn’t reserved for older populations. Resistance training twice per week in healthy, young adolescents resulted in increased vascular (blood vessel) function (20). 

When trying to optimize heart and cardiovascular function, a combination of both resistance training and endurance training seems to be best, compared to each as a standalone (21). 

Resistance training has a beneficial effect on heart health and improving symptoms of age associated metabolic decline such as decreased basal metabolic rate and blood glucose control. 

Bottom Line:

Resistance training is beneficial for people of every age and sex. Lifting weights is an important habit to preserve life quality and function with age. Consistently training 2-3x a week can afford you the ability to continue doing the things you love, with the people you love, as you age. 

Andrew Malkiel, MSc

References

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