How Strength Training Changes Your Body for Good

And type 2 diabetes, while making you less susceptible to osteoporosis and depression. Also makes you more likely to have a lower BMI and healthy eater - while slashing your risk of depression and sharpening your thinking skills.


Story at-a-glance

  • A study involving nearly 36,000 older women suggests strength-training may lower a woman’s risk of cardiovascular disease and Type 2 diabetes independent of her level of aerobic activity
  • Strength training contributes to strong bones, making you less susceptible to osteoporosis, a condition affecting 10 million Americans that results in 2 million bone fractures annually
  • Ranging from body-weight exercises, hand weights and kettlebells to resistance machines, rope climbing and strength classes — there is a strength-training program for everyone

By Dr. Mercola

If you are still laboring under the misconception that strength training is only for hard-core bodybuilders and those interested in bulking up, it's time to change your thinking and incorporate some form of weight training into your exercise routine. Doing so will transform not only your health and physique, but also your perception of what you are capable of doing physically. If you are a woman at or older than middle age, strength training is vital because it protects against osteoporosis by increasing your bone density.

It's a well proven fact working with weights ­­— whether it be your own body weight or that of a dumbbell or machine — is a beneficial exercise that will enhance your muscle tone and strengthen your bones. New evidence also suggests strength training helps reduce your body mass index (BMI) and your risk for heart disease and Type 2 diabetes.

The Benefits of Strength Training

Similar to other forms of exercise, strength training boosts your mood and helps you build endurance and stamina. In addition, strength training helps you to:1,2

  • Avoid chronic conditions: Strength training can help prevent and/or reduce the effects of chronic conditions such as arthritis, back pain, depression, heart disease and Type 2 diabetes
  • Develop strong bones: You can reducing your risk of osteoporosis, or brittle bones, by increasing your bone density through strength training
  • Enhance your quality of life: Building muscle helps to improve your ability to do everyday activities, which will help you remain independent as you age
  • Manage your weight: Strength training can help increase your metabolism and enable you to either lose or effectively maintain your weight
  • Sharpen your thinking skills: Research suggests there is a direct correlation between strength training and cognitive well-being, especially in older adults

On top of these wonderful benefits, you will very likely enjoy the transformation strength training will bring to your physical body. Over time, you will begin to see and feel improved muscle tone, which will boost your body awareness and self-esteem. Such noticeable changes will very likely make you a lifetime fan of this type of exercise. Along those lines, Sue Clark, strength coach at Chicago-based Bodysculpt Fitness, says:3

"Strength training is the only way you're going to truly be able to sculpt the physique of your personal dreams. Above and beyond the physical changes, though, a whole new persona emerges, as people start to feel really confident in their own bodies. Once I can get someone on board with strength training, they're good for life, because they're seeing results like they've never seen with cardio."

Without Strength Training, You Are at Greater Risk for Osteoporosis

While it's easy to equate strength training to stronger muscles, you may not realize strong muscles also help your body develop strong bones. Strong bones are vital to help you maintain the structural integrity of your body, as well as to prevent against osteoporosis. Brad Schoenfeld, assistant professor of exercise science at New York City's Lehman College and member of the board of directors for the National Strength and Conditioning Association, offered this insight about how strength training affects your bones:5

"Through a process known as bone remodeling, strength training stimulates the development of bone osteoblasts: cells that build bones back up. While you can achieve some of these bone benefits through aerobic exercise, especially in your lower body, resistance training is really the best way to maintain and enhance total-body bone strength."

It may surprise you to learn your body loses bone mass at the rate of about 1 percent per year after age 40 due to:5

  • Age-related changes
  • Inadequate nutrition
  • Physical inactivity

When your bones become fragile, they are increasingly susceptible to breakage and fracture, even from minor events such as bending, falling or tripping. Eight million women and 2 million men in the U.S. suffer from osteoporosis, which is thought to be responsible for some 2 million bone fractures annually.6 It's well-known that women are at greater risk for this condition because they have smaller, thinner bones than men. Experts at Harvard Medical School note:7

"Hip fractures are usually the most serious. Six out of 10 people who break a hip never fully regain their former level of independence. Even walking across a room without help may become impossible."

Beyond the risk factors common to both men and women, bone loss is often more pronounced in women who have reached or passed through menopause. The loss of estrogen after menopause may contribute to bone loss because estrogen is a hormone designed to protect bones.8

Strength Training Shown to Protect Against Diabetes and Other Diseases

A study9 published in Medicine & Science in Sports & Exercise suggests strength training may lower a woman's risk of cardiovascular disease and Type 2 diabetes. Researchers from Harvard Medical School and the National Institutes of Health followed nearly 36,000 women for 14 years through health questionnaires.

The participants, ranging from 47 to 98 years of age, self-reported their exercise levels and health status. Study results reflect the muscle-strengthening exercise they performed was directly correlated to their incidence of heart attack, stroke and Type 2 diabetes. After adjusting for other variables such as age, diet and physical activity, compared to those who did none, the women who did any strength training at all were:

  • More likely to have a lower BMI
  • More likely to maintain a healthier diet
  • Less likely to be a current smoker
  • Shown to have a 30 percent lower risk for Type 2 diabetes
  • Shown to have a 17 percent lower risk of cardiovascular disease

Notably, researchers found the addition of aerobic exercise helped drive down the risks for diabetes and heart disease even further. For example, participants who performed at least 120 minutes of aerobic exercise a week, along with some form of strength training, were shown to have a 65 percent lower risk for Type 2 diabetes than women who did neither. The study authors noted: "These data support the inclusion of muscle-strengthening exercises in physical-activity regimens for reduced risk of Type 2 diabetes and cardiovascular disease, independent of aerobic exercise."

Beat Depression With Strength Training

Previous studies have underscored the value of aerobic exercise for depression, due, in part, to the improved mood stimulated by the release of endorphins through activities such as running. While strength training may not release as many feel-good neurotransmitters, it also has been shown to be effective against depression.

"There's a different high when you make a lift or complete your program that day," says Li Faustino, a licensed clinical psychologist in New York City who treats people with depression and also lifts weights.10 One small study11 revealed 80 percent of older depressed adults experienced a significant reduction in depressive symptoms after taking up resistance training for 10 weeks.

Research12 involving depressed senior citizens reflected a 50 percent reduction in depression-related symptoms for participants who took part in high-intensity resistance training three days a week for eight weeks. The study authors noted: "High intensity progressive resistance training (PRT) is more effective than low-intensity PRT or general-practitioner care for the treatment of older depressed patients."

Kelly Coffey, a personal trainer in Northampton, Massachusetts, who began lifting weights shortly after being diagnosed with depression, suggests strength training provides a sense of empowerment related to the illness:13

"When you challenge yourself and push yourself, it's really hard not to feel pride when you're done, and pride is the opposite of that depressive, powerless feeling. You cannot help but feel proud, empowered and satisfied at the end of a good lift."

Resistance Bands Are an Inexpensive Way to Build Strength and Muscle

If you don't have access to fancy gym equipment, resistance bands can help you increase strength and build muscular endurance as part of your home-based workout program. These stretchy bands are:

  • Simple and effective for working your muscles
  • Useful for boosting your flexibility, range of motion and stamina
  • A quick means of changing up how you do traditional strength-training exercises such as arm curls or pushups
  • Inexpensive, easy to store and perfect for exercising while you are traveling

No matter which type of bands you use, be sure to start with a light level of resistance and work your way up to higher levels of resistance over time. Check out the short video below for a demonstration of nine resistance-band exercises you can easily do at home or while traveling for business or pleasure.

When It Comes to Strength Training, You Have Many Options

A wonderful aspect of strength training is the many choices and flexibility you have. For that reason, as well as the fact it can be done at home or in a gym, you're far less likely to get bored. Beyond resistance bands, other types of strength training options include:

Body-weight exercises

Body-weight exercises, which include pushups, planks and squats, are convenient and require no special equipment, location or schedule

Hand weights

Hand weights are inexpensive and portable, and you can easily fit in a few sets of bicep curls and tricep presses while you watch TV or do other sedentary activities


A kettlebell enables ballistic movements and swinging motions not possible with traditional weights; they can help you develop power in your glutes, hips and legs, as well as stability and strength for your arms, back, shoulders and wrists

Medicine balls (exercise balls)

Medicine balls, which vary in size and weight, can be thrown, caught, lifted and swung, requiring you to use a number of different muscle groups to maneuver them

Resistance machines at your fitness center or gym

If you have access to a fitness center or gym, you may want to experiment with some good-quality resistance equipment because it will allow you to focus your mind on the effort versus the mechanics of each movement

Rope or rock-wall climbing

Climbing — a staple exercise of combat fitness and military training for millennia — targets your abs, arms, back, hands and shoulders, helping you increase agility and gain coordination

Strength classes at your fitness center or gym

Fitness centers and gyms offer a variety of strength-training classes, such as BOSU ball, Forza, Pilates, Smart Bells, Urban Rebounding, water-based exercise and yoga, and you may want to try a few of them to determine the best fit

Important Cautions if You Are New to Strength Training

Before you get started, I advise you to take a moment to evaluate your level of readiness for strength training by considering some important cautions. Check with your doctor first if you:

  • Are a senior citizen who previously has not been physically active 
  • Are currently dealing with a serious illness
  • Have a chronic condition, such as low-back pain or a bad knee

It's best to warm up your muscles before launching into strength training because cold muscles are more prone to injury than warm ones. Five to 10 minutes of brisk walking or another aerobic activity can help warm your muscles. As you do each set of repetitions, listen to your body. If you experience pain, stop the exercise immediately. You might try again by changing your posture or position or using less weight.

Using proper technique is an important aspect of strength training. Not only will good technique help you avoid injuries, but it will also ensure you achieve maximum benefits from the workout. Another technique you can try is blood flow restriction training or Kaatsu training. It involves performing strength training exercises while restricting venous blood flow (but not arterial flow) to the extremity being worked.

A significant benefit of the method is that you can do strength exercises using just 30 to 50 percent of the weight you'd normally use while still reaping maximum benefits. By restricting blood flow to the muscle, lactic acid and other waste products build up, giving you the same benefit as heavy lifting but without the dangers associated with heavy weights. For this reason, it's a great strategy for the elderly and those who are recuperating from an injury.

If you are brand-new to weight training and feel unsure about how to approach it, take a class or watch a video. Another option is to work with a personal trainer to learn the correct form and technique for the types of strength training of interest to you.

When It Comes to Exercise, Seek Variety

To achieve the biggest, lasting gains, I recommend you engage in a variety of exercise. This is important because your body adapts very quickly to any exercise routine you undertake. As such, you need to continually change up your activities to ensure your body remains sufficiently challenged.

If you are new to exercise, you may want to begin by establishing a goal to take at least 10,000 steps a day, which is around 5 miles, or 8 kilometers. In time, you'll want to advance toward 15,000 steps a day.  Once you succeed in getting more movement into your life, you will want to add other activities. Some of my personal favorites are: