To Your Health

Resistance Training

By Dr. Nancy DiMarco, Ph.D.

One of the major components of physical fitness is muscular strength and endurance — the others being cardiovascular endurance, body composition and muscular flexibility.

Body weight is not the best indicator of fitness. Body composition much more closely reflects fitness and is the ratio of lean tissue or muscle mass to fat tissue or adipose mass.

Resistance training is one of the most effective ways to improve overall fitness, yet only 16 percent of adults between the ages of 18 and 64 participate in resistance training at least twice a week.

WHAT IS RESISTANCE TRAINING?

Resistance training is really a stress on the body that when properly applied will cause it to adapt in a positive way. Resistance training forces the muscles to shorten (contract) against a weight (resistance) like a dumbbell or even your own weight. This causes an overloading of the muscle, which then forces it to add muscle mass and increase strength.

An increase in muscle mass is one of the best ways we can increase our metabolic rate, decrease fat and, for the most part, slow down the inevitable march of the clock. We all age but we all don't age at the same rate. Increasing lean tissue or muscle mass can help that fight, and one of the ways to have more lean tissue is to engage in regular resistance or weight training. Studies have shown that people who engage in a weight-training program can achieve the physical fitness and strength levels of persons 20-25 years younger.

Of all the types of activities possible to get involved with today, weight training truly could be viewed as the “fountain of youth.”

THE BENEFITS OF RESISTANCE TRAINING:

An increase in bone, muscle and connective tissue strength and also a decrease in the risk of injury. Improvement in posture, balance and coordination are also associated with weight training. Resistance training also increases muscle mass.

If you are over the age of 45 and not in some type of exercise program, you are losing on average 5 to 7 pounds of muscle mass per decade largely due to inactivity. That amount of muscle mass loss can make accomplishing even simple activities difficult.

Recent studies have shown that through even simple weight-training programs, muscle mass can be maintained or even increased. And it is never too late to start seeing results. A recent study completed at Tufts University enrolled a group of elderly (over the age of 70) residents in a weight-training program and after 10 weeks, all had doubled their strength and four gave up walkers for canes!

Resistance training also changes the percentage of body fat by increasing muscle mass. Muscle is the predominant tissue in the body that burns calories, so an increase in muscle mass will increase the number of calories burned at rest (basal metabolic rate or BMR). By increasing muscle mass, BMR increases and actually makes it easier to maintain body weight and should allow you to consume more calories — what a benefit!

In terms of energy expenditure, an average 130-pound woman could burn an extra 250 calories per day at rest by engaging in regular weight-training that increases muscle mass. That's equivalent to four additional pieces of fruit or an extra 2.5 pieces of bread per day.

A 200-pound man with 150 pounds of muscle or lean tissue and 50 pounds of body fat requires 2,000 calories per day. But a 200-pound man with 175 pounds of muscle or lean tissue and 25 pounds of fat needs 3,000 calories per day!

Lifting weights may be as beneficial for your heart as well as your waistline, according to the American Heart Association (AHA). Resistance training reduces the stress on the heart when lifting objects. Another AHA study showed that weight training also decreases resting blood pressure by up to 4 percent. Resistance training has also been shown to increase HDL-cholesterol (the good cholesterol) and improve insulin resistance (a condition that leads to Type II diabetes – a cardiovascular disease risk factor).

WHAT DOES A SIMPLE RESISTANCE-TRAINING PROGRAM REQUIRE?

According to an AHA advisory, a single set of 8-15 repetitions using 8-12 different exercises two to three days per week is sufficient to see strength and endurance benefits. This program can be accomplished in as little as 10 minutes a day. The weight lifting should be done as a complement to an aerobic workout, not a replacement.

And don't worry, women especially, this intensity is not going to cause you to bulk up – you would need to lift very heavy weights that would cause your muscles to fatigue after three to five repetitions plus a much more complicated routine.

Please remember to always consult a physician before beginning an exercise program.

EQUIPMENT

If you do not have access to free weights or weight machines, common things found in the home can be used. Empty detergent bottles with handles can be filled with water or sand to a desired weight (1 to 3 pounds is sufficient to begin). Even soup cans work. Small dumbbells can be purchased at most sporting goods stores. In addition, resistance tubing is very inexpensive equipment that can also provide many of the same benefits as weights. You might also consider joining a local fitness facility.

Dr. Nancy DiMarco is a research professor in the Department of Nutrition and Food Sciences, the nutrition coordinator for the Institute for Women's Health and coordinator of the master's program in Exercise and Sports Nutrition at Texas Woman's University. She can be reached at ndimarco@twu.edu.

Exercises That Can Be Done At Home

Chest press:

• Hold a weight (1 –3 pounds) or soup can in each hand, elbows bent and hands at shoulder level. Push both hands straight out until arms are parallel to the ground. Return to the starting position. Repeat 8-15 times.

Upright row:

• Hold a weight in each hand at the front of the thighs. Raise weights to the level of the armpits, with elbows slightly higher than the hands. Lower weights to the starting position. Repeat 8-15 times.

Squats:

• Position your feet about hip's width apart with toes pointed forward. Slowly bend your knees with weight over your heels as if you were going to sit in a chair — you may want to stretch you hands out in front of you to maintain balance. Do not let your knees extend beyond the view of your toes. Bend until your thighs are parallel with the floor. Return to the starting position. Repeat 8 – 15 times

Abdominal crunch

• Lie on the floor with knees bent and feet flat. Fold your arms beneath your head. Slowly raise your head and shoulders without pulling on your neck — your abdomen should feel as if it was touching your spine — making a crescent shape with your body. Return to the starting position. Repeat 15 times.

For Further Information Contact:

Roy Kron
Director of News and Information
Tel: (940) 898-3456
e-mail: rkron@twu.edu