As we age, our blood-carrying arteries get harder. Our muscles, on the other hand, don’t. Neither is good.
Hardened arteries are an underlying cause of several heart problems. One of those problems, high blood pressure, afflicts up to 70 percent of older Americans.
Also with aging, muscles and bones weaken, increasing chances of falling and breaking a bone. About 17 percent of post-menopausal women have osteoporosis and up to 30 percent older than 65 have it. Weight training is recommended to maintain muscle mass and bone density.
Professor Hirofumi Tanaka wants to pump up the body of knowledge about weight training’s impact on aging arteries.
Hirofumi Tanaka, a researcher at The University of Texas at Austin, wants to see if keeping our muscles toned by pumping iron will help keep our arteries supple and pumping blood.
Tanaka, director of the Cardiovascular Aging Research Laboratory in the Department of Kinesiology and Health Education, is embarking on a five-year study to determine the impact weight training has on the arteries of middle-aged and older people. The study is funded with $1.2 million from the National Institutes of Health.
Tanaka says previous weight-training studies have focused on the “Arnold Schwarzenegger-type physiques” and muscle development, but not on the impact on the cardiovascular system.
“When you think about the effect of weight training on the function of the arteries and the heart,” he says, “we really don’t know much about it.”
He’s recruiting 60-100 Central Texans between ages 40 and 75 to participate in a six-month exercise program. They’ll be put in three groups: One will do weight training only, the second will do weight training and aerobic training, and the third, the control group, will do stretching exercises.
“The idea is that if you perform regular weight training, could you reverse or prevent those age-related hardening of arteries,” he says.
The weight training won’t be too demanding, Tanaka says.
“More like 8-12 repetitions max so it’s not hard, strenuous weight training,” he says. “It’s typical weight training that is usually prescribed if you hire a personal trainer.
The project will also include gene profiling of the participants, which will help determine if a particular exercise program is better for them before they start training.
The project continues Tanaka’s interest in aging and the cardiovascular system.
It’s not all exercise all the time in Hirofumi Tanaka’s lab. Tanaka and Miriam Cortez-Cooper check a research participant’s vital signs.
“In the past 10 years the most profound changes in association with aging that has been identified has been hardening of the arteries because that causes an increase in blood pressure as you get old,” he says. “It also causes heart attacks and sudden deaths. So clinically it’s a very important function.”
Tanaka, a native of Japan, is an exerciser. He lifts weights three times a week, runs twice a week, plays soccer in a city league on weekends and coaches youth soccer.
“I try to practice what I preach,” he said.
The Costill influence
Tanaka’s interest in exercise physiology began when he was an undergraduate in Japan. He was determined to study under the top person in the field, David Costill, who headed the Human Performance Laboratory at Ball State University for many years.
“I was really interested in endurance exercise performance and every time I read an interesting paper, David Costill’s name is on the paper,” Tanaka says. “I thought, ‘This guy is a god. I’ve got to study under this guy.’”
Tanaka did study with Costill, and earned his master’s degree at Ball State. Tanaka worked construction for six months to earn the money to come to the United States.
Resistance is useful
When people think about weight training, they tend to think about spending arduous hours in the gym amid bulging biceps and clanking iron.
But, owing to the research conducted in the past 30 years, we know that it does not take much to gain muscle strength when you start weight lifting for the first time.
Tanaka’s lab recommends just one set of 8-10 weight training exercises as there is not much difference in how much strength you gain when you perform one set or three sets of weight training exercises.
The intensity of weight training does not have to be vein-bulging, either. Greater strength can be achieved with the weight that you can lift 10-15 times with moderate intensity.
These exercise prescriptions are not that much different for different age groups. For example, exercise prescriptions for healthy adults and children are almost identical.
Read an excerpt of exercise tips from the National Institutes of Health.
Tanaka has a personal connection with cardiovascular problems. His father had an aortic dissection, a tear in an artery that can result in death if not found quickly. It’s what killed actor John Ritter. Tanaka’s father recovered.
“That made me think that we should focus on the prevention of cardiovascular disease and that’s how I got into this field,” he said.
In other research, Tanaka found counter-intuitive results in the aerobic capacity of endurance-trained athletes as they age. The aerobic capacity—the ability to convert oxygen to energy—falls off more dramatically for trained men in middle and older age than in their sedentary peers who haven’t been active. But the active men still had higher aerobic capacity than the couch potatoes.
Inspiration from Mellencamp
In a study that’s nearing completion, Tanaka and a Japanese colleague are studying physically active people who smoke. The idea is to see if exercise can prevent a smoking-induced decrease in cardiovascular function and reduce the risk factors.
He got the idea for the study while watching a television show about singer John Mellencamp, who had a heart attack in 1994. Mellencamp couldn’t give up smoking so he started exercising.
Tanaka became involved with the Japanese researcher on the project because he had trouble finding Americans who exercise and smoke. That’s more common in Japan—even Tanaka smoked when he played soccer in college.
The results of that research should be out soon.
Photos: Marsha Miller
A Word to the Wise: Exercise Tips
—from Exercise and Aging, The NIH Word on Health, April 2003
- Check with your doctor before starting any exercise program.
- Do strength exercises for all your major muscles groups (shoulders, arms, back, stomach, hips, legs) at least twice a week. Don’t do exercises of the same muscle group two days in a row. Give your muscles time to recover and rebuild.
- Start out slow. You may need to start with one to two pounds of weight, or no weight at all. Don’t start out with too much weight, which can lead to injuries. You should feel like you’re challenging yourself, but aren’t near your limit.
- You may experience some muscle soreness and fatigue at the beginning. This is normal, and indicates your muscles are rebuilding to become stronger. However, you should not experience sore joints or exhaustion, nor should you experience any pain.
- You can use hand or ankle weights sold in sporting goods stores. Or you can be creative and fill empty milk jugs with sand or water, fill socks with beans or use canned goods.
- Do 8-15 repetitions in a row of each exercise. Use smooth and steady movements. Once you can easily lift the weight 15 times, increase the amount of weight (usually every two to three weeks). Your muscles will get continuously stronger as you progress.
- Take three seconds to lift or push a weight, hold the position for one second, and then take another three to five seconds to lower the weight (don’t just let the weight drop).
- Breath out (exhale) as you lift or push the weight, and breath in (inhale) as you relax or lower the weight. You will have to think about this at first, but soon it will become natural. Don’t hold your breath during the exercises.
If you spend time in a weight room or around people that regularly do strength exercises, you might overhear the following terms:
- One Repetition Maximum (1RM): The maximum amount of weight that can be lifted one time. Some strength programs are designed based on this amount. For example, a person may train with an amount of weight that is 50 percent or 80 percent of 1RM.
- Repetition (rep): The number of times in a row a weight is lifted. Eight to 15 repetitions are usually done.
- Set: A series of repetitions. For example, doing ten repetitions would be one set. Resting and then doing ten more repetitions would be another set, for a total of two sets. One set is all that is needed to get substantial benefits.
- Frequency: This refers to the number of workouts per week. A frequency of at least two times per week is recommended.
- Concentric Contraction: A type of muscle contraction where your muscle fibers shorten to produce force. This happens when you lift or raise a weight.
- Eccentric Contraction: A type of muscle contraction where your muscle fibers lengthen while they produce force. This happens when you lower the weight back down. This type of contraction is mainly responsible for the feeling of soreness after exercise. The soreness results from microscopic damage to the muscle cells that then stimulates them to regenerate and get stronger.
- Sarcopenia (pronounced sar-ko-PEEN-ya): The decrease in muscle tissue that occurs with aging. This is an active area of research and you will probably hear this term increasingly used as scientists learn more about it.