Tag Archive for: aerobic exercise

Isometric Exercise Lowers Blood Pressure

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This summer has seen several studies about exercise, so we’ll just continue with the flow from last week. The first study caught me by surprise: isometric exercise lowers blood pressure. When you do isometric exercises, you increase tension in a muscle without moving the joint, such as holding your leg still while you clench your thigh muscles; if you’ve got a wall, a chair, and a floor, you’ve got all you need. We don’t think of isometric, also called static exercise, as being effective in changing the dynamic flow of blood in the cardiovascular system. Let’s take a look at the study.

Researchers conducted a literature search of all published studies that examined the impact of any type of exercise on systolic blood pressure (SBP) and diastolic blood pressure (DBP.) They conducted a pairwise and network meta-analysis to see which exercise helped BP the most. The most important finding was that every form of exercise significantly reduced SBP and DBP when performed for two weeks and longer: aerobic exercise, dynamic resistance (weight) training, combined training, high-intensity interval training (HIIT), and isometric exercise.

When they compared the efficacy of the different forms, isometric exercise lowered SBP the most, followed, in order, by combined training, weight training, aerobic training, and HIIT.

To me, isometrics are somewhat easy to perform because it removes obstacles such as orthopedic issues or equipment. But why would it reduce blood pressure more than other modes of exercise? We’ll check that out on Saturday.

What are you prepared to do today?

        Dr. Chet

Reference: British J Sp Med Online July 2023. doi: 10.1136/bjsports-2022-106503

Aging Stressor: The Cardiovascular System

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The next three Memos before Christmas will identify the three major stressors of aging as I see them and the general solution to them. The first stressor of aging is the changes to the cardiovascular system (CV). Cells wear out in all systems at all ages, but there are some that stop replacing and repairing themselves in the CV. A few examples:

  • The sino-atrial node is the pacemaker of the heart. As we get older, some of the specialized nerve cells of this area are not replaced. That can cause abnormal heart rhythms such as atrial fibrillation.
  • The arteries can become less pliable, called arteriosclerosis, which can cause an increase in blood pressure. (Atherosclerosis, the buildup of plaque in arteries, can be considered a special type of arteriosclerosis and can happen at any age depending on genetics and lifestyle.)
  • The heart muscle can get damaged and be replaced with scar tissue. That automatically weakens the heart, which pumps less blood (called the ejection fraction) and reduces fitness levels.

The solution? CV exercise, also called aerobic exercise: walking, riding an exercise bike, swimming or water aerobics, or pulling a sleigh (just checking to make sure you’re reading.) It doesn’t matter which mode you choose as long as you move your body for 30 to 45 minutes per day most days of the week. You can’t reverse every effect of aging on the CV and other systems, but nothing impacts every system of the body like exercise does. Aging with a vengeance requires aerobic exercise within the limitations you currently have, and the younger you start, the more successful you’ll be.

What are you prepared to do today?

        Dr. Chet

Getting to the Exercise Sweet Spot

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Do you realize that five minutes is only 0.3% of a day? Can you really say you can’t at least begin to exercise? “Five minutes isn’t the issue—it’s the 45 minutes a day!” Yes, although 45 minutes is only a whopping 3% of your day, I know it can be hard to work it into your schedule. How about if you could cut the time spent in aerobic exercise in half, from 45 minutes to just over 20 minutes? Interested? Just remember there will be a price to pay.

High-Intensity Interval Training (HIIT)

HIIT as is currently practiced began about 2008 and has been the focus of a lot of research since 2017. The current version alternates very intense intervals from 30 seconds to four minutes with rest periods of at least four minutes; most common is one minute of high intensity and four minutes of rest. Understand that the intensity is an all-out effort, something most sedentary people cannot and should not do—yet.

Remember the price? It’s getting in good enough aerobic condition to be able to handle the increased intensity. When you’re fit enough, four 20-minute HIIT sessions per week can provide you with the exercise sweet spot. Just remember this is only aerobic fitness. Lifting weights, yoga, stretching—that’s all separate.

Intensity

Here’s the real reason I’m getting a knee replacement done: I can’t work hard enough on the exercise bike to reach my target heart rate. Thigh pain above my bad knee hinders me from getting there. I’ve been on the cycle for at least six months, and I’m tired of not getting the workouts I’m used to getting through running.

Although running is not in my future after the knee is replaced, walking will be as well as using the elliptical again. I can replace running with walking uphill in order to achieve the fitness effect I want. It’s not as good but it will give me some variety. I can handle the pain of high-intensity training once I no longer have this level of knee pain. And that’s why I’m doing the knee replacement now.

The Bottom Line

The exercise sweet spot isn’t as precise as I would like, but it does follow a logical progression. Some exercise is better than none; if you’re not exercising at all, start with five minutes. Aspire to at least 30 minutes per day at least four days a week, then work up to 45 minutes.

When you can handle that and your physician says it’s okay, then you can start HIIT training to increase your fitness in less time and still have time to get stronger and more flexible. Even at 45 minutes a day, that’s just 3% of your day committed to exercise. That commitment of time will reduce your risk of just about every degenerative disease, which will help you really live more days of your life and not just struggle through them. Isn’t that worth the investment?

What are you prepared to do today?

        Dr. Chet

Finding the Exercise Sweet Spot

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After last week’s Memos on a sweet spot for food intake, Paula asked if I could do the same thing for exercise. The sweet spot for exercise isn’t so much between not enough movement and too much movement—it’s really between not enough movement and too much time, because most of us never have enough time to do all we need to do. So how can we put in enough time to be healthier but not so much time it becomes unworkable?

If nutrition is complicated, exercise can be more so; that’s why I’m going to stick to just one aspect of exercise: aerobic exercise. While strength, flexibility, and stamina are important, the key to better health is aerobic exercise. How much aerobic exercise is necessary to reduce the risk of all forms of disease, from Alzheimer’s disease to ulcers? There are three answers, depending on your current fitness level.

Riley, our six-year-old grandson, has a motor that doesn’t stop. He would rather be running and jumping, playing tag or battle or anything rather than sitting. Even watching a movie is an aerobic experience for him as he acts out his interpretation of each scene; he does amazing fight scenes! Unfortunately, adults don’t move nearly as much as Riley; most of us no longer have jobs that require moderate or intense physical activity. If you’re sedentary (and even home-schooling three kids is sedentary), then any exercise is better than none. Three minutes is better than two, and 12 is better than 10. Walking, cycling, aerobics—it doesn’t matter. Moving some is better than hardly moving.

Is there a magic number? It’s dependent on exactly how little you move, either due to physical limitations, work, or prior disease. There’s nothing like the precise recommendations similar to nutrition we covered last week.

The ultimate goal? The second answer, based on the current recommendations from every medical and exercise association, is 30 to 45 minutes of aerobic exercise per day most days of the week. There are 1,440 minutes in a day; 45 minutes would represent about 3% of a day. That’s less than the 10% change in diet we talked about last week.

What is the third answer? For those who want to be fitter, I’ll let you know on Saturday. For now, some is better than none. Are you going to begin today?

What are you prepared to do today?

        Dr. Chet

Aging with a Vengeance and Your Proteome

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This year’s Super Bowl Webinar focused on aging with a vengeance—becoming the best version of yourself, no matter your age. The study we just reviewed on the proteome suggests that the people were healthier who were biochemically younger than their actual age. Here are the actions I believe can help at the three critical phases of aging that were identified in proteome study. As I find out more, I’ll be more specific.

31 to 37

If you have weight to lose, now is the time to lose it. Take it from me and my decades of experience with weight loss programs: it becomes more difficult the older you get. Find a way to eat that will maintain a reduced body weight and stick with it.

Reduce your protein intake. That may seem a little odd, but this is a time to focus on vegetables, fruit, whole grains, and quality oils.

Focus on your cardiovascular system by doing aerobic exercise on a regular basis. Use interval training to make the most of your time, and when you’re fit enough, you can add high-intensity interval training (HIIT) to your routine.

57 to 63

The kind of 80- to 85-year-old you’re going to be is dependent on what you do now. If you haven’t achieved a normal body weight, that’s a high priority just as it was in the prior age group. I know how difficult this is because it’s eluded me throughout my life; I lost a lot of weight and kept it off for years, but I’d still like to weigh less.

Increase protein intake to 1–1.5 grams per kilogram body weight per day.

Supplement your diet with essential amino acids. While the amounts are still not absolutely clear from the research, 10–20 grams per day is a good goal.

If you’re not already doing so, add weight training to your exercise routine. Start with using your own body weight, then add exercise tubes or light weights, and then use machines or free weights. Now is the time to retain or even increase your muscle mass.

75 and Older

If you haven’t achieved a normal body weight, there’s still time. My wonderful mother-in-law lost a significant amount of weight at this age, and she was an overweight diabetic in a wheelchair.

Increase protein intake to 1.5–2 grams per kilogram body weight per day. It’s difficult because appetite decreases and protein makes us feel full. It will help reduce the muscle loss that’s happening.

Supplement your diet with essential amino acids; the amounts are still between 10–20 grams per day.

Add weight training to your exercise routine. It will help you to retain or even increase your muscle mass. Stay within any orthopedic or other limitations, and get some help if you need to, but do it. Your primary caregiver will probably be glad to refer you to a physical therapist who can get you started safely.

The Bottom Line

For all that’s been written about healthy aging, we still don’t know very much. Healthy aging begins the day we are born, but we realize that only when it dawns on us that we’re aging. No matter your age, no matter your current state of health, it can be better. You can learn more in the replay of this year’s Super Bowl Webinar, but it will be available for only a little while longer.

The simple things I’ve talked about in this Memo are a beginning. When I know more, so will you. Inevitably, it comes back to a single question:

What are you prepared to do today?

        Dr. Chet

Reference: Nature Medicine. 2019. https://doi.org/10.1038/s41591-019-0673-2