Tag Archives: exercise

The Role of Exercise in Maintenance of Weight Loss In Women

Posted on June 21, 2012 | 2 comments

A 2008 article in Archives of Internal Medicine teaches us the role of regular physical activity in keeping lost weight from returning to once-overweight women.

Methodology

201 overweight women (body mass index 27-40) aged 21 to 45 wanted to lose excess weight. They were sedentary at baseline, exercising fewer than three days a week for under 20 minutes. Sound familiar? Depending on baseline weight, the participants were assigned to eat either 1200 or 1500 calories per day, and to exercise according to one of four different exercise programs. Exercise recommendations were to burn a certain number of calories per week (1000 or 2000 calories) at either moderate or vigorous intensity. There were weekly group meetings for discussion of eating and exercise for the first six months, twice monthly meetings during the next 6 months, and monthly for the next six months. There was telephone contact for between months 19 to 24. This is pretty intense contact. Each participant was given a treadmill to use at home, but my impression is that other forms of exercise were permitted and discussed.

Ten subjects were excluded from follow-up analysis, mostly because they got pregnant. Nineteen others lost interest and dropped out.

Participants self-reported their physical activity levels.

At 24 months into the study, 170 of the original 201 participants were able to provide objective weight loss data.

Findings

Of the 170 subjects available for full analysis at 24 months, 54 either gained weight or lost none. Thirty-three lost 0 to 4.9% of initial body weight, 36 lost 5 to 9.9% initial body weight, and 47 (24.6%) lost 10% or more of initial body weight. (Who says diets don’t work?)

People who lost 10% or more of initial body weight at 24 months reported performing more physical activity – 275 minutes a week – compared with those who lost less than 10% of initial body weight. This amount of exercise equates to 55 minutes of exercise on five days per week above the baseline level of activity, which was sedentary as you recall. Whether they were assigned to “moderate” or “vigorous” exercise intensity didn’t seem to matter. Whether they actually performed at the assigned level is unclear.

These women who sustained a weight loss of 10% or more of initial body weight at 24 months were burning 1835 calories a week in physical activity.

Women who lost less than 10% of initial body weight, or lost no weight, exercised an average of 34 minutes a day on five days a week.

By 24 months, participants on average had regained about half of the weight they had lost during the first six months [which is typical].

Take-Home Points

After six months of dieting, many people start to regain half of what they lost. We saw this phenomenon recently in the Israeli study of low-fat vs low-carb vs Mediterranean diet.

If you have a lot of excess fat to lose, you have to wonder if it would make sense to start a different diet program every six months, until you reach your weight goal. Maybe there’s something about the novelty and excitement of a new diet program that keeps you motivated and disciplined for six months.  For someone with lots of weight to lose, I wonder if they’d do better switching to a new diet every six months.

The authors note there are few similar long-term studies examining the amount and intensity of physical activity needed to improve weight loss success. So this is important new information.

In using exercise to help prevent weight regain, it may not matter whether the exercise is moderate or intense.

The authors write:

…the inability to sustain weight loss appears to mirror the inability to sustain physical activity.

Long-term sustained weight loss is possible for a significant portion of overweight women. Although most women won’t do it, success is enhanced by exercising for 55 minutes on five days a week. Most men won’t exercise that much either. Which camp do you fall into?

For physical activity instruction and information, visit Shape Up America!, Physical Activity for Everyone, or Growing Stronger: Strength Training for Older Adults.

Steve Parker, M.D.

Reference: Jakicic, John M., et al. Effect of Exercise on 24-Month Weight Loss Maintenance in Overweight Women. Archives of Internal Medicine, 168 (2008): 1,550-1,559.

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My Fitness Experiment No. 3

Posted on May 22, 2012 | 9 comments

OK, here’s the new plan.

For aerobic and cardiovascular endurance:

  • twice weekly 15-minute treadmill high intensity interval training

For strength:

Twice weekly…

Why dumbbell weights?  ‘Cuz that’s what I’ve got.

I chose push-ups over bench presses because the former probably uses more muscles.

My hesitation about the pull-ups/chin-ups is that they may be redundant, i.e., working muscles already used in the other exercises.

Rather than counting sets and repetitions (e.g., three sets of 10 pushups), I’m going to continue using the exhaustion technique Chris Highcock taught me in Hillfit:

  • 90 seconds on each exercise
  • use enough weight that I’m exhausted after the 9o seconds
  • 10 seconds up and 10 seconds down for each repetition

If I skip the pull-ups, I could probably get the resistance training done in 20 minutes.  (I think I’m talking myself out of the pull-ups!)

My current fitness measurements are recorded elsewhere.  I’ll recheck after about six weeks.

None of this is etched in stone.

My goals are here.  Comments?

Steve Parker, M.D.

Notes

My fitness experiment No.1 was Mark Verstegen’s Core Performance.  No. 2 was Chris Highcock’s Hillfit.

Update May 22, 2012

The first workout went well.  I need to review the various types of dumbbell presses and decide which one I want to stick with.   Not doing the pull-ups/chin-ups.  I hope I’m a little sore tomorrow.  These are the dumbbell weights I used today:

Dumbbell squats: 25 lb (11.4 kg)

Push-ups: 25 lb (11.4 kg) in backpack

Dumbell presses: 15 lb (6.8 kg)

Romanian deadlift with dumbbells: 30 lb (13.6 kg)

Bent-over one-arm rows: 25 lb (11.4 kg)

Update May 25, 2012

I was sore in the back, quads (anterior thighs), and arms the next day.  I even postponed my second workout of the week for one day to allow lingering right arm soreness to resolve.  For my workout today, I reduced the overhead press weight from 15 to 10 lb.

Update May 27, 2012

Right arm/shoulder soreness is gone.  Now I’ve got soreness in my left hamstring, likely a strain related to the deadlifts.  Started 24 hours after my second workout in this experiment, and persisting 36 hours at this point.

Update May 28, 2012

Right hamstring soreness almost gone.  Instead of 30 lb dumbbells with the Romanian deadlift, I cut to 25 lb to avoid aggravating that hamstring.  Probably back to 30 lb next time.  With bent-over rows, I’m ready to progress to 30 lb.

Update June 9, 2012

It’s going well.  No injuries; no unusual aches.  Here are the dumbbell weights I carry in each hand: for squats – 30 lb; for push-ups – 25 lb in backpack; for dumbbell presses – 25 lb; for Romanian deadlifts – 40 lb; for bent-over row – 30 lb.  The set of dumbbells my wife got for me (used) in CraigsList was from 5 to 30 lb.  So I had to go buy a 40-lb pair, which set me back about $80 (USD).

Update June 26, 2012

Going well.  No injuries.  Haven’t missed any sessions.  Had to decrease backpack push-up weight from 25 to 20 lb  about 10 days ago—I just couldn’t keep up the exercise for 90 seconds at the higher weight.  A couple weeks ago I increased the bent-over row and squat weights to 40 lb.  I’m noticing much use of back and shoulder muscles when I’m doing exercises that superficially seem to target other muscles. E.g., the Romanian deadlifts and squats target the buttocks and thighs, but having to carry 40 lb in each hand works out my arms, shoulders, and back.

Update July 9, 2012

Having started my current fitness experiment six weeks ago, it’s time for a retest of my fitness to assess results.  But I’m not going to do it now.  I was at my son’s Boy Scout camp all last week and unable to do my regular routine.  (By the way,  jogging at 6,700 feet above sea level is definitely harder than at 2,000 feet.)  I’m going to do another two weeks of the program, then test.  Fair enough?  I’m a little concerned about some mysterious pain in my left forefoot that started roughly two months ago.  That may prevent my work on the treadmill.

Update July 21, 2012

I finished Fitness Experiment No.3 today and will retest my fitness after a couple days.  Originally planned as a six-week trial, I missed week six due to Boy Scout camp.  I made up for that by doing another two weeks.  I’m happy with my push-ups, dumbbell presses, and dumbbell squats.  By happy, I mean I get a good, exhausting workout in the allotted 90 seconds.  With push-ups, I wear a backpack holding 20 lb (9 kg).  Presses are with 30 lb (14 kg) in each hand.  Squats are with a pair of 40 lb (18 kg) dumbbells.  The bent-over one-arm rows have just now become too easy at 40 lb.  I’m not pleased with the Romanian deadlifts while holding 40 lb in each hand—they’re too easy.  I don’t have any heavier weights, so I’m looking at buying a pair of 50s for about $100 (USD) new, or $50 used.  Or I could 1) make the deadlifts more stressful in some way, 2) do them for longer than 90 seconds, or 3) find a substitute for the deadlifts.

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Whither My Fitness?

Posted on May 20, 2012 | 3 comments

I spent six hours yesterday considering a new fitness program for myself.  I’ve been happy with my Hillfit experience but want to try something new.

I surfed the ‘net, read some chapters in Jonathan Bailor’s The Smarter Science of Slim, and thought more about the Hillfit program.  I spent a lot of time at the Whole9 website reviewing their recent three-part series on “The Five Best Exercises for Overall Fitness, Health, and Longevity,” or some such.

Bailor’s exercise program focuses on eccentric exercise, a place I’m not ready to explore.  “Eccentric” probably doesn’t mean what you think.  Take pull-ups or chin-ups, for example.  You pull yourself up, which is concentric; letting yourself down is eccentric.  I’ll get to Bailor’s program some other day.

I was planning to put something together based on the Whole9 series, like Clifton Harski did.

My ideas started to crystallize after I remembered an old architectural aphorism: Form follows function.

So I asked myself, “Self, what are you’re goals?”:

  • improve my current fitness level
  • effective
  • efficient (e.g., not time-consuming, so under two hours a week)
  • scalable
  • teachable
  • relatively safe
  • simple
  • no machines or commercial gym needed (i.e., home-based)

A couple items from Whole9 caught my fancy: man-makers, Turkish get-ups, the primacy of squats, the High Knee Walk to Spiderman with Hip Lift and Overhead Reach.  Except for squats, these ideas were new to me.  The Spiderman thing brought some of Mark Verstegen’s Core Performance exercises to mind; particularly good for flexibility.

Do you know of a good existing pre-packaged program that meet’s my criteria, either in book or DVD form?  I’m sure there are hundreds available.

I’ll share more ideas with you in the next few days.

Steve Parker, M.D.

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The Whole9 “Five Best Exercises” Series

Posted on May 1, 2012 | 1 comment

Thanks to Meredith @HIITMama for bringing this project from Whole9 to my attention:

We brought together 12 fitness experts from a broad range of backgrounds–with bodies of experience ranging from weightlifting to track and field to mixed martial arts, and over two centuries of collective coaching experience–to ask them all the same question:

If you could only perform five exercise movements for the rest of your life, which five would you do? (Assuming your goals are general health, fitness and longevity, and not a specialized sport)*.

The answers may surprise you.

If you want an effective and time-efficient fitness program, I’d review this series carefully.  You may have to research some terms like Turkish get-ups, farmer carries, and dips.  Find examples at YouTube.

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“But Doc, I’m Too Heavy to Exercise!”

Posted on April 23, 2012 | 4 comments

I’ve written elsewhere about the death-defying aspect of exercise and myriad other health benefits of regular physical activity.

Very heavy folks potentially have more to gain in terms of health and longevity compared to skinny people. So it’s a cruel irony that the heavier you are, the harder it is exercise. At some point even light exercise becomes impossible.

Average-height women tipping the scales at about 280 pounds (127 kg) and men at 360 pounds (164 kg) aren’t going to be able to jog around the block, much less run a marathon. These weights are 100 percent over ideal or healthy levels. An actual “exercise program” probably won’t be possible until some weight is lost simply through very-low-carb eating, calorie restriction, or bariatric surgery. The initial exercise goal for you may just be to get moving through activities of daily living and perhaps brief walks and calisthenics while sitting in a chair.

“I’ll get started after I finish this cigarette.”

Markedly obese people who aren’t up to the aforementioned extreme weights can usually tolerate a low-intensity physical activity program. At 50 percent over ideal weight, an average-height woman of 210 pounds (95 kg) is carrying 70 excess pounds (32 kg) of fat. Her male counter-part lugs around 90 pounds (41 kg) of unnecessary fat. This weight burden causes dramatic breathlessness and fatigue upon exertion, and makes the joints and muscles more susceptible to aching and injury.

If you’re skinny, just imagine trying to walk or run a mile carrying a standard five-gallon (19 liter) water cooler bottle, which weighs only 43 pounds (19.5 kg) when full. The burden of excess fat makes it quite difficult to exercise.

If you’re markedly obese, several tricks will enhance your exercise success. I want you to avoid injury, frustration, and burn out. Start with light activity for only 10 or 15 minutes, gradually increase session length (e.g., by two to four minutes every two to four weeks) and increase exercise intensity only after several months. Your joints and muscles may appreciate easy, low-impact exercises such as stationary cycling, walking, swimming, and pool calisthenics/water aerobics.

You may also benefit from the advice of a personal fitness trainer arranged through a health club, gym, or YMCA/YWCA. Check out several health clubs before you join. Some of them are primarily meat markets for beautiful slender yuppies. You may feel more comfortable in a gym that welcomes and caters to overweight people. Hospitals are increasingly developing fitness centers with obese orthopedic, heart, and diabetic patients in mind.

Steve Parker, M.D.

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Random Notes on Fitness

Posted on April 19, 2012 | 2 comments

About couple years ago, I was thinking about putting together a fitness program for myself.  My goals were endurance, strength, less low back aching, flexibility, longevity, and being able to get on my horse bareback without a mounting block or other cheat.

I spent quite a bit of time at Doug Robb’s HeathHabits site.  He has a post called The “I don’t have time to workout” Workout.  I ran across some paper notes I made during my time there.  Doug recommended some basic moves to incorporate: air squat, Hindu pushup, dragon flag, shuffle of scissor lung, Spiderman lung, hip thrust/bridge, swing snatch, dumbbell press, Siff lunge, jumping Bulgarian squat, band wood chops, leg stiff leg deadlift.  Click the link to see videos of most of these exercises.  The rest you can find on YouTube.

Another post is called “Do you wanna get big and strong? -Phase 1”.  The basic program is lifting weights thrice weekly.  Monday, work the chest and back.  Tuesday, legs and abs/core.  Friday, arms and shoulders.

  • Chest exercises: presses (barbell or dumbell, incline, decline, flat, even pushups with additional resistance  – your choice
  • Back: chins or rows
  • Legs: squats or deadlifts
  • Arms and shoulders: dips, presses, curls

Doug is a personal trainer with a huge amount of experience.  He’s a good writer, too, and gives away a wealth of information at his website.

Around this same time of searching a couple years ago, I ran across Mark Verstegen’s Core Performance, Mark Lauren’s book “You Are Your Own Gym,”  and Mark Sisson’s free fitness ebook that also  features bodyweight exercises.

Lauren is or was a Navy Seal trainer.  His plan involves 30 minutes of work on four days a week and uses minimal equipment.  Lots of good reviews at Amazon.com.

Newbies to vigorous exercise should seriously consider using a personal trainer.

Steve Parker, M.D.

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Exercise Prevents Death

Posted on April 19, 2012 | 1 comment

January 1 this year, many folks made New Years’ resolutions to start exercising in conjunction with their other resolution to lose excess weight. I’ve got bad news for them.

Exercise is overrated as a pathway to major weight loss. Sure, a physically inactive young man with only five or 10 pounds (2 to 4 kg) to lose might be able to do it simply by starting an exercise program. That doesn’t work nearly as well for women. The problem is that exercise stimulates appetite, so any calories burned by exercise tend to be counteracted by increased food consumption.

“Should I go with aerobic or strength training….?”

On the other hand, exercise is particularly important for diabetics and prediabetics in two respects: 1) it helps in avoidance of overweight, especially after weight loss, and 2) it helps control blood sugar levels by improving insulin resistance, perhaps even bypassing it.

Even if it doesn’t help much with weight loss, regular physical activity has myriad general health benefits. First, let’s look at its effect on death rates.

EXERCISE PREVENTS DEATH

As many as 250,000 deaths per year in the United States (approximately 12% of the total) are attributable to a lack of regular physical activity. We know now that regular physical activity can prevent a significant number of these deaths.

Exercise induces metabolic changes that lessen the impact of, or prevent altogether, several major illnesses, such as high blood pressure, coronary artery disease, diabetes, and obesity. There are also psychological benefits. Even if you’re just interested in looking better, awareness of exercise’s other advantages can be motivational.

The traditional Mediterranean diet of the mid-20th century may owe some of it’s healthfulness to a physically active lifestyle.

Exercise is defined as planned, structured, and repetitive bodily movement done to improve or maintain physical fitness.

Physical fitness is a set of attributes that relate to your ability to perform physical activity. These attributes include resting heart rate, blood pressure at rest and during exercise, lung capacity, body composition (weight in relation to height, percentage of body fat and muscle, bone structure), and aerobic power.

Aerobic power takes some explanation. Muscles perform their work by contracting, which shortens the muscles, pulling on attached tendons or bones. The resultant movement is physical activity. Muscle contraction requires energy, which is obtained from chemical reactions that use oxygen. Oxygen from the air we breathe is delivered to muscle tissue by the lungs, heart, and blood vessels. The ability of the cardiopulmonary system to transport oxygen from the atmosphere to the working muscles is called maximal oxygen uptake, or aerobic power. It’s the primary factor limiting performance of muscular activity.

Aerobic power is commonly measured by having a person perform progressively more difficult exercise on a treadmill or bicycle to the point of exhaustion. The treadmill test starts at a walking pace and gets faster and steeper every few minutes. The longer the subject can last on the treadmill, the greater his aerobic power. A large aerobic power is one of the most reliable indicators of good physical fitness. It’s cultivated through consistent, repetitive physical activity.

Physical Fitness Effect on Death Rates

Regular physical activity postpones death.

Higher levels of physical fitness are linked to lower rates of death primarily from cancer and cardiovascular disease (e.g., heart attacks and stroke). What’s more, moving from a lower to a higher level of fitness also prolongs life, even for people over 60.

Steve Parker, M.D.

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Why Should I Care About Target Heart Rate?

Posted on April 18, 2012 | Comments Off on Why Should I Care About Target Heart Rate?

To get the full health benefits of regular physical activity, you need to put some effort into it. A leisurely hour-long stroll in the mall while window-shopping doesn’t pass muster, although that’s better than nothing.

One rough way to gauge whether you’re working hard enough during aerobic exercise is to monitor your heart rate, also known as pulse. Subtract your age from 220. The result is your theoretical maximum heart rate in beats per minute. Your heart rate goal, or target, during sustained aerobic exercise is a pulse that is 60 to 80 percent of your theoretical maximum pulse. For example: maximum heart rate for a 40-year-old is 180 (220 – 40 = 180), so the target heart rate zone during exercise is between 108 and 144 (60 to 80 percent of 180). Exceeding the upper end of the target zone is usually too uncomfortable to be sustainable. Exercise heart rates below the target zone suggest you’re not working hard enough to reap the full long-term benefits of aerobic exercise.

Here’s how to determine your pulse. After five or 10 minutes of exercise, stop moving and place the tips of your first two fingers lightly over the pulse spot inside your wrist just below the base of your thumb. Count the pulsations for 15 seconds and multiply the number by four. The result is your pulse or heart rate. It will take some practice to find those pulsations coming from your radial artery. If you can’t find it, ask a nurse or doctor for help.

Like all rules-of-thumb, this target heart rate zone isn’t always an accurate gauge of cardiovascular workout intensity. For instance, it is of very little use in people taking drugs called beta blockers, which keep a lid on heart rate.

As you become more fit, you’ll notice that you have to work harder to get your heart rate up to a certain level. This is a sure sign that your heart and muscles are responding to your challenge. You may also want to monitor your resting heart rate taken in the morning before you get out of bed. Unfit, sedentary people have resting pulses of 60 to 90. Athletes are more often in the 40s or low 50s. Their hearts have become more efficient and just don’t need to beat as often to get the job done.

As you become more fit, you’ll also notice that you have more energy overall and it’s easier to move about and handle physical workloads. You’ll feel more relaxed and have a sense of accomplishment. Expect these benefits eight to 12 weeks after starting a regular exercise program.

Steve Parker, M.D.

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Getting Started With Strength Training

Posted on April 16, 2012 | Comments Off on Getting Started With Strength Training

What’s “strength training”? It’s also called muscle-strengthening activity, resistance training, weight training, and resistance exercise. Examples include lifting weights, work with resistance bands, digging, shoveling, yoga, push-ups, chin-ups, and other exercises that use your body weight or other loads for resistance.

Strength training three times a week increases your strength and endurance, allows you to sculpt your body to an extent, and counteracts the loss of lean body mass (muscle) so often seen during efforts to lose excess weight. It also helps maintain your functional abilities as you age. For example, it’s a major chore for many 80-year-olds to climb a flight of stairs, carry in a bag of groceries from the car, or vacuum a house. Strength training helps maintain these abilities that youngsters take for granted.

According to the U.S. Centers for Disease Control and Prevention: “To gain health benefits, muscle-strengthening activities need to be done to the point where it’s hard for you to do another repetition without help. A repetition is one complete movement of an activity, like lifting a weight or doing a sit-up. Try to do 8–12 repetitions per activity that count as 1 set. Try to do at least 1 set of muscle-strengthening activities, but to gain even more benefits, do 2 or 3 sets.”

If this is starting to sound like Greek to you, consider instruction by a personal trainer at a local gym or health club. That’s a good investment for anyone unfamiliar with strength training, in view of its great benefits and the potential harm or waste of time from doing it wrong. Alternatives to a personal trainer would be help from an experienced friend or instructional DVD. If you’re determined to go it alone, Internet resources may help, but be careful. Consider “Growing Stronger: Strength Training for Older Adults” (http://www.cdc.gov/physicalactivity/downloads/growing_stronger.pdf). Don’t let the title turn you off if you’re young—its a good introduction to strength training for folks of any age. Doug Robb’s blog, HealthHabits, is a wonderful source of strength training advice (http://www.healthhabits.ca/).

People with diabetes must be particularly cautious before starting a fitness program.

Current strength training techniques are much different than what you remember from high school 30 years ago—modern methods are better. Some of the latest research suggests that strength training may be even more beneficial than aerobic exercise.

Steve Parker, M.D.

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Target Heart Rate

Posted on April 7, 2012 | Comments Off on Target Heart Rate

To get the full health benefits of regular physical activity, you need to put some effort into it. A leisurely hour-long stroll in the mall while window-shopping doesn’t pass muster, although that’s better than nothing.

One rough way to gauge whether you are working hard enough during aerobic exercise is to monitor your heart rate, also known as pulse. Subtract your age from 220. The result is your theoretical maximum heart rate in beats per minute. Your heart rate goal, or target, during sustained aerobic exercise is a pulse that is 60 to 80 percent of your theoretical maximum pulse. For example: maximum heart rate for a 40-year-old is 180 (220 – 40 = 180), so the target heart rate zone during exercise is between 108 and 144 (60 to 80 percent of 180). Exceeding the upper end of the target zone is usually too uncomfortable to be sustainable. Exercise heart rates below the target zone suggest you’re not working hard enough to reap the full long-term benefits of aerobic exercise.

Here’s how to determine your pulse. After five or 10 minutes of exercise, stop moving and place the tips of your first two fingers lightly over the pulse spot inside your wrist just below the base of your thumb. Count the pulsations for 15 seconds and multiply the number by four. The result is your pulse or heart rate. It will take some practice to find those pulsations coming from your radial artery. If you can’t find it, ask a nurse or doctor for help.

Like all rules-of-thumb, this target heart rate zone isn’t always an accurate gauge of cardiovascular workout intensity. For instance, it is of very little use in people taking drugs called beta blockers, which keep a lid on heart rate.

As you become more fit, you’ll notice that you have to work harder to get your heart rate up to a certain level. This is a sure sign that your heart and muscles are responding to your challenge. You may also want to monitor your resting heart rate taken in the morning before you get out of bed. Unfit, sedentary people have resting pulses of 60 to 90. Athletes are more often in the 40s or low 50s. Their hearts have become more efficient and just don’t need to beat as often to get the job done.

As you become more fit, you’ll also notice that you have more energy overall and it’s easier to move about and handle physical workloads. You’ll feel more relaxed and have a sense of accomplishment. Expect these benefits eight to 12 weeks after starting a regular exercise program.

Steve Parker, M.D.

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