Category Archives: Exercise

U.S. Kids Too Sedentary

Posted on January 7, 2013 | Comments Off on U.S. Kids Too Sedentary

“Only two out of five U.S. children in elementary school met both the physical activity and screen-time recommendations from the federal government and the American Academy of Pediatrics, researchers found.”

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Exercise Does and Doesn’t Help With Weight Loss

Posted on December 1, 2012 | Comments Off on Exercise Does and Doesn’t Help With Weight Loss

With regards to TV’s “The Biggest Loser” show:

The show’s 24-week regimen consists of approximately 4 hours of daily exercise, including 1 hour of intense resistance, 1 hour of intense aerobic activity, and 2 hours of moderate aerobic activity (for example, walking), along with a caloric  intake of at least 70% of estimated resting daily energy expenditure, explained Dr. [Robert] Huizenga, who is a former team physician to the L.A. Raiders football team.

exercise for weight loss and management, dumbbells

If you’re not familiar with resistance training, a personal trainer is an great idea

This is an excerpt from “The Biggest Loser Pushes Envelope on Diabetes,” in Internal Medicine News, vol. 45, No.11, page 17.

In a previous post about The Biggest Loser, I’d written that I didn’t know how much they exercised.

For purposes of discussion, let’s assume the documented major weight losses of Biggest Loser contestants is not simply due to caloric restriction.

Dr. Huizenga shared some of his experience at the recent annual meeting of the American Association of Clinical Endocrinologists.  In a study of 35 Biggest Loser participants, about half had prediabetes or type 2 diabetes.  Hemoglobin A1c, a measure of blood sugar control, fell significantly in this subset.  Three of the six with diabetes were able to stop metformin early on.  By week 29 of the study, average body mass index for the entire group had fallen from 46 to 29.

Yes, exercise helps with weight loss.  But most folks aren’t willing or able to exercise vigorously for four hours a day.  Physical activity is more important for maintenance of weight loss, when it demands much less time.

Steve Parker, M.D.

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Momentary Muscular Failure and Resistance Training

Posted on November 19, 2012 | 2 comments

I was planning to review here an article, Resistance Training to Momentary Muscular Failure Improves Cardiovascular Fitness in Humans: A review of acute physiological responses and chronic physiological adaptations.  It’s by James Steele, et al, in the Journal of Exercise Physiology (Vol. 15, No. 3, June  2012).

Exercise to momentary muscular failure may be safer on a machine

But it’s too technical for most of my readers. Heck, it’s too technical for me!  Too much cell biology and cell metabolism.  You’re dismissed now.  Maybe “American Idol” or “Honey Boo Boo” is on TV.

I’m just going to pull out a few pearls from the article that are important to me.  I ran across this in my quest for efficient exercise.  By efficient, I mean minimal time involved.

The authors question the widespread assumption that aerobic and endurance training are necessary for development of cardiovascular fitness.  Like Dr. Doug McGuff, they wonder if resistance training alone is adequate for the development of cardiovascular fitness.  Their paper is a review of the scientific literature.  The authors say the literature is hampered by an inappropriate definition and control of resistance training intensity.  The only accurate measure of intensity, in their view, is when the participant reaches maximal effort or momentary muscular failure.

The authors, by the way, define cardiovascular fitness in terms of maximum oxygen consumption, economy of movement, and lactate threshold.

“It would appear that the most important variable with regards to producing improvement in cardiovascular fitness via resistance training is intensity [i.e., to muscle failure].”

The key to improving cardiovascular fitness with resistance training is high-intensity.  These workouts are not what you’d call fun.

From a molecular viewpoint, “the adenosine monophosphate–activated protein kinase pathway (AMPK) is held as the key instigator of endurance adaptations in skeletal muscle.  Contrastingly, the mammalian target of rapamycin pathway (mTOR) induces a cascade of events leading to increased muscle protein synthesis (i.e.,[muscle] hypertrophy).”  Some studies suggest AMPK is an acute inhibitor of mTOR activation.  Others indicate that “resistance training to  failure should result in activation of AMPK through these processes, as well as the subsequent delayed activation of mTOR, which presents a molecular mechanism by which resistance training can produce improvement in cardiovascular fitness, strength, and hypertrophy.”

You’re not still with me, are you?

“… the acute metabolic and molecular responses to resistance training performed to failure appear not to differ from traditional endurance or aerobic training when intensity is appropriately controlled.”

Chronic resistance training to failure induces a reduction in type IIx muscle fiber phenotype and an increase in type I and IIa fibers.  (Click for Wikipedia article on skeletal muscle fiber types.)

“It is very likely that people who are either untrained or not involved in organized sporting competition, but you have the desire to improve their cardiovascular fitness may find value in resistance training performed to failure.  In fact, this review suggests that resistance training to failure can produce cardiovascular fitness effects while simultaneously producing improvements in strength, power, and other health and fitness variables. This would present an efficient investment of time as the person would not have to perform several independent training programs for differing aspects of fitness.”  [These statements may not apply to trained athletes.]

Before listing their 157 references, the authors note:

“It is beyond the scope of this review to suggest optimal means of employing resistance training (i.e., load, set volume, and/or frequency) in order to improve cardiovascular fitness since there are no published studies on this topic.”

In conclusion, if you’re going to do resistance training but not traditional aerobic/cardio exercise, you may not be missing out on any health benefits if you train with intensity.  And you’ll be done sooner.

Steve Parker, M.D.

PS: See Evidence-based resistance training recommendations by Fisher, Steele, et al.

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Small Study Shows Improved Diabetes and Prediabetes With Biggest Loser Plan

Posted on November 2, 2012 | 1 comment

“One more rep then I’m outa here!”

Do you wonder how much exercise it takes to lose a lot of weight quickly?  Read on.

TV’s “The Biggest Loser” weight-loss program works great for overweight diabetics and prediabetics, according to an article May 30, 2012, in MedPage Today.  Some quotes:

For example, one man with a hemoglobin A1c (HbA1c) of 9.1 [poor control of diabetes], a body mass index (BMI) of 51 [very fat], and who needed six insulin injections a day as well as other multiple prescriptions was off all medication by week 3, said Robert Huizenga, MD, the medical advisor for the TV show.

In addition, the mean percentage of weight loss of the 35 contestants in the study was 3.7% at week 1, 14.3% at week 5, and 31.9% at week 24…

The exercise regimen for those appearing on “The Biggest Loser” comprised about 4 hours of daily exercise: 1 hour of intense resistance training, 1 hour of intense aerobics, and 2 hours of moderate aerobics.

Caloric intake was at least 70% of the estimated resting daily energy expenditure, Huizenga said.

At the end of the program, participants are told to exercise for 90 minutes a day for the rest of their lives. Huizenga said he is often told by those listening to him that a daily 90-minute exercise regimen is impossible because everyone has such busy lives.

“I have a job and I work out from 90 to 100 minutes per day,” he said. “It’s about setting priorities. Time is not the issue; priorities are the issue.”

Of the 35 participants in this study, six had diabetes and 12 had prediabetes.  This is a small pilot study, then.  I bet the results would be reproducible on a larger scale IF all conditions of the TV program are in place.  Of course, that’s not very realistic.  A chance to win $250,000 (USD) is strong motivation for lifestyle change.  Can you see yourself exercising for four hours a day?

Steve Parker, M.D.

PS: Although not mentioned in the article, these must have been type 2 diabetics, not type 1.

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Fitness Experiment No. 4: Results

Posted on October 13, 2012 | 2 comments

For the last six weeks I’ve been working out twice weekly.  Twenty minutes of man-makers alternating with Turkish get-ups, followed by 15 minutes of high intensity intervals on the stationary bike.  So 70 minutes a week.  Click for details.

I re-tested my fitness today and compared with my numbers of July and August:

  • weight: no change (170 lb or 77.3 kg)
  • maximum consecutive push-ups: 36 before, 28 after
  • maximum consecutive pull-ups: 9 before, 8 after
  • maximum consecutive sit-ups: 34 before, 39 after
  • time for one-mile walk/run: 9 minutes and 30 seconds in August, down to 8 minutes and 30 seconds now
  • vertical jump (highest point above ground I can jump and touch): 276 cm in July, 277 cm now
  • toe touch (wearing shoes, stand and lock knees, bend over at waist to touch toes: 22 cm in July, 20 cm now

lessons learned

It’s not fun.  I’m glad it’s over.  It’s harder than Experiment No. 3.  The program significantly improved my 1-mile run time, but I did just as well with the more enjoyable Hillfit plus treadmill intervals (Experiment No. 2).  Total work-out time per week is about the same for all three programs.

I do sit-ups with my arms folded across my chest, hands on my shoulders

I’m disappointed in my big drop in total push-ups.  The increase in sit-up performance is cold comfort.

I’m enjoying the intervals on the bike more than the treadmill, and they’re probably easier on my lower limbs.

Although I can’t see myself doing this regimen long-term, I can imagine going back to it periodically just to mix things up, to avoid boredom.

Working harder doesn’t necessarily mean you’ll get better results.  Work smarter, not harder.

Steve Parker, M.D.

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The Secret to Prevention of Weight Regain

Posted on October 5, 2012 | 1 comment

“I couldn’t do this when I weighed 220 pounds.”

Regain of lost body fat is the most problematic area in the field of weight management.  Solves this problem for good, and you Nobel Prize in Medicine.

Why do most diets ultimately fail over the long run?  Because people go back to their old habits.

Here are the two secrets to prevention of weight regain:

1)    Restrained eating

2)    Regular physical activity

“Successful losers” apply self-restraint on a daily basis, avoiding foods they know will lead to weight regain.  They limit how much they eat.  They consciously choose not to return to their old eating habits, despite urges to the contrary.

The other glaring difference is that, compared to regainers, the successful losers are physically active.  Oftentimes, they exercised while losing weight, and almost always continue to exercise in the maintenance phase of their program.  This is true in at least eight out of 10 cases.  It’s clear that regular exercise isn’t always needed, but it dramatically increases your chances of long-term success.

Steve Parker, M.D.

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For Weight Loss, What’s More Important: Exercise or Food?

Posted on September 25, 2012 | Comments Off on For Weight Loss, What’s More Important: Exercise or Food?

This is NOT diet food

What you eat, and how much, are more important than your physical activity.  By far.

  • Your genetics largely determines your response to an exercise program
  • Physical activity isn’t a great way to lose weight
  • School-based or other programs to increase childhood physical activity probably won’t reverse childhood obesity statistics
  • Disregarding weight loss, exercise has other worthwhile metabolic advantages
  • Highly advanced societies shouldn’t blame our overweight problem on decreased levels of physical activity

Skyler Tanner slaughters some sacred cows in his blog post June 4, 2012. I pulled these bullet points from his post. Click on his embedded links for details.

Steve Parker, M.D.

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Fat or Fit: Which Is Healthier?

Posted on August 25, 2012 | Comments Off on Fat or Fit: Which Is Healthier?

Men live longer if they improve or maintain their fitness level over time, according to research out of the Cooper Clinic in Dallas, Texas. Part of that improved longevity stems from reduced risk of death from cardiovascular disease such as heart attack and stroke.

Compared with men who lose fitness with aging, those who maintained their fitness had a 30% lower risk of death; those who improved their fitness had a 40% lower risk of death. Fitness was judged by performance on a maximal treadmill exercise stress test.

Body mass index over time didn’t have any effect on all-cause mortality but was linked to higher risk of cardiovascular death. The researchers, however, figured that losses in fitness were the more likely explanation for higher cardiovascular deaths. In other words, as men age, it’s more important to maintain or improve fitness than to lose excess body fat or avoid overweight.

Steve Parker, M.D.

Reference: Lee, Duck-chul, et al. Long-term effects of changes in cardiorespiratory fitness and bodly mass index on all-cause and cardiovascular disease mortality in men. Circulation, 124 (2011): 2,483-2,490

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My Fitness Experiment No. 4

Posted on August 23, 2012 | 4 comments

And now for something completely different….

Push-ups are one of Chris Highcock’s favorite exercises

If you’re new here, let me fill you in.  I don’t like to exercise.  But I want the benefits of exercise.  So I’m experimenting with ways to gain the benefits with minimal time involvement.  I want to keep my costs down, too.  I’ve already demonstrated I’m fit enough to be in the U.S. Army while working out only 70 minutes a week.

The guys at Whole9 had a series of blog posts on “the five best exercises.”  That’s where I heard of Turkish get-ups and man-makers (see links to YouTube demo videos below).

Everybody has their own ideas as to the Big Five exercises, the ones that are critical to any well-rounded strength training program.  The finalists typically are squats, deadlifts, bent-over rows, bench presses, push-ups, overhead presses, and chin-ups (or pull-ups).  The Big Five aren’t necessarily the Five Best exercises.

Turkish get-ups and man-makers incorporate many of those big five moves.  For instance, the man-maker incorporates a squat, row, overhead press, and push-up.

I’m also interested in maintaining what I’ll call aerobic endurance: the ability to maintain a steady workload at a relatively high heart and breathing rate over a significant length of time.

Heres’ my new plan:

  • Alternate man-makers (MMs) with Turkish get-ups (TGUs) for 20 minutes twice a week, with 1-2 minutes of rest in the middle of the session
  • Finish the sessions with high-intensity intervals (HIT) on a stationary cycle:  easy warm-up for 3 minutes then 1 minute of hard and fast cycling alternating with 1 minute easy coasting while I catch my breath, for a total of 6 fast/slow cycles (15 minutes on cycle)

I did my first session yesterday and it kicked my butt.  The MMs are the most vigorous; at some point I just couldn’t do any more due to breathlessness and weakness, then I switched to TGUs.  After I got my breath back, I returned to the MMs, then alternated back and forth.  I did both MMs and TGUs with 15 lb (6.8 kg) dumbbells.  I’ll increase my weights as able.  I’m not sure the stationary cycle HIIT adds much to this regimen.

Here are YouTube examples of man-makers by SEAL Fit and Travis, and Turkish get-ups by Max Shank, Gray Cook, and Till Sukopp.  Some man-makers incorporate one push-up, others do two (one before each renegade row).  Here’s an video example of HIIT on a stationary cycle.

MMs and TGUs are scalable for most folks who are starting out in poor condition.  For instance, man-makers require a push-up but many people can’t do even one.  In that case, do a knee push-up.

Again, if one is starting out in poor shape, burpees could be substituted for man-makers; they’re similar.  Burpees can be done with knee push-ups or regular push-ups.  As fitness improves, you graduate to regular push-ups and man-makers with kettlebells or dumbbell weights.

I’ll admit I have some trepidation about hurting myself with this program!

Steve Parker, M.D.

Update August 25, 2012

Not pertinent, but a cool picture

I dragged the old Schwinn Airdyne in from the garage, dusted it off, and replaced the batteries.  Worked like a charm even though no one’s ridden it for eight years.  This war horse is at least 15 years old; we got it used, like my set of dumbbells.  My natural “coasting” speed is around level 2.4; my “damn the torpedoes, full speed ahead” speed is about level 5.5.  I burned 200 calories over 15 minutes, which is about what I did with my treadmill HIIT.  With the MMs, I stuck with 15 lb (6.8 kg) dumbbells.  For the TGUs, I increased to 20 lb (9 kg).  The MMs and TGUs are tough; I’m breathing fairly heavily for the entire 20 minutes.  Not fun.

Update October 6, 2012

This thing is not fun.  But I haven’t missed a session.  I look for excuses to postpone the workout.  After the hellish man-makers and Turkish get-ups, I look forward to the 15 minutes on the bike.  I can’t see keeping this up for the long run unless it pays off big, fitness-wise.

I have to guard against slacking off on my bike performance.  On the treadmill, by comparison, I dialed in the treadmill speed and had to keep up or I’d fall off the back.  No such risk, or motivation, on the bike.

A couple weeks ago I increased the man-maker weights to 20 lb (9 kg) and the Turkish get-up weights to 25 lb (11.4 kg).  I don’t think I’ll be able to increase those weights any time soon; already I’m so short of breath at times that I have to stop and rest for a minute.

My body’s holding up OK.  At one point, however, I developed some mild pain and swelling in my left knee that I thought could be a problem.  It cleared up after a few days and hasn’t recurred.

I’ve completed six weeks of Fitness Experiment No.4.  After resting a few days, I’ll retest my fitness.

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How Soon Does Fitness Deteriorate After You Stop Working Out?

Posted on August 19, 2012 | Comments Off on How Soon Does Fitness Deteriorate After You Stop Working Out?

The answer varies from person to person and may be different for aerobic versus  strength measures.

I’m reminded of a quote from a famous violinist: “If I don’t practice for one day, I can tell.  If I don’t practice for two days, my conductor can tell.  If I don’t practice for three days, the audience can tell.”

I laid off all exercise for the last three weeks, partly due to a long vacation, partly to see how much my fitness would deteriorate.

Here’s what I found:

  • My time for the one-mile run increased from 8 mins and 54 seconds to 9 mins and 30 seconds
  • My maximum number of push-ups increased from 32 to 36
  • My maximum number of sit-ups increased from 32 to 34
  • My maximum number of pull-ups increased from 8 to 9

Closing Thoughts

Strength measures increased, surprisingly.  Was it just a good day, or did my muscles need the time off to rest and re-build?  Over-training is a real problem for some folks.  At 20 minutes of weight-training twice a week, I doubt I was anywhere near what most consider over-training.  I don’t fiddle-fart around during my exercise sessions, but I’m not puking either.

So I won’t feel too bad in the future if I take a couple or three weeks off from strength training periodically.

My endurance for running deteriorated significantly.  Is it related to the lack of strength training, the lack of treadmill interval work, or both?

Your mileage will vary.

Steve Parker, M.D.

 

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