Tuesday, April 30, 2013

Important Article on Breast Cancer

In the cover article for the Sunday New York Times Magazine Peggy Orenstein surveys past and present thinking about breast cancer in light of her own experience.  In "Our Feel-Good War on Breast Cancer" she shows that women are  pressured into being treated for a DCIS, a condition that might not harm them until years later - or at all.  Women treated unnecessarily vastly outnumber those whose lives are actually saved by treatment.  The Komen Foundation lionizes cancer survivors while marginalizing women with untreatable cancer as though they had somehow failed.

In a recent blog post Orenstein adds other important material that did not make it into the article, notably the brave but unsung deeds of Rose Kushner.

My own experience with non-cancer was described in this blog post.

Saturday, April 20, 2013

Michael Mosley's Exercise, My Exercise

After watching “The Truth About Exercise” I wanted to find out more about Michael Mosley.  He is a writer, doctor, and producer and presenter of TV programs and he has been interested in getting into better shape for several years.  About five years ago, after turning fifty and assessing his situation, he tried a restricted calorie diet and human growth hormone shots.  Neither approach was a success.  “The Truth About Exercise” chronicled more recent efforts and this year there is a book, The Fast Diet, that recommends eating your typical diet five days per week and one-quarter that number of calories (about 500 or 600) two days per week.  Apparently this worked for Mosley, as we will be able to see on an upcoming three part series on PBS.

In “The Truth About Exercise” Mosley applied new ideas about exercise to his own situation.  While watching the show, I mentally compared his experience with what has happened to me as I have tried to lose weight and improve my fitness over the years.  Michael Mosley and I have some things in common: we both like wine, chocolate, and good food.  Neither of us is especially fond of exercise.  In other ways, though, we are opposites.  Mosley is a toffee.  He looks lean but he has visceral fat around his internal organs.  I have never looked lean (and probably never will because I’m so muscular) but my visceral fat is not high, 9 or 10 on the Tanita Ironman’s scale of 1-60.  

When Mosley visits Dr. Emma Ross he learns that his brain is actually keeping him from exercising as much as he is physically capable of doing.  Something like this happened to me about four years ago.  I had been doing interval training and working up to faster speeds on the cross trainer but I was starting to feel that it was too much, getting a little tired and light-headed, especially on hot days during the summer.  What got me past this obstacle was the metabolic training program I did with Greg and Susan Simmons. 

I exercised with a mask over my face that allowed Greg and Susan to monitor how my body was burning carbs and fat.  Based on my (very slow) metabolism, they designed an exercise program that would increase my aerobic base so that my body would become better at burning fat.  After that, we worked to increase my anaerobic threshold so that I could exercise at a higher intensity.  The workouts for this program were long and boring at first but I ended up being able to do a shorter, harder workout without feeling overstressed.  These days the aerobic part of my workout consists of a 33-minute series of intervals with heart rate averaging in the low 130’s, about 85% of maximum heart rate for me.  I do this routine twice a week. As part of the program Greg and Susan tested my VO2max, a measure of cardiovascular fitness.  It was a not-bad 39 and got up to 42.9 the last time they tested it.  Mosley’s was a not-bad 37 but didn’t change at all as a result of the HIT training he did.

Michael Mosley seems especially interested in reaching the 80% of people who never go to the gym.  The segment with Dr. James Levine emphasizes the importance of non-exercise activity thermogenesis (NEAT) and encourages people to walk, ride a bike, and take the stairs in order to burn more calories during the day.  For people who rarely get up and move around during the day this approach may really help, but for people who are already somewhat active it may not make enough of a difference.  At our house we doing our own cooking, cleaning, laundry, and most of the yard work but we still have to watch what we eat and go to the Y in order to keep from putting on weight!

Interval training has been the subject of a lot of research lately.  It seems to be pretty well established that interval workouts are more efficient and effective that long, steady cardio sessions.  What is less clear is exactly how the intervals should be done and whether this is the same for everyone.  HIT, per Professor Jamie Timmons, involves very short intervals of 20-30 seconds.  I tried short-interval workouts for a while and saw no improvement at all; I didn’t lose weight and my fitness didn’t improve.  I was in decent shape so my resting heart rate was low (50 bpm or so).  To raise my heart rate to the point where I was actually working (at least 120) took more than 20 seconds – the interval was over before it had even started.  When I did the resting part my heart rate would go right back down to 70 or so and still not get much above 120 on the next round.  For my present regimen, I warm up for five minutes to get my heart rate to the mid-120’s, which is a good starting point.  I then alternate intervals of four and three minutes at 125-130 bpm and 135-140 bpm, respectively, for an overall average of about 132 bpm.  The 33-minute workout I do burns 300 calories or less, according to my Polar heart rate monitor.  For my body, a 12-minute workout would probably have no effect at all.  

It’s great that HIT improved Mosley’s insulin sensitivity but I sometimes felt that both he and Timmons verged on saying that the 12-minute routine might be all the exercise a person needs.  Leaving aside the issue of what cardio is right for each person, there are many types of exercise that can improve the body in many different areas, including strength, agility, quickness, flexibility, and balance.  While encouraging non-exercisers to exercise is a thoroughly admirable goal, it is also important to encourage those who do a little to try to expand the range of what they can do and improve their condition even more.  

I wish the segments about HIT had included information about Mosley’s resting heart rate and whether that changed as a result of the HIT training.  Resting heart rate is an important index of fitness.  I try to keep mine in the 45-50 bpm range and I do the cardio intervals mostly for that purpose.  If I go on a trip and don’t work out for a couple of weeks it tends to creep back up but after a few workouts it comes right back down.  A recent Danish study showing that healthy men with a resting heart rate of 51-80 bpm had a 40-50% greater risk of death than those at or below 50 bpm.  At 81-90 bpm the risk was doubled and above 90 bpm it was tripled!

Saturday, April 13, 2013

Michael Mosley's "The Truth About Exercise"

This week I watched a fascinating show dealing with recent research on exercise.  “The Truth About Exercise,” which originally aired last year on the BBC, takes host Michael Mosley on a series of visits around the UK to learn about the new ideas and how they may be applicable to his own situation. 

The first stop is Loughborough University, where many UK Olympic hopefuls train, including hurdler Will Sharman.  Mosley asks the athlete whether he enjoys training and Sharman replies “There are some things within my training components that are grueling and I don’t enjoy them at the time.  It’s horrible.”  This corresponds pretty closely to Mosley’s own attitude toward exercise but he challenges Sharman to a race anyway.  During a practice run he pulls a muscle and falls down.  This event introduces the first truth about exercise, “You can easily hurt yourself if you’re not prepared.”

After this ignominious beginning, Mosley meets with Dr. Keith Tolfrey and goes for a jog around an outdoor track.  He wears a face mask that allows the scientist to measure how much oxygen and carbon dioxide he is using and calculate how many calories he is burning at his current pace.  At the rate of 16 calories per minute, Tolfrey tells him, it would take 55 minutes to burn off a cappuccino, a banana, and a blueberry muffin.  The moral? “If you really want to lose weight and keep it off, you have to control what you eat as well.”  On the other hand, even when exercise does not result in weight loss, it confers other benefits, like reducing the amount of fat circulating in the bloodstream.

In order to learn how this works, Mosley travels to his second destination, the University of Glasgow, where Dr. Jason Gill treats him to a huge Scottish breakfast, with fat equivalent to what most people eat in a day.  A comparison of blood samples from before and four hours after breakfast shows that the amount of fat in Mosley’s blood has doubled as a result of the meal.  This fat will end up as fatty deposits on the walls of the blood vessels and in other parts of the body.  The most dangerous scenario is that it may become visceral fat and surround internal organs such as the liver.  From a previous medical test, Mosley knows that he has too much visceral fat.  Also, his father was diabetic.  Dr. Gill then instructs Mosley to go for a long walk.   

The next day Mosley is served the same lavish breakfast but the walking has triggered an enzyme that offsets the effects of the meal.  When his blood is tested again four hours later, the amount of fat is one-third less than it was after the previous day’s breakfast.  The drawback is that the walk took 90 minutes, too much time to fit in on a regular basis.

Mosley’s third stop is the University of Nottingham, where Prof. Jamie Timmons is working to find ways to get more people to exercise.  Previous research by Timmons has shown that people respond to exercise in very different ways.  Based on a four-year study, Timmons and his colleagues determined that out of 1000 people 15% were over-responders to exercise, while 20% were non-responders who did not improve their fitness by exercising.  Eleven genes determine the category for any given individual.  Timmons also measures Mosley’s insulin sensitivity (a predictor of diabetes) and VO2max (an index of overall fitness).  Timmons then has Mosley do a HIT (high intensity training) routine in which he pedals as fast as he can on a stationary bike for 20 seconds, then rests, then repeats the process twice more for a total of one minute of exercise.  Mosley is instructed to repeat this sequence three times per week, three minutes of exercise in all.

At the fourth destination the focus shifts from intense exercise to non-exercise.  Dr. James Levine discusses NEAT (non-exercise activity thermogenesis), which is the miscellany of up-walking-around movement that each person does each day.  Mosley and two other people are equipped with special underwear that measures how active they are and Mosley turns out to be very sedentary.  Over the next 24 hours he makes a conscious effort to be more active, walking, riding a bike, and taking the stairs rather than the elevator.  With very little effort he burns an additional 500 calories compared with the previous day.  According to Levine, new studies show that being sedentary is very destructive to the body.  He says, “There should never be an hour when you’re sitting down.”  Even people who go to the gym may not be doing enough if they are sitting for most of the day.

In order to learn about the influence of the subconscious brain on exercise Mosley makes his fifth journey, to visit Dr. Emma Ross at the University of Brighton.  There he exercises in a low-oxygen chamber and discovers that the brain can be like an overly cautious parent influencing a person to work less hard than he is actually capable of doing.  With additional sessions he finds that he is able to do more than he could at first. 

Mosley has now been following the 12-minutes-per-week HIT routine for one month and he returns to Jamie Timmons to learn whether the program has affected his fitness.  The good news is that his overall insulin sensitivity has improved by 23%, a welcome surprise given his family history of diabetes.  On the other hand, his VO2max, a measure of aerobic fitness, has not improved at all.  As Timmons already knew based on the blood test, Mosley is a non-responder.  Timmons sums up the experience with these words: “The truth about exercise is that it should be tailored to the individual.”  In Mosley’s case this means that he intends to continue the HIT routine, keep trying to increase his NEAT, and remember that “The chair is a killer.”