The Truth About Exercise?

Tennis ShoesRecently I watched a program on PBS called The Truth About Exercise with Michael Mosley that addressed some surprising new research and challenged many of the things I had ever heard about working out.  Y’all, I hate exercising.  I will do whatever I can to avoid it, especially when life gets busy… or I’m tired, or stressed, or lazy, or just having too much fun to not have fun.  If you’re anything like me, I think you’ll find some hope in what this program had to say.

There is obviously a relationship between weight loss and exercise – we’ve all seen the inspiring stories about people who started crossfit or trained for a race and shed the pounds.  Then, we also hear that exercise is not really sustainable for losing weight, that it’s about what we eat and maintaining a healthy diet.  And, truly, eating right does work for everyone. But, there are other benefits of exercise to consider as well:

  • “Exercise gives you endorphins. Endorphins make you happy…” – Elle Woods.
  • Lowers blood pressure and risks of stoke & heart attack
  • Lowers your risk of diabetes. This program showed how 90 minutes of walking the night before a terrible-for-you breakfast reduced fat deposits from that meal by a third. The enzymes (lipo protien lipase) released during exercise stay in the system and make fat go to be burned by muscles rather than into our fat stores. This prevents damage to our blood vessels and also the deep fat in our organs (fat around our waist) that’s really dangerous.

Let’s be honest, though, for all that hard work, most of us are really looking to lose weight.  Unfortunately, it does not give many the fat burn they really want.  In fact, it has now been scientifically proven that people respond very differently to the same amount and type of exercise.  15% of the population see huge physical benefits from exercise, while 20% of the population see absolutely no change.  Those 20% are called non-responders and, unfortunately, it’s genetic.  Then there are the other 65% who are somewhere in the middle of that range.  Exercise is not one size fits all… exercising more may not help you, and that, combined with our busy lives, is certainly not motivating us to get to the gym.

Professor Jamie Timmons, University of Birmingham (UK), performed clinical studies of non-responders and set out to find a form of exercise that helps everyone and is sustainable enough to fit into our busy lives.  They used two main tests to measure the health benefits – 1. Insulin Sensitivity (Insulin removes sugar from the blood and controls fat – I discussed this in detail a few weeks back; sensitivity is a measure of how quickly it works) and 2. VO2 Max (how much oxygen your body is able to use, which is a huge indicator of the future health of your cardiovascular system).  Studies suggest that short spurts of highly intense exercise is what can improve these two: 20 seconds of the most intense exercise you can handle, followed by period of rest, repeated twice.  Do that three days a week.  This can be cycling as fast as you can on a stationary bike or sprinting down the street.

How can this possibly work?  That crazy intense form of exercise breaks down the glycogen stores in the muscle and that’s the key signal from the muscles to say “I need more glucose to burn, NOW!” to the blood.  Unlike walking or jogging, where you are only activating 20-30% of your muscles, this intense exercise is activating 70-80% of your muscles, which creates a much larger sink in glucose, causing your body to get more sugar out of the blood to burn.  In fact, they saw results in these two crucial areas in just 2 weeks.

After the show’s host, Michael Mosley, participated in 4 weeks of this protocol, they tested his insulin sensitivity and VO2 Max. He had an overall improvement of insulin sensitivity of 23%, which is remarkable, but in line with what the clinical studies are proving.  Michael also learned that his aerobic activity did not increase at all which proved (along with a genetic test) that he is a non-responder to exercise.

A couple other interesting things I learned from the program:

  • Most of us spend 12 hours a day sitting and not moving.  Being active increases your metabolic rate. Moving throughout the day is how we were designed, so that’s obviously best for our bodies.  Dr James Levine, Mayo Clinic, an obesity expert, says that the best way to burn fat is to increase your NEAT – Non-Exercise Activity Thermogenesis.  No need to sweat, but make a more conscious effort to constantly move.  Our bodies idle when we sit for an hour, gunk builds up: blood sugar and fat elevate. In order to keep the fuels moving through your system, you need to be moving every hour, not just exercise a couple times per week.
  • We may feel like our muscles are what get tired and that’s why exercise exhausts us, but, actually, it may be our brain.  Michael Mosley did a test in a low oxygen chamber and he got tired very fast as soon as his brain realized that he wasn’t getting enough oxygen.  This measured how hard he thinks he can push his muscles. But when probes were applied to his head, putting pressure on the part of the brain controlling his legs, it allowed him to push himself to keep exercising. Our subconscious brain is protecting itself – it triggers a shutdown before you are actually in “danger.” But, your brain can learn that this activity is not threatening which is why it begins to feel easier after training.

If you want to learn more, I highly recommend watching it for yourself here.

Do you think these experts discovered the truth about exercise?  Could you commit to this 3-minute-a-week exercise routine?  Who wants to try it with me to see if it works?

Why We Get Fat…

“We get fat, our physicians tell us, because we eat too much and/or move too little, and so the cure is to do the opposite.” – Michael Pollan, In Defense of Food

When my husband and I are planning a date night out to a really great restaurant and want to eat as much delicious food as possible, we often eat a light lunch or do something active to make ourselves hungrier for the big meal. But wait, that’s also what I’m told to do to lose weight…. Something’s wrong with this reasoning.

In his book, Why We Get Fat: And What to Do About It, Gary Taubes tackles this cultural mindset of “calories in, calories out,” turning it on it’s head and calling into question a principle we’ve always held to be true. It’s a fascinating read, with lots of really compelling cultural case studies and the scientific details in layman’s terms that help you to understand his argument.   I have a bad habit of reading the Appendix of a book first and will admit that I was disappointed with some of the diet recommendations he makes – in particular, okaying alternative sweeteners like Splenda and Nutrasweet and diet soda; but, I had a long plane flight ahead of me and nothing else to read so I kept on.  I’m glad I endured because there are definitely some great nuggets of information I got from this book:
 Obesity has become an epidemic.  1 in every 3 Americans are considered obese compared to only 1 in 9 fifty years ago. I’ll admit that I used to think that most people get fat by simply being lazy and/or eating too much junk food.  But, a case study of many areas of poverty shows that there are many who are malnourished (less calories in), work manual labor (more calories out), and who are still obese or overweight.  And in research studies, hormone-manipulated rats proved that they immediately began to overeat, become sedentary and quickly grew obese; even when completely deprived of food, forced to diet or forced to exercise, the rats retained their fat while their organs deteriorated.  There must be some other determining factor than being slothful and gluttonous…. it seems more to do with genes and hormones than simply overeating.  The answer lies within the fundamental definition of obesity- “a disorder of excess fat accumulation.”

Taubes relates fat tissue to a wallet: “you’re always putting fat into it and always taking fat out.”  But only certain forms of fat can go in and out, while others go in and stay. When fatty acids enter a fat cell, they join up with a glycerol molecule and two other fatty acids to become a triglyceride. Triglycerides are too big to go back out of the cell membrane, so they stay captive until they can be disassembled.  The hormone that works to create triglycerides is insulin.  Insulin works through the LPL enzyme and the HSL enzyme.  The LPL enzyme sends fatty acids into the cells for energy. When we exercise, LPLs trigger the release of fat from fat tissue and send those into muscle cells to burn off.  (As soon as we stop, though, LPLs work to help fat cells regain that fatty fuel, which is why Taubes claims exercise doesn’t make us lose fat, just gains us muscle.) The rest of the time, insulin triggers LPLs to send fatty acids into fat cells and tells muscle cells to burn blood sugar rather than fatty acids, so insulin basically keeps these fatty acids in your fat cells.  Insulin also suppresses the HSL enzyme, which is the enzyme that breaks down the triglycerides into fatty acids to move out of the fat cells.  And when our fat cells get full, insulin creates new ones… working constantly to make us fatter… it’s no wonder that so many diabetics that start insulin therapy gain so much weight.  Further, every other hormone in our body works to release fat from our fat tissues so that it can provide fuel for what it needs to do, but “insulin trumps the effects of other hormones.”  And as we get fatter, our demand for more fuel increases, which causes our appetite (especially for carbs) to increase. So, to lose fat, we must lower our insulin levels.  The way to do that is to diminish the cause for insulin secretion – carbohydrates.

Okay, but I eat healthy and I still struggle to lose weight, while I watch others eat fast food daily and stay super slim… frustrating, isn’t it? One reason is that “some people will secrete more insulin than others, and those who do are likely to put on more fat and have less energy.”  The other reason is that many of us have become insulin resistant. Eventually, your cells stop wanting all the glucose you’re putting in your body, and they start making insulin’s job harder to get it out of the bloodstream, which results in you secreting even more of it.  Everyone’s tissues react differently: if your muscle tissue is really sensitive to insulin, then you’ll use up more glucose in those cells, making you naturally lean, but if your fat cells are more sensitive, then glucose will go there instead and you’ll become overweight. And as we age, our muscles naturally become more resistant to insulin, which explains why we tend to get fatter as we get older.  Most importantly, this doesn’t just affect us, but our children too.. “the higher the level of a mother’s blood sugar, the more glucose her child gets in her womb” and therefore will be born with more fat and predisposition to be insulin resistant.

At this point in the book, he had my attention… is this resounding with you as well?  Tune in tomorrow for And What To Do About It.