Wednesday, September 16, 2015

Marathon Training Update from Dr. Brandon Larkin: Diet, Exercise, and the Coca-Cola Conundrum #WorkoutWednesday

Last week, we talked about a runner’s (and by extension, any active person’s) propensity to overeat after a prolonged bout of exercise.  For me, it’s the Saturday long run that inspires gluttony.  And for me, and others, the reasons are numerous: a reward for a job well done, a misinterpretation of an acceptable amount of replacement calories (see: poor math skills), or simply insatiable hunger.

But as we discussed, pounding the donuts and ice cream all weekend after completion of a long run probably doesn’t make for the best nutrition strategy, especially if you are using running (or any exercise) as a method for losing weight.

So this begs the question: “What is the correct balance between diet and exercise for losing (or maintaining) weight?”

There is A LOT of controversy about the answer to this question.  Many think the rise in sugar and fat intake is the biggest cause of today’s obesity epidemic.  Others insist it’s the ever-increasing amount of time we spend being inactive every day. Which is more important, diet or exercise? Or is it both?

Thankfully, you just happen to be best buds with a well-read, intelligent, charming sports medicine physician. (Who, you ask? Really funny.  It’s me.)

So I’m going to fill you in on the secret.  The answer to this all-important question of health is this:

“It’s complicated.”

Most studies point to a combination of appropriate diet/calorie control with regular moderate-intensity exercise as the best strategy.  New research comes out all the time on this topic, and I like to keep abreast of the current thinking to counsel my patients (and you).

So I was particularly interested about a presentation at one of my national meetings this year about the Global Energy Balance Network.  This is a group of scientists who believe that the best intervention to fight the obesity epidemic is to promote exercise.  Activity, they believe, is the single most important predictor of who will actually keep weight off for good.  They contend that sedentary behavior sets the body’s metabolism at a different level than it would be if a person were an active exerciser.  That means that caloric balance (calories in = calories burned) is more effective in losing or maintaining weight in someone who exercises than it is in one who doesn’t. 

Put another way, you can eat more calories if you burn more calories by exercising regularly.  If you don’t exercise, you have to eat less food and be much more restrictive, and this is harder to maintain in the long term. 

It really isn’t that simple, they say.  While exercise is super important, lots of other variables go into it, like genetics, body physiology, and behavioral factors.  Some of those you can control.  Some you can’t.

But here’s the thing.  I control one of those things a lot.  I exercise like crazy.  I’ve run a few marathons.  And the amount of miles I’ve logged and calories I’ve burned during training have never really resulted in any weight loss.  I got hungrier during training.  I reasoned that I deserved a reward for completing my long runs.  So I ate.  And ate big.  (See last week.)

I’ll burn close to 2000 calories on some of these runs.  But if I don’t watch what I eat, I can put that much and more back on by the time I’m pushing back from the table at lunchtime.

So the “Exercise is King” argument seemed to fly in the face of my reality.  I only began to lose weight when I became very aware of the caloric content of what I put down the hatch.  Only once I realized that my previous diet had me taking in vastly more than I was burning did I start to trim down.  Even with this knowledge, I wasn’t militant.  I ate gluten.  And ice cream.  And a little scotch.  But I paid attention to how much I was eating and was careful not to throw my energy balance out of whack.  And it worked.

Maybe I’m not like everyone else.  Who am I to argue with the science of the Global Energy Balance Network?  I may just be special.

Turns out I’m not.  Last month, the New York Times published an article that exposed the major source of funding for the GEBN.  It was Coca-Cola.  Coke supported much of the research performed by the scientists I heard speak about the importance of exercise.  And it was Coke’s dollars that might have biased the opinion that what you eat isn’t as important as how much you move. 

So maybe diet has something to do with it, too.

The answer lies somewhere in the middle.  Both are crucial.  I don’t think a researcher’s funding source automatically negates their findings.  Exercise is incredibly important.  It makes weight loss easier by burning calories and revving metabolism.  Even if Coca-Cola pushes that belief.  Doesn’t make it wrong.  You just can’t forget the other side.

In my opinion, based on personal experience and professional training, the best strategy for weight control, as with most things, is moderation.  Despite vigorous preaching about the dangers of what we eat, it’s pretty likely that there is no one single evil nutrient.  You can probably eat fat.  And (gasp!) carbs. You probably want to stay away from foods and drinks with high refined sugar contents, like donuts.  And Coke.

But then again, one Coke or two donuts probably won’t make or break you.  You just have practice than magical dogma: moderation.  Just don’t let two donuts become four because you ran ten miles this morning.

And you know what? Get up and move!  Walk around a little.  Run a marathon. Or a half.  Or a mile.  Flip the TV off.  Hey, Facebook will be there when you get back.

So after you run this weekend, sit back and be satisfied with a job well done.  Heck, have a Coke and a smile.  Just make sure you take that 12-ounce calorie bomb into account with your choices later on.


  1. I am also going through the same situation as I am loosing weight but I am just decreasing my intake of calories to decrease that because I have a very inactive day. Due to this reason, I am having pain in my legs and have to go to chiropractor to get rid of my pain. I am sure that he is also going to give me some diet plain as well to get rrid of pain.