Friday, May 4, 2012

Losing weight

VO2 max isn't a dead-accurate predictor of running ability; there's a lot more to running than a single number. But it's also true that everything else being equal, if you improve your VO2 max, you will probably improve your running ability. Unfortunately, VO2 max is thought to be relatively inflexible.

In my case, I might have an out, as I mentioned in a post on Science-Based Running:
One “easy” way to improve your VO2 max is to lose weight. As long as you’re only losing fat and not muscle mass, if you maintain fitness, your VO2 max should improve. This is because it is a measurement of oxygen volume per kilogram of body weight per minute. If you decrease body weight and everything else stays the same, VO2 max will increase. 
For the last several months my weight has been hovering around 190, giving me a BMI of 25.1, which is considered borderline overweight. That same calculator suggests that to be in the middle of "normal" BMI range, 21.7, I would have to lose 25.5 pounds and get down to 165.5 pounds.

I'm pretty sure that's not a realistic weight for me. My body fat percentage is about 16.7, giving me about 32 pounds of fat. If I lost 25.5 pounds, assuming it was all fat, I'd have just 6.5 pounds of fat, or 3.9 percent, which is probably unhealthy. The 99th percentile of body fat for men my age is 6.7 percent. That's right, a "normal" BMI is unhealthy. This is a pretty dramatic demonstration of the limitations of BMI for assessing fitness. I recall reading that Michael Jordan in his prime was "overweight" according to BMI.

A more realistic weight loss goal would probably be around 15 pounds, which would put me at 175 pounds and 17 pounds of fat, or roughly 10 percent, which is between the 95th and 99th percentile for my age group.

At that weight, assuming everything else stays the same, my VO2 max should increase from 56.1 to 60.9. That represents potentially more than a minute off of a 5K time, and 10 minutes off of a marathon time -- no small potatoes!

Naturally I will want to improve my fitness at the same time, but it's startling to realize that without improving fitness I could be a sub-18-minute 5Ker.

Unfortunately, losing weight does not come easy for me. Many people assume that I lost weight "automatically" when I started training for a marathon. The truth is, even when I'm running 70 miles a week, I still have to watch what I eat. Yes, I can eat a little more during hard training weeks, but even then, if I eat as much as I want, I will gain weight.

For me, the key to losing weight is minimizing snacking and limiting my portions at mealtime. Easier said than done. I work at home, so I have infinite access to the kitchen. I have a set routine of 4 (yes, 4) healthy snacks a day: A granola bar, yogurt, an apple, and a banana. I try to distribute these over the course of the day. I have a salad for lunch. At dinner I try to prepare meals that don't give the option of infinite refills. Spaghetti is bad, a small hamburger is surprisingly good (especially when paired with veggies or a salad). I avoid the temptation to snack before bedtime; I've tried to make a virtue out of going to bed hungry.

In fact, there is a lot of time during the day when I am hungry. Sometimes I will actually be a little lightheaded. In these cases I try to drink water or other liquids instead of eating. Then slowly, the weight starts to come off. The plan is to try to lose 5 pounds a month over the summer: May, June, July. If I'm successful, on August 1 I should be under 175 pounds. I'll be updating you here.

Most recent weigh in -- 187. Goal for the end of May: 185.

Details of yesterday's workout are below.

Ran the trails with DART in the afternoon. Ron Garsik kept me honest in the heat and I kept up the pace to the end.


  1. omg - i certainly feel your pain. I could have written the same blog (well almost, I can't say that I'm hungry most of the day) before becoming a "marathoner", I remember thinking "if I trained and ran marathons I would be able to eat whatever and I will stay thin." so not true (even at 40-70 miles per wk- and that's just WRONG!) It's a constant battle....urgh!

    I have decided that strength training helps a lot, although I suspect if I did that, as my main workout (like running), the body would adapt to that too.

  2. I have heard the same thing about strength training. For now, I'm resisting doing that because I really don't enjoy it, but I have pulled out an old Pilates video and I'm starting that up again. Hoping PIlates, plus some push-ups and planks, will be sufficient to stimulate some fat-burning.

  3. I can sympathize with the weight loss "issue." Keep in mind that the scale doesn't tell the whole story (any more than BMI does). Percent body fat (and or muscle mass) is far more important - but much harder to measure, alas! I have a trainer who is 60 years old, and a former body builder. He looks AMAZING and he has taught me a few things... Such as: "Body builders don't care what they weigh, they care what they look like." The truth is, I weigh 9 lbs more than I did 10 months ago, but my clothes fit exactly the same (maybe the waist is even looser). I've been doing aggressive strength training for many months now and everyone thinks I look MUCH better/stronger. Also, my running has actually improved for short distances (haven't tried long). I would strongly encourage you (pun intended) to add strength training to your regimen - 3x/wk if possible. Find a pal to do it with and it can even be fun! Plus, who doesn't like a guy with a little meat on his bones? ;-) --Dr. Val