Sunday, February 26, 2012

Why Body Weight Fluctuates: Water Gain/Loss Explained

I'm starting to become a fitness geek and recently have been reading everything about how the body works.  I've been reading about how the body stores and uses energy and stumbled on the answer to why body weight fluctuates so much.

When starting to diet, most people lose several pounds quickly then level off.  The weight lost is often described as water weight.  The water weight can be caused by a reduction of the amount of glycogen, an energy reserve, in your body.  It can also be caused by less water in your tissue caused by a reduction in the amount of salt you consume--a byproduct of healthier eating.

Both can cause your weight to fluctuate several pounds in a day.  It's important to understand how these factors affect your weight so you can focus on what is important:  Losing body fat, and not just body weight.  Note that there may be other causes for water gain such as medication and medical and conditions and hormones which I won't go into here.

Water Retention from Salt
Water retention from salt is easiest to explain.  In summary, your body uses electrical impulses to function.  Electrical impulses are made possible by a balance of sodium, potassium and water.  If you consume too much salt, the kidneys put more water into your system to keep the sodium in balance.  The extra water is absorbed by the body through osmosis and you gain weight.  According to Water-Retention.Net, salt based water loss is usually no more than 2 pounds.  Read this article, How Salt Affects Your Weight, for more information.

Glycogen and Water Retention
What glycogen does and it's role in water loss is more important to understand and more difficult to explain.  In short, carbohydrates are turned into glycogen and stored in the muscles and liver.  Think of this as your primary fuel tank.  If you run out of glycogen, your body needs an alternative source of carbohydrates (fuel) so it turns protein (muscle) into carbohydrates.  If your glycogen levels are full and you eat more, it turns the extra carbohydrates into fat.

When full, the body stores about 400 grams of glycogen worth about 1600 calories of energy (variables include amount of muscle mass and individual physiological differences).  Each gram of glycogen needs 3-4 grams of water for storage.  That equals 1600 grams of water stored in glycogen, or 64 ounces (half a gallon) weighing 4.15 pounds.

If you cut back on your carbohydrate intake to create a calorie deficit, your body isn't able to replenish the glycogen as it's used.  The result is weight loss from the loss of glycogen, not fat.  If you have a glycogen deficit then replenish from a large meal, the glycogen is replaced resulting in a weight gain from additional glycogen, not fat.  The result is that one 2000 calorie meal can theoretically cause you to put on 4 pounds of weight overnight.

How I Use This Knowledge
I know one pound of fat represents 3500 calories, so I would have had to burn that many fat calories to lose a pound of fat, very unlikely in a day unless I went on an extreme ride (8+ hours).  Conversely I'd have to eat over 6000 calories in a day (something like 3 large pizzas) to gain a pound of fat, again very unlikely.  

I weigh myself every morning to see how my weight has fluctuated.  If I've lost of a pound or more overnight, I know most likely its water so my glycogen stores are down.  I don't worry as much about calories for the next day.  My "gas tank" is getting empty so I should refill it, without overfilling it (producing fat).  If I plan to ride or do something else physical, I'll intentionally eat more (carbo load) to make sure I have energy.

If I've gained a pound or more overnight or haven't exercised for a couple of days, I know to watch my calories more carefully.  My "gas tank" is getting full so I don't want to overfill it and add to my fat stores so I'll stay closer to my calorie budget and not worry if I go below it.

This may also explain why many smaller meals are better for you than one or two large meals (although I haven't researched it yet).  I think of smaller meals as a just-in-time carbohydrate delivery system for your body which minimizes the risk of overfilling and producing fat, or under filling and creating a situation where your body needs to burn lean muscle mass.

What are your thoughts and experiences?

Some Interesting Articles
Understanding Body Weight and Glycogen Depletion--Blogger Justin Owings describes the concept in more detail than I do.
The Fat Burning Mechanism--Glycogen Depletion--Glycogen depletion from the body builder's perspective.
Don't Burn Lean Muscle Tissue--What happens if you fully deplete your glycogen stores, burning lean muscle, and why I don't want to empty my glycogen stores.
Starvation Response--More on what happens to your body if you don't have enough carbohydrate based energy.

Do you have any interesting links related to this topic?

Saturday, February 25, 2012

How I Lost 10 Pounds in 1 Month

I'm nearing the end of my first month of my healthy lifestyle and I'm in my fifth month of bike commuting.  I feel really good!  Here are some tangible measures of my increased fitness:
  • Weight:  I've lost ten pounds since January 30.  More importantly, my percent body fat is down to 22.5% (from 24%).  If you do the math, that's about 5.5 pounds of fat loss.  Assuming 4 pounds or more is from water loss, I'm achieving my goal of losing mostly fat and not lean body mass.
  • Resting Heart Rate:  My resting heart rate is down almost ten beats per minute since Christmas.  
  • How I Look:  I've lost 2 notches in my belt, and I feel thinner.
What did I do to lose 10 pounds in a month?  Nothing more than eating fewer calories than I take in.  To make sure I really eat fewer, I track my calorie intake and expenditure using LoseIt! (there are other tools available, Google "calorie tracking app").  It's very easy to use with iPhone and Android apps and a database with nutritional information for thousands of ingredients, restaurant, and supermarket foods.

Based on my age, weight, and activity level (before exercise), LoseIt! estimates that I use about 2700 calories on an average day (see this article on the Basal Metabolic Rate from Wikipedia).  Based on this, if I eat more than 2700 calories, I gain weight.  Less and I lose.  I told the LoseIt! app I want to lose 1.5 pounds per week and it established a daily budget of 2,053 calories.

Using today as an example, I was planning a long bicycle ride so I knew I could essentially eat what I wanted.  Some insights I've gained by tracking what I eat:

  1. It's hard for me to eat less than 30g of saturated fat each day without making choices.  I have to work on this.
  2. A McDonald's Quarter Pounder with Cheese value meal (see my lunch) really isn't good for you.  You can be told something is bad for you, but until you see it, you don't always comprehend.  This meal gave me 1200 calories and nearly half of my saturated fat for the day.  I would not have eaten this if I wasn't planning to ride.
  3. It's easy to add a lot of calories from soft drinks, especially with free refills and cheap large size drinks.  I normally drink iced tea so this was a treat made possible by my bicycle ride.
  4. I used to drink A LOT of skim milk (as many as 4 or 5 glasses with a meal).  Now I try to limit myself to one or two.  Some days I'm sure I consumed over 1000 calories from skim milk alone!
  5. I consume too much sodium.  My blood pressure is good, but still something to watch.
  6. I might have eaten 4 or 5 servings of something without thinking about it.  Now I try to practice proper portion control
  7. If I didn't ride regularly, I would have to reduce my calorie intake A LOT more to lose the same amount of fat.

 Below is my daily summary for today.  Do you know what your typical day looks like nutritionally?

Daily Summary for 2012 February 25
Export to spreadsheet
Daily Calories
Daily calorie budget
Food calories consumed
Exercise calories burned
Net calories so far today
I can eat 97 more calories today
Nutrient Calories
Saturated Fat31.4g
Meal Calories
Today's Log
Breakfast: 619
Cereal, Cheerios, Multi Grain
2 Cups
Milk, Nonfat/Skim, w/ Add Vit A & D
1 1/2 Cups
Doughnut, Raised, Choc Frosted
1 Each
Lunch: 1196
French Fries, Medium
1 Each
Cheeseburger, Quarter Pounder
1 Each
Soda, Cola
40 Fluid ounces
Dinner: 1251
Breaded Creme Brie and Apple Stuffed Chicken Breast
1 Serving
Beans, Green, Cut
1/2 Cup
Potatoes, Ckd In Skin, Peeled, Diced
1/2 Cup
Lunchmeat, Turkey Breast, Oven Rstd, Grand Champion
1/8 Pound
Lunchmeat, Ham, Baked, Home Style, Svg
1/4 Pound
Milk, Nonfat/Skim, w/ Add Vit A & D
2 Cups
Peanut Butter Honey Ball
2 Servings
Snacks: 648
Milk, Nonfat/Skim, w/ Add Vit A & D
1 1/2 Cups
Juice, Cranberry Acai Plus, 100% Juice
16 Fluid ounces
Nuts, Almonds, Whole
16 Each
Beer, Can/Btl, 12 Fl Oz
12 Fluid ounces
Exercise: 1757
14-15.9 mph, fast
2 Hours

Saturday, February 11, 2012

How I'll Be the Biggest Loser... losing 20 pounds.  

A few weeks ago some members of my family thought a fun way to provide weight loss support to each other and get ready for the summer swim-suit season would be to start a "Biggest Loser" style contest.  The premise is simple:  The competitor who loses the greatest percentage of body weight by June 1 is the "biggest loser" and winner of the competition.  To put some skin in the game, there is a $25 entry fee with the top 3 winners sharing the pot.

I'm tall, 6'4", and not obese, just out of shape.  My life-time heaviest and worst physical shape was a few years after college when I weighed nearly 230 pounds.  At my most fit in my late 20's I was close to 190.  I was working out at the YMCA 4 days per week and eating well.  Working out was easy then as the "Y" was 2 blocks from my Indianapolis apartment and I wasn't married with kids.

On January 30 I was 216 pounds with 24% body fat according to my electronic scale.  24% body fat is the high end of "average" percent body fat according to a Wikipedia article.  I realize electronic scales typically aren't that accurate so I plan to get a more accurate measure of my body fat.

My goal is to lose 20 pounds of fat bringing me to 195 pounds and 16% body fat (assuming the starting 24% is accurate).  That will be 9.7% of my January weight.  I'm not worried about losing 20 pounds.  The challenge will be losing only body fat.  I fully expect to have to add weight training, most likely bodyweight exercises, to avoid losing and even building muscle.

I found a very interesting blog written by New York marketing consultant Peter Shankman called A Year To Ten Percent.  The blog describes his attempt to reach ten percent body fat in a year.  Peter is a triathlete who busted his butt to try to reach his goal.  He dropped 30 pounds of fat and gained over 10 pounds of muscle, ending up at under 15% body fat.  My goals aren't as aggressive as his, but a quote from his blog describes very well what I'll be accomplishing and hope to share through this blog:
This isn't a challenge with an end-date. This is about learning to eat healthy, make better choices, not deprive myself of everything, and still lose the weight, get the abs, and be happy.
We'll see if I have the 165+ pounds of lean body mass I need to give me a fighting chance at 195 pounds and 16% body fat.

What's It Like Commuting by Bike in Chicago?

First, some info on me.  I'm new to riding to work, starting in October riding to work once a week.  Now I'm not satisfied if I don't ride at least 3 days a week.  I live in the Sheridan Park neighborhood of Chicago (about a mile north of Wrigley Field) and work in Michigan Plaza (part of the Illinois Center) in downtown Chicago.  My commute is 8 miles one way.  I have several options for getting to work:  Drive, public transportation (bus or train) and cycling.  My favorite is cycling.

A typical bicycle to work morning:  Shower at home and put on riding clothes (casual clothes for me), ride 40 minutes and arrive at work, lock up my bike in my building's parking garage, change in my office's locker room, and start work less than an hour after I left home.  How does it compare to my other options?  Only 10-15 minutes longer than public transportation and 20-30 minutes longer than driving.

The ride home in the evening is the opposite:  Change clothes at work, ride, arrive home.

Advantages of Commuting by Bike
I can't believe it took me so long to start based on how much I enjoy it.  Below are some of the reasons I like it:
  • It's fun!  I really like riding my bicycle.
  • Time savings:  Commute time is dual purpose, transportation and exercise.  I get an hour and a half of cardiovascular exercise for a 10 minute time investment.  I'd have to spend nearly 2 hours a day outside of my busy schedule to otherwise get the same workout, not easy with family and other responsibilities. 
  • Being outdoors:  Most of my commute is on Chicago's Lake Front Trail which runs along the lake front.  I've watched the sun rise over Lake Michigan in the morning, a full moon rise over Lake Michigan in the evening, and seen many of the Lake's moods.  Occasionally it's reminded me of sailing (see my sailing blog, Sail Donnybrook).
  • A feeling of accomplishment:  It feels great to arrive at work by bike.  I feel like I've accomplished something instead of being frustrated by traffic.  It also gives me something to look forward to when leaving work--a bike ride instead of a grueling commute.
  • Money savings:  I save $4.50 a day over public transportation and $16+ day over driving (parking plus gas).  My bike will be paid for in savings after 50 days compared to public transportation and less than 13 days compared to driving.
Challenges of Commuting by Bike
Part of the reason it took me so long to actual start commuting is I focused too much on the challenges.  They were easy to overcome once I decided I really wanted to commute by bike.
  • Time.  I drop my boys off at school at a set time.  I have flexibility on when I start work, however there are days the extra 10-15 minutes can make me late to a morning meeting.  This is one reason I don't ride every day.
  • Weather.  This year's mild winter has made riding a lot easier.  There were still several days I chose not to ride due to weather.  They include:
    • Snow or ice.  Many people ride in the ice and snow (see the Bike Winter site) .  I've gone out in snow for practice, but haven't commuted while snow is falling.  Within a day or two of a snow, however, the roads and paths are generally clear enough to ride (with caution due to icy spots). 
    • Rain.  Snow doesn't bother me as much as cold rain.  Rain should be less of a deterent in the summer.
    • Cold.  I've commuted in as cold as 25 degrees.  Colder shouldn't bother me.  Heck, I've snow skied when the high for the day was sub zero.  I don't wear anything special, jeans, t-shirt under a sweatshirt, and my North Face outer shell.  The difference between 40 and 35 degrees is I wear thicker gloves.  Between 35 and 30 degrees I wear ear warmers.  Between 30 degrees and 25 degrees I wear thicker socks.  Colder than 25 degrees and I might add a liner to my jacket, something to cover my face, and possible long underwear to keep my legs warm.  The body generates a lot of heat so I haven't yet been cold on my ride.
    • Wind.  A head wind can really slow you down, especially on a bike like my hybrid where I'm sitting upright.  During the worst wind day (a 30+ MPH head wind) my bike speed was down to 6 MPH.  With no wind I can comfortably ride about 14 MPH.  A tail wind can help as much as a headwind can hurt.
  • Sweat.  I was worried about sweating and needing to shower at work (adding additional time), but the reality I found is I sweat very little at the pace I ride.  I wear a heart monitor (Polar RS300X) and I keep my heart under 78% of max, which is a light enough workout to carry on a conversation.  I'll write more about effort and heart rate in a future article.
Why It's Easy For Me
It seems I have it easier than others commuting by bicycle.  Here are some of the factors:
  • Proximity to work.  For me, 8 miles takes about as long as public transportation.  A longer ride will start to eat into the time savings.  The time should continue to decrease as my body gets more efficient--I've decreased my average ride time by 5 minutes when I started.  I've talking to people who regularly commute 12+ miles, and one person who commutes 19+ miles one way.  
  • Proximity to the Lake Front Trail.  I only ride 5 minutes on city streets.  It's bike path the rest of the way to my office meaning no stop lights to slow me down or crazy automobile drivers to scare me.  Summer, I'm sure, will bring another set of challenges due to the crowds.
  • Availability of a locker room at work.  Having a locker room to change makes it easy.  I also have access to showers if I find I need it in the summer.  I changed in the men's room before I got locker room access so it's not needed, but a locker room makes changing easier.
  • A bike rack in the parking garage in my building.  My bike is very secure there.  I have no worries about leaving it over night if I can't ride home for any reason (i.e. weather, dinner meeting, etc).
Resources That Helped
I like to research and understand something before I try it.  The links below provided the best information on commuting by bike.
What are your bicycle commuting challenges?  Whatever they are I'm sure they can be overcome with some persistence and creativity.