Tuesday, September 30, 2008

Are sports drinks a good idea?

Never assume that what you eat or drink is good for you. We cyclists blithely ride around with colorful sports drinks in our water bottles, and with good reason: Sports drinks are a great way to ensure that you are energized and able to get the most out of your workouts. But we are often unaware of the problems some of them may cause.

Want to know what to watch out for? Read on...

One important thing sports drinks should provide is energy (calories). Sugar is the most common ingredient sports drinks use for energy. It may be called sucrose, or lactose, or glucose, or fructose, or maltose, or maltodextrin, or dextrose, or amylopectin starches, or any one of a huge number of names. All are a great source of quick energy for your muscles. But be careful; sugars by themselves usually have very high "glycemic-index" (GI) values; this means that they cause a blood-sugar spike that will burn off pretty fast (leaving you tired later on), prevent your body from burning fat instead, and over time can even cause insulin resistance (as in diabetes!). Think you're immune to insulin problems just because you're a thin athlete? Think again.

Don't get me wrong; high-GI foods have their place, and I definitely feel my workouts are better when I consume high-GI foods. They are also very important for post-ride recovery so you can be ready for your next workout (especially if, like me, you ride twice a day). Just don't overdo it.

How do you know what's the right GI? Read on...

Some examples of sugars, and their GI values:

  • Fructose (24 GI)
  • Lactose (46 GI)
  • Honey (55 GI)
  • Sucrose (61 GI)
  • Glucose (93 GI)
  • Maltose (105 GI)

Not to "pick" on any specific brand of sports drink, but I have a big bucket of Cytomax Performance Drink right here that is mostly "amylopectin starches." Sounds fancy, but it's simply the major component of starch, e.g. wheat. It's also very high-GI. This is followed by maltodextrin, another very high-GI food (the same as maltose, actually). How about Hammer Heed? More maltodextrin. Gatorade Thirst Quencher? Glucose, sucrose and fructose. These are no higher-GI than other sports drinks, just typical.

By the way, carbohydrates are the only foods that raise GI. Proteins and fats are all zero (0) GI. Meat, eggs, lard, butter, etc. are all zero-GI, or very close to it.

What's also important to understand is the "glycemic load" (GL) of a given meal. This is the cumulative affect of the GI of each ingredient, and their quantities. For example, a high-GI food combined with a low-GI food will yield a moderate-GL meal. It's fun browsing a list of typical foods and their GLs. Kind of an eye-opener. Some examples of high-GL foods:

FOOD Serving size (grams) Glycemic load
Dates, dried 60 42
Lucozade®, original (sparkling glucose drink) 250 40
Macaroni and Cheese (Kraft) 180 32
Raisins 60 28
Spaghetti, white, boiled 20 min, average 180 27
Baked russet potato, average 150 26
Bagel, white, frozen 70 25
Vanilla cake made from packet mix with vanilla frosting (Betty Crocker) 111 24
Cranberry juice cocktail (Ocean Spray®) 250 24
Fruit Roll-Ups® 30 24
Fanta®, orange soft drink 250 23
Couscous, average 150 23
White rice, average 150 23
Quick cooking white basmati 150 23
Macaroni, average 180 23
Cream of Wheat™, Instant (Nabisco) 250 22
Pizza, plain baked dough, served with parmesan cheese and tomato sauce 100 22
Cornflakes™, average 30 21
Coco Pops™, average 30 20
Snickers Bar® 60 19

The traditional food of cyclists is things like pasta, bagels, bread, cookies... all high-GI (the GL is even higher, because we tend to eat huge mountains of the stuff!), and all able to induce insulin resistance and defeat your fat-control plans.

You don't have to give any of these foods up, but try to eat them in moderate amounts, and combine them with low-GI foods, like proteins, as much as possible. See that Snickers Bar up there? Surprised it's lower-GL than rice or macaroni? Well, it has protein from the peanuts that keep the GL lower... uh, and tons of fat that is also low-GI; that may not be the best way to lower the GL of a meal!!!

Contrast that with low-GL foods (meats etc. not included because they are all zero-GL):

FOOD Serving size (grams) Glycemic load
Hummus (chickpea salad dip) 30 0
Soy beans, average 150 1
Peanuts, average 50 1
Milk, full fat 250 3
Grapefruit 120 3
Cashews, salted 50 3
Green peas, average 80 3
Carrots, average 80 3
Tomato juice, canned 250 4
All-Bran™, average 30 4
Ice cream, premium 50 4
Milk, skim 250 4
Pear, average 120 4
Watermelon 120 4
Orange, average 120 5
Peach, average 120 5
Pear, canned in pear juice 120 5
Lentils, average 150 5
Pumpernickel bread 30 6
Apple, average 120 6

My favorite post-ride food is dried dates, which are at the top of the GL list, but I usually eat them with nuts (zero-GI) and follow them with a protein shake for a moderate-GL recovery meal. See? It's easy to eat smart!

Oh, back to sports drinks...

My favorite is Accelerade Advanced Sports Drink. Why? Because it "combines carbohydrate and protein in a patented 4:1 ratio." That means it's lower-GL than other sports drinks. No, they don't pay me to say that... I wish they would though.

On a personal note: I used to get the afternoon blahs all the time. You know; about 2:00 PM I'd be sitting at my desk, nodding off over my keyboard. Maybe that starchy sandwich I had for lunch was to blame? Or the starchy cereal I had for breakfast? When I started eating lower-GL meals that blah feeling went away and never came back. What a relief!

If you want to feel better, have more energy, be healthier and ride faster, be conscious of what you eat and how it affects you. That knowledge will help you in all areas of your life.

Monday, September 29, 2008

Update on my repaired carbon frame

I broke the frame of my fancy carbon-fiber Giant TCR C2 during the last lap of a race on Memorial Day. But Calfee, a local bike manufacturer that also offers frame repair services, managed to fix the crack. I was a bit skeptical, but I now have about 400 miles on the repaired frame, including a number of high-speed descents at 40 to 50 MPH, and it has performed great. So my verdict is in; repairing carbon-fiber frames is well worth a try!

Now I just have to get rid of some lingering soreness in my body from the hard crash.

Been busy!

I haven't posted anything in this blog for a month and a half... how unlike me! Well, I've just been too busy and not much of interest has happened either. Well, mostly:

I did enter two races; the San Ardo Road Race on August 23rd, and the Giro di San Francisco, on September 1st. I hit a pothole in the first, and got three, yes, 3, punctures! This happened about 10 minutes into the race, so I spent the next 2-1/2 hours just riding solo. At the Giro I flatted with 4 laps to go, just outside the 5-lap "free lap" rule, so, again, I just chased solo. Sigh.

Speaking of flat tires: This year I have flatted in four races. That's definitely a personal record! All of them involved Michelin Pro 3 Race tires... I have now retired them and will never buy these again. My favorite race tire is still the Vittoria Open Corsa Evo CX tire. Very smooth ride, ultra-low rolling resistance, and I've only flatted them once.

The 2008 season is winding down for me, and I missed a few races I wanted to try, but I will be racing some of the Low-Key Hillclimbs again this fall. Should be fun, and good training. Team Bicycle Trip almost won the series last year!