Saturday, August 22, 2009

Fat As a Fuel For Runners? You Betcha!

The body depends on three macronutrients in order to maintain good health—Carbohydrates, Protein, and Fat. Most runners think of carbohydrates when they think of fueling the body. They think of protein when thinking of rebuilding muscle tissue. But when it comes to fat, most runners probably think they need to steer clear of it. WRONG! Now, just like most things, fat has its time and place. A runner definitely doesn't want to eat a sausage biscuit right before a race, but he/she does want to make sure fats (the good kinds) have been a part of his/her diet during training. (Although my friend did eat pasta with cream sauce and sausage the night before a marathon and set a PR. We'll just attribute that to an Iron Stomach and an Iron Will.)


For so many years fat has been the bad guy. "STAY AWAY FROM IT!" is all we heard. Then came the day of fat-free this and fat-free that. Just like anything, if Americans can blame something for weight gain, they will, and they did and to excess. Instead of understanding that too much fat can be the culprit, many jumped on the bandwagon that all fat is bad. So fat has gotten a bad rap for a long time, but some fat is essential for survival.

Sited from The McKinley Health Center at the University of Illinois-Urbana-Champaigne, according to the Dietary Reference Intakes published by the USDA 20% - 35% of calories should come from fat. We need this amount of fat for:
Normal growth and development
Energy (fat is the most concentrated source of energy)
Absorbing certain vitamins (like vitamins A, D, E, K, and carotenoids)
Providing cushioning for the organs
Maintaining cell membranes
Providing taste, consistency, and stability to foods

There are three main types of fat—Saturated, Unsaturated, and Trans. Saturated fats are found in foods like meat, butter, lard, palm oil, coconut oil, and cocoa butter. Saturated fats remain hard at room temperature.

Unsaturated fats can be divided into two groups—Monounsaturated and Polyunsaturated. These fats tend to be healthier for you. Monounsaturated fats are found in foods such as nuts, avocados, olive oil, canola oil, peanut oil, corn oil, safflower oil, sunflower oil, and whole grain wheat. A good way to tell if something contains monounsaturated fat is that if it's put in the refrigerator it remains a liquid but becomes cloudy. Polyunsaturated fat is found in foods such as grain products, fish and sea food (herring, salmon, mackerel, and halibut), soybeans, and fish oil. Polyunsaturated fats remain a liquid and clear when put in the refrigerator. At least 2/3 of your fat intake should come from unsaturated fats.
Trans fats truly are the "bad guys." This type of fat is found in some prepackaged baked goods, snack foods, fried foods, and margarines. Hydrogenated or Partially Hydrogenated oil are the key terms to look for in the ingredients list when determining if something contains trans fats. This can be confusing though when you look at the fat content and don't see trans fats listed or see "0" beside trans fats, even though you see hydrogenated or partially hydrogenated oil listed in the ingredients. This is because if the food contains less than .5g of trans fat per serving, legally it can claim that it contains no trans fats. So, if you want to be 100% trans-fat free, be sure to read the ingredients list. Trans fats have been shown to increase your risk for heart disease by raising LDL cholesterol (the bad kind) and lowering HDL cholesterol (the good kind). Replacing saturated and trans fat in your diet with unsaturated fat has been shown to decrease the risk of developing heart disease.

Okay, so know you know just about everything this is to know about fat, you're probably wondering how and why is this important to runners? Good question. The biggest difference between carbohydrates and fat is that fat packs more power per punch. Technically speaking every gram of fat provides 9 calories (energy) vs. each gram of carbohydrates providing only 4 calories. Fat provides almost twice the energy. But unlike carbohydrates, a runner shouldn't "fat-load." Instead the runner needs to condition his/her body to make better use of the fat stores he/she already has.
Whether runners know it or not, they are using fat as a fuel in lower-intensity exercise (less than 70% max). However, running at this lower intensity over and over will not help with better utilization of fat as an energy source especially at increased speeds or later in an endurance run when you tend to get fatigued.
So, you may be wondering how to determine your VO2 Max and then how to increase it? The best way to determine your VO2Max is through a stress test. It used to be that stress tests were done mainly in a clinical setting, but now some running stores such as some of the Fleet Feet Sports stores are providing VO2 Max testing. But if you don't have access to such testing, the next best thing is to do a timed 1.5-mile run test on a treadmill or on a track. Run as fast as you can for 1.5miles (6 times around a track). Divide 428 by the minutes and add 3.5 to that number to calculate your VO2 Max.
3.5 + 483/time in minutes = VO2 Max

Example:
3.5 + 483/9.83 mins (9:50 converted all to minutes; just divide the seconds by 60 and add to the minutes)
3.5 + 49 = 52.5 VO2Max

Runner's World's Amby Burfoot has created the 5 Principles of VO2Max Training that are great in helping you on your way to increasing your VO2 Max and better utilizing your fat as energy.

5 Principles of Max VO2 Training
  1. Maximum oxygen uptake, or max VO2, is a scientific measurement of the amount of oxygen your body can deliver from your heart and use in your major exercising muscles. As you get fitter, your maximum oxygen uptake increases.
  2. All running increases your aerobic capacity, but the most efficient workouts for increasing it are those in which you run slightly faster than your 5-K race pace. For example, run 4 x 800 meters at 10 to 30 seconds per mile faster than your 5-K race pace. Jog for four to five minutes between repeats.
  3. You can also run aerobic-capacity workouts off the track by running hard and fast (but not all-out) for three to five minutes at a time. Jog for four to five minutes between repeats. You may also know this type of running as Fartleks.
  4. Do aerobic-capacity training only once a week, and skip it on a week when you have a race. Otherwise, you risk overtraining and increasing your fatigue rather than your performance.
  5. After six weeks of max VO2 training, take a break from it for four weeks. Concentrate instead on longer, more relaxed runs.
Periodically check your VO2 Max by redoing the 1.5-minute test to see if your VO2 Max has increased. So now that you have the skinny on the fat as fuel, get out there and try it!

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5 comments:

Ted said...

EXCELLENT POST !!! This is so fascinating. You have given me quite an excellent information. I have always wanted to know my VO2 max. I have to give this a shot. There are no place near my home that does the test.

I guess my trip to Dunkin Donuts will have to cease.

Ted said...

One more question RunnerDude... since 2/3 of my fat intake should be focused on unsaturated food. Which one? the monounsaturated or the polyunsaturated?

RunnerDude said...

Hey Ted! Thanks for the feedback! Moderation is the key. Have that donut, but just once in a while. LOL!
As far as monounsaturated vs. polyunsaturated The American Heart Association says that there is not sufficient evidence that monounsaturated fat is better than polyunsaturated fat, or vice versa, in terms of effects on heart health. So, just eat a good amout of both and a little of the saturated and avoid altogether the trans. Hope this helps!

JLF said...

Great post, love the VO2 max info at the end. I am definitely guilty of ignoring fat intake and probably err on the low side regularly- time to break out the avocados!

-Jamye

RunnerDude said...

Hey Jayme! Same here man. I have gotten much better about eating more things like almonds and using olive oil. I do find myself reading a lot more labels and making better choices. Every little bit!