Tuesday, September 13, 2011

Is Alcohol a Body Buzzkill?


Is Alcohol A Body Buzz Kill?

In honor of the start of a new school year when it seems like partying is a higher priority than attending class and no Saturday is complete without tailgating, I figured I would touch on what alcohol consumption does to your body.

Alcohol is what’s known as a priority fuel which means when it’s consumed, regardless of other foods consumed; it will be burned and metabolized until it is cleared from the body.  Alcohol can also slow down your body’s ability to burn fat as fuel as well as carbohydrates and proteins.  A common misconception about alcohol is that when you consume alcohol in excess it will be stored as fat or converted to stored carbohydrates to be used later as an energy source.  As previously mentioned, it is a priority fuel, so the alcohol is going to be burned first and everything else consumed will be stored as fat or carbohydrates.  So when you combine your Friday night beer with the late night pizza, your body is going to spend the rest of the night burning off the alcohol while the pizza goes straight towards your freshmen fifteen or your winter insulation as the northerners like to call it.

Average Calorie Amount In Alcohol:
  • Light beer, 12 oz, 90 to 110 calories
  • Regular beer, 12 oz, 150 calories
  • Red wine, 5 oz, 120 to 150 calories
  • Rum or whiskey, 1.5 oz, 98 calories
  • Gin, 1.5 oz, 120 calories
  • Vodka, 1.5 oz, 98 calories
A gram of alcohol equals 7 calories and even though they are excess calories, alcohol does not have any minerals, vitamins, carbohydrates, fats or proteins associated with it.   This is only the case when alcohol is consumed straight.  A lot of the times alcohol is combined with a wide variety of ingredients which will in turn increase the calories amount of a drink.  The big ones to watch out for are Long Island Iced Teas, Fruity Margaritas and other frozen drinks which can often have a calorie amount of ~700 calories per drink!
Alcohol can also cause result in a number of health issues such as: inflammation of the stomach, pancreas, and intestines which can impair the digestion of food and absorption into blood.  Alcohol is metabolized within the liver which is why long term alcohol consumption often leads to liver damage.  However, this is only the case if alcohol is consumed in excess over an extended period of time. Everything is okay in moderation.

And after saying all of this, I figured this quote was fitting:
“Beer is proof that God loves us and wants us to be happy”
-          Benjamin Franklin

Monday, August 29, 2011

How Many Calories Do You Burn?

How Many Calories Am I Burning?

Resting Metabolic Rate (RMR) is the energy required to maintain the systems of the body and to regulate body temperature at rest.  RMR accounts for approximately 60-80% of total daily energy expenditure.  The remaining 20-40% of daily energy expenditure depends on your activity level throughout the day (which includes basic occupational activities as well as exercise and sport activities).

Factors that influence RMR:

Factor
Effect on RMR
Age
↓ 1-2% per decade
Weight
↑ RMR with ↑ weight
Fat Free Mass
↑ RMR with ↑ FFM (the more muscle the higher your RMR is)
Fat Mass
↑ RMR with ↑ Fat Mass
Sex
Typically higher in Males when compared to females
Body Temp
12% ↑RMR with each 1 degree C increase
Severe Dieting
↓ RMR
Overeating
↑RMR
Menstrual Cycle
↑ RMR slightly (especially during luteal phase)
Growth/Pregnancy
↑ RMR
Acute Exercise
↑ RMR (depends on intensity and duration of exercise)
Thyroid Levels
↑RMR w/ higher levels and ↓ RMR when levels are low
Adrenaline
↑ RMR
Alcohol
↑ RMR (acutely)
Smoking (Acute)
↑ RMR
Caffeine
200-400 mg can ↑ RMR 5-15%

 A quick and easy estimation of your daily calorie expenditure is to take your bodyweight in kilograms (divide your weight in lbs by 2.205) and times this number by 27.5 and this will equal roughly your daily calorie expenditure if you are sedentary.  This number will obviously increase if you are active whether it be occupational, training, or exercise.

Friday, August 5, 2011

Race Fuel


Runners, cyclists, and other endurance athletes are constantly looking for ways to improve their performance.  One of these ways is to use nutritional supplements to “boost” their energy and allow them to perform longer or harder before fatigue sets in.  Carbohydrates are the primary source of energy during exercise.  They can be stored in the liver and skeletal muscle as glycogen.  When exercise lasts longer than 60 minutes, glycogen stores begin to deplete. Without our number one supplier of energy during exercise fatigue will be soon to follow.  An easy way to help maintain carbohydrate levels, slow down the rate of glycogen depletion and aid in performance is to consume a carbohydrate/electrolyte solution.  Ideally this beverage should be 4-8% carbohydrate solution and you should try to consume 8-12 oz consumed every 10-15 min (around 30-60 grams of carbohydrates total).  This should help maintain carbohydrate levels within the body and help delay the onset of fatigue.  The beverage or food should be high in carbohydrate and well tolerated which can significantly boost the carbohydrate delivery to working muscles.  These sources of carbohydrates can include: sports beverages, crackers, bananas, carbohydrate gels, or bread to help supplement the body with additional sources of carbohydrates during exercise.

Another important, and often overlooked, ergogenic aid during endurance events is water.  During exercise in the heat, sweat rates of up to 1.5-2 L/hr have been reported. This can quickly lead to dehydration and ultimately a drop in performance.   Every 1% loss of your body weight as sweat, results in an increased heart rate of 7 beats per minute which can put additional stress on the cardiovascular system during exercise.  Therefore the number one priority during long distance events (especially in the heat) should be hydration.

A number of studies have also shown that caffeine ingestion can significantly increase fat mobilization (up to 18%) in the blood and allow it to be burned as fuel.  This allows carbohydrate stores to last longer and essentially “spare glucose” which can also delay the onset of fatigue.  Studies have shown increases of up to 20% in performance following caffeine ingestion.  Doses of 3 to 9 mg per kg of bodyweight or a total of 250mg have shown to be effective.

In summary, make sure you are consuming enough fluids and carbohydrates during bouts of long exercise.  Also, the addition of caffeine may help with sparing glucose and allow you to last longer before fatigue kicks in.

Tuesday, August 2, 2011

Nutrient Timing



It has long been accepted that exercise, specifically resistance training, is the primary way to increase muscle mass. However, an often-overlooked component of this process is the importance of nutrition and even more importantly, the timing of nutrients. Without the proper combination of nutrients, timing and exercise, one may not reach full potential. Before a workout, it is important to eat a well-balanced meal and consume plenty of fluids in order for energy stores to be full and ready for utilization. Ideally, this meal should be consumed 2-4 hrs before exercise and consist of 200-300g of carbohydrates, 30-40g of protein, and roughly 16 oz of water. Meals should also be low in fat and consist of familiar foods to promote gastric emptying and minimize discomfort. In addition, meals should consist of low glycemic index foods to prevent a rapid spike in blood sugar and insulin levels and provide a slower rise in blood sugar, resulting in longer lasting energy. During bouts of resistance exercise averaging an hour, nutritional supplementation is not as important as it is during long-duration endurance exercise because energy supplies are not. Therefore, proper hydration becomes the main focus during bouts of resistance training. Consuming 6-8 oz every 10 to 15 min should be sufficient to maintain proper hydration.

 Following exercise, nutrition should be the number-one priority to maximize muscle gains. There is an “anabolic window” of opportunity when the body is primed for muscle growth to occur if the proper nutrients are present. Following resistance exercise, the rates of protein synthesis and breakdown are elevated as a result of the stress placed on the muscles during the workout. If proper nutrients are not supplied to the muscle, muscle tissue will continue to be broken down without the desired increases in muscle synthesis. This is why post-exercise nutrition plays such a vital role. Carbohydrates and proteins are equally important because proteins provide the backbone for the synthesis of new muscle and carbohydrates replenish energy stores and increase insulin levels, which aids in the transport of nutrients into the muscle. Ideally a post-workout snack should be consumed within 30 minutes after exercise followed by a larger meal 2 hours later. The post-workout snack should consist of carbohydrates and protein in a 3:1 ratio. This should equate to about 1.5 g/kg of body weight for carbohydrates and .5 g/ kg for protein. In this case, the carbohydrates should be high glycemic index foods to promote a rapid rise in blood sugar and insulin, which will assist in the influx of nutrients into the muscle. Proper re-hydration should also be considered post-workout to compensate for any fluids lost during. Again, it is imperative that proper nutrient intake and timing be included in any training program to maximize results and help achieve one’s potential.

For further readings related to this topic:
  • “International Society of Sports Nutrition position stand: Nutrient timing.”
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2575187/
  •  “Effects of Supplement Timing and Resistance Exercise on Skeletal Muscle Hypertrophy.”
Medicine & Science in Sports & Exercise: November 2006 - Volume 38 - Issue 11 - pp 1918-1925
 

Sunday, July 31, 2011

Shed pounds with a protein shake?

It seems as though high protein diets and protein supplements have received a stereotype that they are solely for athletes, bodybuilders, or people looking to “bulk up.” In reality, everyone can benefit from a high protein diet, especially those interested in weight loss….That’s right, I said weight loss! I don’t know how many times I’ve recommended protein shakes to female clients and they look at me with a “you must be crazy look.” It seems as though in their minds they automatically associate protein shakes with bulking up or getting huge.  I reassure them that you won’t get “huge” by simply consuming a protein shake after you exercise or randomly throughout the day (if only it were that easy!).

Our lab (Exercise & Sports Nutrition Lab at Texas A&M University) has continually shown that a high protein diet when combined with a resistance training program is the most successful way to lose weight.  First of all, I should clarify that when I say a high protein diet it doesn’t mean that you should consume extra calories in the form of protein.  What it means, is that a higher proportion of your daily calories should be coming from protein (~55-60% of your daily calories).   

The theory behind a high protein diet is that it will help you maintain your muscle mass which is an active tissue that continually burns calories.  Otherwise, you will see people who lose both muscle and fat during a weight loss program which in turn lowers their daily energy expenditure and makes it harder to lose weight.  Also, it's important to remember that in order to lose weight, you will need to lower your calorie consumption or at least make sure that you are burning more than you are consuming. 

This type of weight loss program (a high protein diet) coincides nicely with a resistance training exercise program (specifically high intensity circuit styles of training) because it will actually add muscle mass which again will increase your daily energy expenditure (boost your metabolism). But again, don’t worry because this doesn’t mean you are going to get huge.  So in conclusion, don’t be afraid to grab that protein shake!

Wednesday, July 27, 2011

BMI is NOT TMI


BMI vs. Body Fat Percent

Ok, this is something that’s bothered me for a while and I just wanted to clear the air a bit.  The terms body mass index (BMI) and body fat percentage are both used to classify people as normal, overweight and obese.  However, there is a clear difference in the way these two terms are used to analyze a person’s body weight and composition and therefore should not be used interchangeably. 

BMI is just a ratio of a person’s mass (in kilograms) to their height (in meters2) or kg/m2 and as a result doesn’t give any information about a person’s body composition.  This measurement should only really be used for the general population and more specifically those who are sedentary because it doesn’t incorporate any information about a person’s actual body composition, specifically muscle mass.  According to this measurement bodybuilders and athletes, who typically have very low levels of body fat, are classified as overweight or in some instances obese.  This happens because they generally have large amounts of muscle mass and because BMI is just a ratio of weight to height, a larger muscle mass will increase their body weight while leaving the height unchanged and as a result the ratio is increased.

On the other hand, a body fat percentage is a more accurate measurement of a person’s actually body composition and should be used to classify a person as overweight or not.  This will give you very specific information about how much body fat and lean mass (fat free mass) a person has.  That’s why body fat percentages should be used as the standard for classifying people as overweight or not.
I do realize that a BMI is a lot easier and quicker to attain because all you need is a person’s height and weight instead of equipment needed to measure body fat percentage but if at all possible try to use the latter!