The Metabolic Efficiency Profile will test your energy and hydration requirements during sustained exercise

Here is a sample Metabolic Efficiency Profile report at the Fit Stop Human Performance Lab 

Energy Utilization Chart

Your report (date, 2013)

During your sub-maximal 30 minute bike test we determined that your ideal power output to spare carbohydrates with optimized fat burn is between 140-180 watts (HR between 108-130 bpm).  At wattages above 200 the utilization of fat is very minimal. Although fat utilization is apparent at 180 watt ranges… the high overall expenditure rate may lead to early depletion of stored carbohydrates (CHO) during continuous long bouts of exercise.

To evaluate energy needs and potential depletion problems I have provided various time at zones scenarios in the following charts – as determined from your Metabolic Efficiency Profile (MEP).

Energy Utilization Scenarios

Full 6 hours/day

The table below represents your energy response if you were pushing near the power output of 180 watts (zone 3) for six hours. Note: negative 336 carbs after ride = potential depletion problems

The next chart represents if you were pushing near the power output of 140 -150 watts (zone 2 heart rate) Note the 758 kcals CHO remaining.  It is easier here to keep your carbohydrate stores in the optimal levels.

The table below represents a range of zones from the 140 to 180 power output (108-130 HR). Here we have 208 kcals of CHO remaining.

30 on / 30 minutes off (during RAAM relay)

NOTE: this determination is based on you ingesting 120 kcals during your ride.  You may choose to focus on hydration during the ride (and after) while focusing on fueling during rest periods. 

Also note:  these determinations do not factor in your fuel intake during rest periods – which will pay a large role in replenishing glycogen.  However, these scenarios – when played out over multiple days, show how it may be difficult to keep up with fuel replacement when intensity is too high.  So be sure to stay in the sustainable zones 1-2 if possible.

Notes on your energy intake requirements

The calculated estimate for your suggested energy replacement during exercise lasting more than an hour is listed to the far right of the grams of carbohydrates every 20 minutes (see below). A more general recommendation is to consume approximately 30-60 grams (i.e., 120-240 calories) of carbohydrates every hour.  Sixty grams is usually the highest amount most endurance enthusiasts can assimilate in an hour or about 30-50% of your actual expenditure. However, some endurance athletes have acquired the ability to consume over 100 grams or 400 calories every hour without bloating or suffering other signs of digestion diversions in blood flow to the stomach. 

Within 1 hour after exercise consuming protein in combination with carbohydrates in approximately a 1:4 ratio (1 gm of protein for every 4 gms of carbohydrate) has shown to speed up the glycogen restoration and muscle recovery. Try to consume between 100-200 grams of carbohydrate within 1-2 hours after exercise (more specifically 1.5-1.6 gm or carb per kg of body weight).

Below are your exercise fuel intake recommendations according to your body weight:

Notes on your hydration requirements

Don't wait until you are thirsty to start drinking. By the time you experience the sensation of thirst you could have already lost up to 2-3% of your body weight from water. Only a 2% reduction can cause significant performance losses and over 3% can lead to heat exhaustion and even heat stroke.

During exercise, studies show that different individuals lose more water faster than others in similar environments (hot, cold, humid, etc.). It is quite individual. So the recommendation for fluid intake during exercise should be determined according to how much water weight you typically lose during your exercise.  If you lose 2 pounds of weight during a 1-hour exercise bout then you should be trying to replace a similar amount during your exercise activities. For each pound of body weight you lose you will want to try to replace it with 16 ounces of water. See your Sweat rate report below:

The information in the above chart represents your sweat rate and the resultant hydration and electrolyte requirements when riding at moderate temperature.  This was a 5 hour local ride.

NOTE: Your sweat rate per hour was 24.8 ounces per hour or 12.4 ounces per half hour which would be your fluid intake goal for each half hour ride.  The electrolyte requirements are listed on the per hour rate.  Cut those in half for the 30 minute ride.

Use your body weight as your metric to determine if you are reaching your hydration needs.

Other Hydration Recommendations to consider

2-3 hours prior to exercise, drink approximately 16-20 ounces of water.

·       10-20 minutes before exercise, drink approximately 10 ounces of water or sports drink.

·         During extreme conditions your hydration requirement per hour can be as high as 34 ounces.

       To determine your individual sweat rate and hydration needs in various conditions – go to http://www.fitstop-lab.com/tools/sweatratesheet.xls  

      Subtract 1 lb for every 16 oz of water consumed during time trial. Once you have confirmed total weight loss, you can then correlate each pound lost with the following loss in electrolytes:

•       220mg of Sodium
•       63mg of Potassium
•       8mg of Magnesium
•       16mg of Calcium

Electrolytes  Recommended electrolyte supplements

      o   http://www.saltstick.com/

      o   http://nuun.com/products

To evaluate your energy expenditure and fuel requirements during extensive exercise training go to http://www.fitstop-lab.com/Metaboliceff.htm or http://www.fitstop-lab.com/fitnesstesting.htm for more testing ideas at the Fit Stop Human Performance Lab

Finish Stronger by maximizing your Economy

Your "economy" or mechanical efficiency (ME) links your sustainable power to your actual performance work rate, velocity or speed.  The better the ME the greater the achieved velocity.  

Your ME is determined by measuring the volume of oxygen taken up by your working muscles at a given sub-threshold exercise intensity. For example, during a bike test your VO2 consumption at a standard power output can be used for comparison. A reduced volume of oxygen at the same power output after repeated testing would suggest an improved oxygen economy and improved performance potential.

At the Fit Stop Lab we measure ME during the Cardio-Metabolic Exercise Profile (CMP) by comparing your actual VO2 ml/kg/min measured at your anaerobic and aerobic thresholds with the predicted VO2 through calculations using the power output. 

We also measure Efficiency and Economy during a 20-minute sub-max exercise test called the Exercise Economy Profile. This test is conducted a couple of days after the CMP and requires performing a 20 minute continuous bike or treadmill test at 80% of your VO2Max.  

Outcomes from the EE Profile include:

GE = The Gross (Mechanical) Efficiency is the ratio of work accomplished to energy expended which describes whole body efficiency. Normal fit cyclists are typically around 20% while Pro Riders average closer to 25%.

EE = Cycling Economy or Running Economy refers to the actual power output generated at a cost of 1 L of oxygen (L= Liter). Highly trained amateurs cyclists generate approximately 75 W/L/min where as the pros are measured in the 85 W/L/min range.

VO2 drift = is commonly referred to as the VO2 slow component. Endurance performance can be enhanced by training to decrease the magnitude of the slow component. World class cyclists show increases of VO2 less than 130 ml over 20 minutes at a work rate of 80% of VO2 max. Unfit or normal fit cyclists will show 3-4 times this amount of drift for 20 minutes at the same relative intensity.  This assessment is a good indicator of how well your aerobic base has been established (or not). Specifically, when you have established a solid aerobic base you will see that during a sub-threshold (below AT) intensity (often best measure is near or at the AeT) the VO2 or heart will maintain a steady straight line consistent with the workrate (i.e., pace or power at AeT).  This is often referred to as "coupling." For more information on coupling check out Joe Friel's article. 

Here is an example of a 20 minute economy test

For more information on fitness testing at the Fit Stop Human Performance Lab go to http://www.fitstop-lab.com/fitnesstesting.htm.

APPLICATIONS

1. For endurance athletes and enthusiasts the benefit of understanding and evaluating your economy is that you can learn to maximize velocities at lower energy expenditure levels by focusing on the appropriate energy systems in training (e.g., zone training).  The right training effect can lead to a faster pace and better conservation of fuel at that pace, while limiting recovery problems.

2. For those individuals who are focused on weight management or more general health and fitness goals the benefit of understanding your economy is two-fold. One, by repeating over and over again the same activities or exercises can lead to mechanical efficiency's that will limit your calorie burn potential.  For example, walking the same flat route over and over again will promote a very efficient walking economy which will lead to faster pace but potentially lower calorie burn.  There is a need then to mix up your routine and the types of exercise.  Two, on the other hand if you plan to go on extensive hikes or other long endurance activities you would like to optimize your economy for that event so that you can finish strong, no matter the distance.

Metabolic Efficiency

Metabolic efficiency can generally be defined as your ability to sustain more work (power, pace, etc.) while using less energy. More specifically ME can be defined as your body's ability to utilize more fat as fuel while sparing your limited amount carbohydrates.

To become more “metabolically efficient” will help you to access more of the 80,000 plus calories you have stored as fat and preserve the less than 2,000 calories available as stored carbohydrates.

Key Points: Training

Key point 1: Low to moderate intensity workouts are a key training component to improving your metabolic efficiency

Long duration and/or more frequent steady state workouts that are at or near the intensity of your Maxfat burn zone, which is about 55-65% of your MaxVO2, will help to optimize your ability to use fat as a fuel and help spare your limited but precious glycogen (i.e., stored carbohydrates).

Estimates are that even while exercising at your max fat burn zone your carbohydrate stores can sustain your effort for only around 5.5 hours before it will become necessary for you to slow down due to depletion problems. Additionally, pushing at intensities that are above that zone can severely shorten that duration potential. Obviously, this information is critically important for long course endurance athletes like Ironman and other ultra-distance athletes, but this concept may also be relevant in helping all athletes and exercisers to burn more fat while training. And this may be critical to recovery and in maximizing your power to weight ratio.

(Note: elite endurance athletes can often burn up to 8 calories per minute at their FatMax while most everyone else will burn less than half that amount).

The renewed focus on the importance of increasing fat utilization (i.e., metabolic efficiency) has been promoted by recent presentations by Registered Dietitian and Exercise Physiologist Bob Seebohar who believes you can “teach your body to burn more fat” and at the same time avoid gastrointestinal (GI) problems that are common with endurance athletes. He has observed that many athletes are not only limiting their potential to use more fat as energy but can actually be lowering their fat use because they are training too hard and consuming too many carbohydrates. This is especially relevant during the lower volume transition and base periods in training programs.

Read Bob Seebohar
http://www.usatriathlon.org/resources/multisport-zone/fuel-station/metabolic-efficiency-training
Sample metabolic efficiency training journey
http://www.usatriathlon.org/resources/multisport-zone/fuel-station/my-metabolic-efficiency-journey

Key Point 2: Increased training volume is the Key to maximizing fat utilization, increasing performance and burning body fat

Another key factor in optimizing endurance performance is your ability to maximize your volume of training by ramping up the frequency, duration and intensity of your training at a rate that you can continue to cope and recover. As long as you are able to adapt to performing more frequent, longer, and more intense workouts you will continue to increase your ability to maximize fat utilization, push up your sustainable pace, and give you an even greater net calorie expenditure. Of course the critical consideration when ramping up your volume is RECOVERY. Generally it takes many phases and even years to lift your training volume up to your potential safely.

Read: Matt Fitzgerald’s Racing Weight
http://www.velopress.com/sample/sample_RW.pdf
How does nutrition fit in the metabolic efficiency equation?

Key Point 3: Nutrition

Seebahor also recommends a periodized approach to eating which includes limiting your carbohydrates especially during your transition and base training periods. During these periods the focus should be on eating fruits, vegetables, lean protein and healthy fats and limiting sugars and grains. Your food intake should adjust according to the volume of your training with carbohydrates only increasing in concentration as training intensity and volume increases.

Read: Paleo Diet for Athletes by Joe Friel and Dr. Loren Cordain
http://www.thepaleodiet.com/paleo_books/forathletes.shtml or Bob Seebahor’s Nutrition Periodization for Athletes
http://www.amazon.com/Nutrition-Periodization-Endurance-Athletes-Traditional/dp/0923521836

In summary:Maximizing your endurance training effects will require walking a delicate line between pushing too hard too frequently which can limit your ability to use fat as a fuel, leading to early plateaus in your endurance fitness. On the other hand the volume in your training will need to be progressed with an appropriate dose of intensity to continue to maximize both fat utilization and sustainable power. Nutrition can play a critical role in helping you adapt to the training cycles necessary to reach your peak fitness. A periodized approach both to your training volume and your fuel intake is critical to your success.

Strategies:• During your base training periods start eating mostly fruits, vegetables, lean protein and healthy fats. Consider a periodized nutrition plan.
• Start Tracking all your exercise and food intake on http://www.trainingpeaks.com/
• Consider tracking your power to weight ratio and metabolic efficiency at a credible human performance testing lab.
o Test your metabolic efficiency on the treadmill, bike or both to evaluate your current ability to burn fat and to determine your max fat burn zone.
o Re-test your metabolic efficiency if the baseline test determined that your fat utilization was limited.
o Test your body composition to evaluate body fat% and lean mass changes.
o The goal with this testing is to set your training parameters (i.e., what pace and heart rate is associated with my max fat level) and to determine if your training and nutrition changes are having the desired effect.
Seebohar refers to the crossover point as the"Metabolic Efficiency Point" which is the intensity where carbohydrates first begin to burn at a greater rate than your fat energy. The goal is to move this point to the right on the graph below so that the Metabolic Efficiency Point will occur at higher pace or power outputs. To determine your individual crossover you’ll need to get tested.

If you have an interest in optimizing your metabolic efficiency the Fit Stop is currently offering an opportunity for you to experiment with some of these concepts by participating in our Metabolic Exercise Profile. This testing will provide the following useful information and tools to help you maximize your endurance potential and a greater ability to decrease your body fat:

• An Exercise Metabolic Assessment to determine your current Maxfat level, aerobic threshold, and cross-over point (where you begin to burn more carbohydrates than fat).
• Determine your metabolic training zones for heart rate, power and pace.
• Receive your own energy expenditure table which will list your calories expenditure rate for carbs and fat at various sub-maximal intensity levels. See sample table at www.fitstop-lab.com/tools/metabolicefficiency.xls
• An exercise physiologist will also help you set-up your training program and tracking system using the Training Peaks platform.
• Re-evaluations will be included at half price.

Contact us at kjnico@fitstop-lab.com or call 760-634-5169