Sunday, June 16, 2013

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