Boulder Performance Lab

Tests

The following information will be provided based on aquired lab data

(please scroll down for details regarding the individual test procedures)

- Lactate Steady State Threshold (LT). Also called the Aerobic/Anaerobic Threshold.

- Power output in watts at LT (on bike) or speed/incline at LT (running)

- Power output in watts at VO2 max (on bike) or speed/incline at VO2 max (running)

- Heartrate at LT

- Training zones, based on LT heartrate

- VO2 max

- Full range (speed or watts) lactate data, heartrate data, and VO2 data

- Respiratory exchange ratio over full load range

- Calories expended (calories/hour) at each wattage or speed interval

- Calories per hour at race pace

- Fat/Carb burn over load range

- Power/pace at ventilatroy threshold

- Maximum HR (VO2 max)

- EKG printout at LT HR (EKG performed upon request, see additional info)

- Blood Glucose levels during graded step test

- Hematocrit test for blood RBC percent

- Pictures of bike form (full extension, 90deg, full flexion) or pictures of gait. Video of bike cadence and running gait provided.

PLEASE NOTE:

BPL frequently customizes specific tests and protocols to an athlete's individual needs.

The Lactate, VO2, RER, and Glucose tests can be peformed STEADY STATE, in addition to linear graded.

Feel free to call to discuss your testing needs in advance of the test session to determine the proper tests and create protocols to provide the most benefit.

TEST DESCRIPTIONS

Lactate Threshold Test

The Lactate Threshold is used to determine an athlete's quantitative performance at their theoretical (or close to it) race pace. Depending on the fitness level of the athlete, the Lactate Threshold effort level is approximately equivalent to a 45 minute to 90 minute race exertion. A highly trained athlete (top pro level) might be able to hold LT efforts for 90 minutes or more. A novice athlete might only be able to hold LT for a maximum of 45 minutes. Typical recreational-level athletes can hold LT for about an hour.

The athlete warms up on the treadmill or bike for 10 minutes at light load or speed. The load or speed is linearly increase at three minute intervals. A blood lactate reading is taken, heartrate recorded and Rating of Perceived Exertion (RPE) is documented at the completion of each three minute interval. This process is repeated until the Lactate Threshold is reached. An additional three data points beyond LT are recorded to ensure an accurate graph.

The start point, and wattage/ speed steps are variable based on the athlete's individual fitness level (bike wattages are from 10-20 watt steps, treadmill speeds are from .3-.5 mph steps). The lactate data is automatically downloaded to the Lactate Scout software. The software then fits a 3rd degree polynomial curve to the data points to determine the Lactate Threshold point.

A side note on LT and what it means to a racer- Depending on the fitness level of the athlete, the Lactate Threshold effort level is approximately equivalent to a 45 minute to 90 minute race pace exertion. A highly trained athlete (top pro level) might be able to hold LT efforts for 90 minutes or more. A novice athlete might only be able to hold LT for a maximum of 45 minutes. Typical recreational-level athletes can hold LT for about an hour.

Additional lactate threshold resources-

http://www.velonews.com/train/articles/8217.0.html

http://home.hia.no/~stephens/lacthres.htm

http://en.wikipedia.org/wiki/Anaerobic_exercise

http://www.unm.edu/~lkravitz/Article folder/lactatethreshold.html

VO2 Max Test

The VO2 max test indicates an athletes maximum utilization of oxygen. A hospital-grade pulmonary analyzer is used to measure the O2 and CO2 an athlete consumes and exhales. The analyzer uses a pneumotach mouthpiece (please see pics page).

The load levels for this test start relatively high, at 85% Lactate Threshold values of wattage (for bike), and 85% LT values of speed (run test). The wattage or treadmill incline is then increased at one minute intervals. The test is continued, with increasing effort, until the athlete cannot physically continue the effort (the athlete makes the call on when to stop the test). The maximal VO2 reached (with heartrate) is the VO2 max point.

Typically, this is a very short duration, yet very strenuous test. Most athletes make it through 5-8 steps (5-8 minutes) before stopping.

Full Range VO2 Max Test

This test is similar to the traditional VO2max test, but the test is performed over the entire wattage or speed range, instead of ust the higher load range. The athlete can then analyze their VO2 levels over the entire load range for baseline data and performance improvement trending.

Additional VO2 max resources-

http://velonews.com/train/articles/8167.0.html

http://home.hia.no/~stephens/vo2max.htm

http://www.coolrunning.com/major/97/training/hampson.html

http://en.wikipedia.org/wiki/VO2_max

Personal PowerTap Usage During Tests

If you use a PowerTap, SRM, or similar real-time power meter for training, the test can be performed based on YOUR power meter readings. BPL has the capability to calibrate the ergometer to match the wattage readout from your power meter.

For example, the constant load interval will still be set at 160 watts, 180 watts, 200 watts, etc, but from your own meter. This ensures that your physiological test results are correlating directly with your actual PowerTap that you use during training and racing.

Respiratory Exchange Ratio

The respiratory exchange ratio (RER) is the ratio of CO2 exhaled, to O2 consumption. The great feature of being able to perform the RER test is the ability to determine the type of fuel (substrate) being used at various load levels, ie, fat or carbs. Chemically and metabolically speaking, pure fat burn produces a 0.7 RER. Pure carb burn produces a 1.0 RER. Typically, the RER readings are lower at a lower load, indicating that more fat is being burned, and as the load increases, the RER number increases as more carbs are utilized by the body. The RER can go as high as 1.2 during the VO2 max portion of the test, indicating heavy anaerobic fueling. The full range VO2 test indicates RER levels across the work load.

Full Range Calorimeter

The full range calorimeter indicates the approximate caloric expenditure rate at load levels. It is very useful to know how many calories your body burns per hour at different training zones, race pace, and max effort. For instance, this data will estimate the calories burned during an hour cycling race, by comparing the LT wattage at that caloric rate.

The calorie burn numbers are computed by using the O2 consumption and the specific RER at a given load or speed. For an RER of 0.7, 4.67 Calories per Liter O2 are burned; compared to an RER of 1.0, which burns 5.05 Calories per liter of O2. The ratio is linear.

For example, if an athlete consumes 3.587 liters of O2 per minute at lactate threshold, and their RER is .95 at that speed, then the approximate calories burned during the race is-

3.587 X 60 miutes X 4.99 = 1073 calories per hour

The caloric burn can be calculated at all load levels.

Blood Glucose Measurements

Typically, during exercise, most athlete's blood glucose levels will fall in the typical range 90-120. If you would like to confirm that your blood glucose levels fall within the normal range, a Blood Glucose test can be performed. The blood glucose measurements can be taken at the same time the blood lactate measurements are taken; from the same blood droplet.

This test is more valuable for athletes that are going to do the steady state or extended graded RER test. Since load or speed is held constant, the variance in blood glucose levels can be analyzed.

Formulas-

VO₂ – CALORIC BURN – RESPIRATORY EXCHANGE RATIO (RER)

VO2 “NUMBER” is normalized by weight- ml/min O₂/ kg

VO₂ raw value is actual Oxygen consumption- ml min O₂

Caloric Burn Rate per hour is oxygen consumption x 0.3

( ml/min O₂ x 60 min/hour / 1000 ml/liter x 5 cal/liter O₂)

5 cal/liter is close approximation at LT. Actually 5.05 for carbs, 4.67 for fat. Look at RER for exact calculation.

RER- ratio of exhaled CO₂ to consumed O₂- VCO₂/VO₂

Pure Fat Burn metabolic chemical equation- RER = 0.7

Pure Carb Burn metabolic chemical equation- RER = 1.0

Anaerobic Burn- RER > 1.0

When the RER falls between 0.7 and 1.0, the percent fat/carb burn is a linear correlation.

Approximate guidelines-

RER 0.70 = 100% fat, 0% carbs

RER 0.75 = 83% fat, 17% carbs

RER 0.80 = 66% fat, 33% carbs

RER 0.85 = 50% fat, 50% carbs

RER 0.90 = 33% fat, 66% carbs

RER 0.95 = 17% fat, 83% carbs

RER 1.00 = 0% fat, 100% carbs

RER > 1.00 = carbs + anaerobic