FITNESS TESTING
If requested, Thrive HFM will perform laboratory tests to evaluate fitness and performance on an a la carte fee schedule. Testing may include blood work, VO2 Max and anaerobic threshold quantification, and body composition.
1.) MAXIMAL OXYGEN CONSUMPTION (VO2MAX)
What is it?
Maximal oxygen consumption (VO2MAX) is the maximum amount of oxygen that can be used by the body during high intensity exercise. Since oxygen is needed to convert food into energy (ATP), the more oxygen you can consume, the more energy/power/speed you can produce. VO2MAX is often likened to an endurance athlete's performance ceiling or the size of his/her engine. Research has shown that VO2MAX is a significant determinant of performance in endurance-based events such as cycling, triathlon, running, and Nordic skiing.
How is it measured?
Most people already have some idea of what a VO2MAX test entails: an incremental ramp protocol that progresses quickly from walking, talking, and smiling, to sprinting, grimacing, and, most importantly, gasping. As exercise intensity increases, oxygen consumption (VO2) is calculated by collecting and analyzing the test subject's inspired and expired air. With each increase in power output or resistance, more muscle mass will be employed and more oxygen consumed. VO2 will thus increase linearly with exercise intensity until the body reaches its maximum ability to consume oxygen. At this point, oxygen consumption will level off (plateau) and the subject is said to have reached VO2MAX. Other indications of VO2MAX are extreme hyperventilation, a maximal respiratory-exchange-ratio (RERMAX) > 1.0, and a maximal heart rate.
In order to be successful, a VO2MAX test must meet the following requirements:
- Employ at least 50% of the test subject's total muscle mass (i.e. cycling, running, or Nordic skiing). Note that VO2MAX values for cyclists are generally 5-10% lower than those of runners or Nordic skiers due to less active muscle mass.
- Be of sufficient duration to maximize cardiovascular responses (6-15 min).
- Be performed by someone who is highly motivated (i.e. ready for pain and suffering!).
VO2MAX is expressed in two forms. The first value is called your absolute VO2MAX (liters O2/minute) and will likely fall between 3.0-6.0 l/min if you're male, and 2.5-4.5 l/min if you're female. The second value is called your relative VO2MAX (milliliters O2/kilogram body weight/minute). In general, absolute VO2MAX favors large endurance athletes, while relative VO2MAX tends to be higher in smaller endurance athletes.
How do you measure up?
Absolute and relative VO2MAX values of untrained, moderately trained, and elite aerobic individuals.
| |
FEMALES |
MALES |
| Training Status |
Untrained |
Trained |
Elite |
Untrained |
Trained |
Elite |
| Absolute (l/min) |
< 3.0 |
3.0-3.5 |
>3.5 |
<3.0 |
3.5-4.5 |
>4.5 |
| Relative (ml/kg/min) |
26-42 |
40-60 |
55-70 |
36-52 |
50-70 |
60-85 |
Costill, D.L. and Wilmore, J.H. (1994). Cardiorespiratory Function and Performance. Physiology of Sport and Exercise. Champaign, IL: Human Kinetics.
Factors affecting VO2MAX:
- Altitude: An increase in altitude results in a decrease in air density and the partial pressure (or amount) of oxygen in the air. Therefore, you can expect a 5-7% loss in VO2MAX from sea level to Boulder, CO (~5000 ft elevation).
- Age: Peak physiological function occurs at about 30 years of age. VO2MAX decreases approximately 30% between the ages of 20 and 65, with the greatest decline after age 40. However, decreases in VO2MAX can be extremely variable.
- Gender: In general, females tend to have lower VO2MAX values than males - 15% to 20% less. This is primarily due to differences in body composition (college-age females average about 25% body fat while college-age males average 15% body fat), hemoglobin content in the blood (up to 10% lower in females), and heart size (female hearts exhibit less enlargement in response to endurance and resistance training than do male hearts). It is important to note that these differences are "in general" - there are always exceptions.
What does it all mean?
Well, it depends on who you are and what your training status is. Research has determined that approximately 80% of an individual's VO2MAX is genetically determined. Depending on your training status VO2MAX may be enhanced through progressive endurance training. Untrained individuals have the potential to increase their VO2MAX by 15-20% (depending on their initial fitness level), but well-trained athletes are unlikely to realize an increase in VO2MAX of greater than 3-5%.
Since many elite athletes share comparable VO2MAX values, a better measure of fitness and/or predictor of endurance performance is lactate threshold (LT). A high LT allows greater energy production for longer periods of time. And unlike VO2MAX, LT is very trainable.
2.) LACTATE THRESHOLD (LT)
What is it?
Lactate is a by-product of anaerobic metabolism that, despite common misconception, is produced across all exercise intensities. During light and moderate-intensity exercise, lactate is easily absorbed and resynthesized by the muscle cells (production < resynthesis). However, as exercise intensity increases, there comes a point at which lactate removal and/or resynthesis fails to keep up with the rate of lactate production (production > resynthesis). This "point" is referred to as the lactate threshold (LT) and spells the beginning of the end of high intensity exercise. Excessive blood lactate and hydrogen ion concentrations combine to interfere with proper muscle contraction, and you must either slow down or fall over to make the pain stop.
Lactate Threshold thus represents the highest steady-state exercising intensity an athlete can maintain for prolonged periods of time (>15 minutes). Most coaches and sport scientists today recognize LT, or a derivative thereof, as one of the strongest predictors of endurance performance. It also serves as a very useful measure for the determination of training zones and the overall effectiveness of training programs.
How is it measured?
LT tests are typically performed on a treadmill or bicycle ergometer. After an adequate warm-up period, the test starts at an exercise intensity corresponding to 50-60% of the test subject's VO2MAX. Each stage is designed to last 3-5 minutes, allowing sufficient time for the subject to achieve steady-state heart rate, VO2, and lactate production. Blood samples are taken towards the end of each stage to determine blood lactate concentration (a simple finger prick does the trick). The workload is then increased and the process is repeated until an obvious spike in lactate concentration is observed. Heart rate, power output or speed, and VO2 are recorded at each stage.
Blood lactate concentration is measured in millimoles of lactate per liter of blood (mmol/L). LT is typically expressed as a percentage of one's VO2MAX or maximal heart rate. Given two athletes with similar VO2MAX values, it goes without saying that the athlete with a higher LT will go faster longer. LT can also be expressed in terms of cycling power output (i.e. 200 Watts) or running speed (i.e. 9.5 mph).
Where do you stand?
It's all relative. Untrained individuals usually reach LT at about 60% of their VO2MAX and moderately trained folks reach LT at 65-80% VO2MAX. Elite endurance athletes have a very high LT relative to their VO2MAX (85-95% VO2MAX), meaning that they can go very fast for a very long time. Whereas VO2MAX is primarily genetically determined, an athlete who trains properly can significantly increase his or her LT.
Factors that affect the rate of lactate accumulation:
- Exercise intensity: The harder you work, the more lactate your active muscles produce.
- Training status: Proper training develops four primary mechanisms to slow the rate of lactate accumulation:
1.) higher mitochondrial density allows for greater lactate resynthesis
2.) superior fatty acid oxidation prevents lactate production at submaximal exercise intensities
3.) greater capillary density improves both oxygen delivery to and lactate removal from the active muscles
- Muscle fiber type composition: Slow twitch (Type I) muscle fibers produce less lactate at a given workload than fast twitch (Type II) muscle fibers. Proper training can influence the proportion of slow vs. fast twitch muscle fibers.
- Distribution of workload: A large muscle mass working at a moderate intensity will produce less excess lactate that a small muscle mass working at a high intensity. Certain cycling techniques will slow the overall accumulation of lactate by using different muscles.
What does it all mean?
LT is one of the strongest predictors of endurance performance. Increase your LT and you will increase your sustainable power output - i.e., you'll be able to go faster longer (and feel less pain)! Unlike VO2MAX, LT is very trainable.
Pricing For Performance Testing:
| TEST |
COST |
| VO2 Max |
$80.00 |
| LT |
$130.00 |
| LT/VO2 Max |
$200.00 |
| DEXA |
$80.00 |
| DEXA/LT/VO2 Max |
$250.00 |
* All our testing is completed by the Applied Exercise Science Laboratory at the University of Colorado at Boulder.
* Thrive HFM will be happy to evaluate any previous or outside lab testing results.
3.) DEXA scan for body composition and bone density
DEXA stands for Dual Energy X-ray Absorptiometry, and is a state of the
art test that determine an individual's bone density and body composition.
Many methods measure body fat-skinfold measurement with calipers
(anthropometry), bioelectrical impedance, and hydrodensitometry-but
none offer the precision, repeatability and reliability of a DEXA scan.
In addition, DEXA scanning gives a measurement of fat distribution and
bone density. Osteoporosis affects BOTH women and men. With the DEXA
scanner we can calculate the risk of future bone fracture and
determine bone density or strength. DEXA scanning is the "gold
standard" for both bone density measurements and body fat composition.
Although it is a type of x-ray, it is extremely safe. The dose of
radiation is very low and is equivalent to the radiation a person is
exposed to on a flight from New York to Los Angeles.
4.) BLOOD WORK
Thrive HFM can perform a wide range of blood tests for both our Health and Fitness clients. This data is utilizied to optimize both clients performance and well-being. A complete blood screen panel is included in our Optimal Health Program.
* Blood work can be performed on an individual basis with all of our Health and Fitness programs.
