VIII.3.3. Lab tests or lab tests substituted with motor tests
The primary aim of different performance diagnostic examinations is to specify athletes’ functional capabilities. The more functions are specified the more precise picture is available to get information about their training status. Several ergo-metric protocols test functional capabilities. The method that we opt for mainly depends on which process of metabolism is intended to examine. We can collect data from aerobe energy/ power supply through the measurement of gas exchange. By specifying the parameters of lactic acid concentration and acid-base balance we can gain information about anaerobe energy/ power supply.
- The determination of aerobic capacity and maximal oxygen intake
In aerobe conditions human body is capable to work more economically therefore the development of aerobic capacity is the primary aim of fitness programs. Athletes’ aerobe fitness tests measure their maximal oxygen intake. In Gyögy Gyetvai’s view the aerobic capacity is “the total amount of energy from the anaerobe energy systems. Maximal oxygen consumption (mil/min) reflects the aerobe physical fitness of the individual”. In practice mainly the relative aerobic capacity is defined and it is expressed with oxygen unit weight relation. Endurance and stamina are considered good if it is above 60ml/kg/min. The aerobic capacity is measured when most of the muscles of a body are moving and it leads to depletion and fatigue within 6-12 minutes. The value of the progressively increasing loading is measured in every 1-3 minutes. One of the most relevant methods of determining aerobic capacity/ power is the measurement of maximal oxygen uptake (VO2max) under laboratory conditions. It is a simple and safe technique and it requires an all-out effort, usually on a treadmill or bicycle, performed under a strict protocol in a sports performance lab. These protocols involve specific increases in the speed and intensity of the exercise and measurement of the volume and oxygen concentration of inhaled and exhaled air. This determines how much oxygen the athlete is using. An athlete’s oxygen consumption rises in linear relationship with exercise intensity up to a certain point at which oxygen consumption plateaus. This marks VO2max.
There has been lots of effort invested in finding another method of estimating VO2max that is, applying simple motor capability tests. Several international studies have proved that spiroergometric tests carried out in labs the oxygen consumption correlates to some well known endurance tests. In this examination athletes are subjected to physical stress either in a 12 min long running test or a 20 meter pacer test and it has been stated that these are appropriate methods to assess aerobic capacity. It is also true that the results of these tests are affected by the conditions within which the measurements are registered. The formula of Dr. Kenneth H. Cooper’s 12 minute running test supports us calculating and estimating the maximal oxygen consumption: Vo2max ═ (t-505)/45, “t” indicates the covered distance in meters during the 12 minute running test.
The researchers of the Danish Aarhus University have produced a formula based on resting heart rate, which calculates oxygen consumption: VO2max ═ (HRmax/HRrest)x 15, HRmax indicates maximal heart rate whereas HRrest shows the values of resting heart rate.
- Estimating anaerobic capacity and lactic acid concentration
From our feed stuff and nutrition we can gain energy not only under aerobe but also anaerobe condition. Our body needs anaerobic energy if oxygen intake exceeds the anaerobe threshold. The anaerobe capacity can be calculated from the quantity of lactic acid. The value of lactic acid can be estimated from athletes’ blood samples (1-2 drops taken from the earlobe). From the blood sample taken during and at the end of loading (within 3-4 minutes) blood pH shows if loading has reached its peak. On the basis of these values professionals can access athletes’ physical condition and fitness. Due to anaerobic exercises pH decrease is produced under higher performance and achievement and athletes can endure excessive decrease of pH. Anaerobic capacity characterizes the quantity of energy source which does not demand oxygen consumption. Energy can be gained anaerobically during very intensive exercises, for example, sprint running. The measured values show athletes’ explosive strength and power. The outcomes of these assessments may help opting for sports or posts in a team.
Estimating anaerobic capacity has been in the focus of professionals for a long time. Its rate can be estimated from the quantity of lactic acid, which is a by-product, although oxygen is not used. These processes should be carried out under lab conditions even in case of a more expensive test, such as Wingate test on a cycle ergo-meter measuring peak anaerobic power and capacity.
Vertical jump or vertical leap test (see illustration 7) is a useful method to assess and determine basic athletic capabilities especially in sports where jumping is compulsory. It is also a widely used test for estimating anaerobic capacity. It is the act of raising athletes’ centre of gravity higher in the vertical plane solely with the use of muscles.
This method assesses and estimates athletes’ aerobic capacity with high precision.
Athletes should reach up against a flat wall and mark off the highest point they can reach flat-footed. They take jumps from a standstill and with a 90 degree angle of knee flexion and maximal force jump up vertically. The height of jumps is measured. Besides this athletes’ weight is also measured.
The formula of Sayers and et al (Med. Sci. Sports. Exerc. 31:572-1999) assesses average power based on falling body equation.
(Maximal Anaerobic Power (w) ═ (60.7 x vertical jump cm) + (45,3 x body weight kg) – 2055.
It is useful to convert the score to units of power or work. It would be also worth looking at the percentile norms for peak power in the publication of Maud and at al (Res. Q. Exerc. Sport, 60: 144 – 1989)