Exercise testing Laboratory exercise testing W 170 and

Exercise testing Laboratory exercise testing: W 170 and maximal tests

W 170 Exercise test estimating theoretical physical working capacity at hear rate of 170 beets/min. The test is looking for a theoretical load (P) [W] which should be produced by tested person at his (her) HR 170 beets/min. Physiological principle: A linear relation (positive correlation) between HR and intensity of exercise (load) in a range from 120 to 170 (180) beets/min. Note: There is no change in systolic volume from 120– 170 (180) beets/min and therefore cardiac output depends only on heart rate. Systolic volume rises till 120 beets/min, from 170– 180 beets/min slightly decreases (short diastole). *

W 170 Next characteristics: 1) It is one of the oldest sub-maximal tests evaluating fitness level, an effect of a training or impact of a rehabilitation intervention…. 2) There was a hypothesis of strong correlation of the test with an aerobic power (VO 2 max). However, current findings show, that the test is valid only for common population (mainly for men). It is not suitable for athletes. 3) HR 170 beets/min is approximately the value when is a healthy young man reaching his anaerobic threshold. For the elderly or ill (who has reduced HRmax and HR at An. T) is sometimes used modification of the test W 150 či W 130. *

W 170 Equipment: - cycle ergometer - HR monitor Protocol: 1) 2(sometimes 3– 4) stages. There can be 1 min long optional pause between stages. 2) duration of each stage 4– 6 min (reaching of steady state) 3) measurement of HR at the end of each stage (during last 15 s) 4) load [W] should increase HR: - at the end of the 1. stage: 120– 140 bpm - at the end of the 2. stage: 140– 160 bpm *

W 170 Determination of the load [W] per kg of weight: ♂ ♀ and trained children 1. stage 1, 5 W/kg 1 W/kg 2. stage 2 W/kg ≥ 2 W/kg 1, 5 W/kg ≥ 2, 5 W/kg Final power depends on pedal rate as well. The pedal rate should be kept in the range ± 5 revolution/min. Optimal pedal rate for sedentary is 60 rev/min (55– 65), for trained higher (even 85– 95). The higher is load, the higher should be pedal rate. *

W 170 Protocol (♀ 60 kg): 145 bpm [W] 125 bpm 90 W Result of the test: 1) 60 W = 125 bpm 2) 90 W = 145 bpm 3) x W = 170 bpm HR 2 HR 1 60 W 2. stage 1. stage [min] 5 min *

Calculation of W 170 (extrapolation) × × 140 *

Calculation of W 170 (extrapolation) Result of the test: 1) 60 W = 125 bpm 2) 90 W = 145 bpm 3) 140 W = 170 bpm × × Index W 170: 140 W : weight (60) = 2, 33 W/kg 140 *

W 170 Population norms: (Heller, 2005) *

Comparison of a untrained (N) and a trained (T) with use of three stages *

W 170 To create a line, two points are enough. It means to realize W 170, two exercise stages should be enough too. There are some authors who recommend at least three stages. More stages reduce the risk of error. × × × *

W 170 Note: If the HR at the end of the first stage is lower than 120 bpm, there may be a risk of major error. The reason is linearity from 120 to 170…. . In this case it is useful to add the third stage. *

W 170 test can be use for evaluation of working capacity at higher HR as well. However, by reason of above mentioned problems of linear relation… there is at HR higher than 170 -180 bpm increase in error of the evaluation. W 170 test can be use for indirect determination o aerobic power: 1) Realization of standard test and determination of load at HRmax which can be calculated from formula 220 -age 2) Determined load is used in formula (Bunc, 1989): VO 2 max (ml/min) = 10. 88 × [W] + 411 - This formula can be used for load from 100 to 400 W, with considered error 10%. *

Indirect determination of VO 2 max for ♀ 60 kg, 20 year W at HRmax? 1) 220 -20= 200 bpm 2) 190 W = 200 bpm × VO 2 max = 10. 88 × [W] + 411 VO 2 max = 10. 88 × 190 + 411 VO 2 max = 2478 ml/min × 2478 : weight (60 kg) VO 2 max = 41, 3 ml/kg/min 140 190 *

Maximal exercise test Laboratory tests when the load is gradually increasing till maximum. The main aim is to measure maximum oxygen consumption (aerobic power) - VO 2 max(peak). It means to evaluate efficiency of cardiovascular system and estimate working capacity or working tolerance. Sometimes is called spiroergometri. A working capacity is a load reached immediately before appearance of the signals of ischemia on EKG record, which are the reasons to stop the test. A working tolerance is the highest load at the maximum, when the criteria for termination of the test were reached. *

Maximal exercise test The sources of the load: - cycle ergometer - treadmill - arm ergometer Next equipment: - HR monitors - unit for pulmonary gas exchange (PGE) measurement - analyzers for measurement of O 2 a CO 2 in inspired and expired air (importance of calibration one time per day- mixture of gases: e. g. CO 2 – 5 %, O 2 – 15 %, rest N 2) - flow sensor measuring volume of inspired and expired air (importance of calibration before every measurement) Every devises are controlled from one PC = spiroergometrics unit *

Spiroergometrics unit Mixture of calibration gases Calibration pump Suction pump for EKG Suction electrodes EKG PC HR receiver Unit for PGE measurement EKG

Unite for pulmonary gas exchange measurement Measurement of O 2 consumption and CO 2 production - from difference in concentration in inspired and expired air Measurement of ventilation - calculation from breathing frequency and tidal volume Tested person wears mask or mouthpiece with clamp Mouthpiece – discomfort, but lower death space Maska – comfortable (breathing via nose), but bigger death space (accumulation of CO 2) + leaking. *

Air sampling for CO 2 analysis Information about volume of inspired and expired air Mast fit.

Flow sensor working on principle different pressure in the front of and behind of membrane. Disinfection and calibration prior to each measurement.

Maximal exercise test Increase in the load: - continual (ramp) test [W] [W/kg] O 2 There is steples increase in the load [W] till maxima. Problem: delay in O 2 consumption VO 2 does not correspond with the load. [min] *

Maximal exercise test Increase in the load: - gradual (step) test [W] There is gradual increase in load [W] with use of steps from low values to maxima: [W/kg] 0, 5; 1; 2– 5 min. O 2 consumption corresponds to the load at the end of each step (reaching steady state) [min] *

Maximal exercise test Increase in the load: Every minute (step) increase about o 1/3 W/kg of waight. VO 2 should not increase between steps more than 3 METs. - ♂ 75 kg = 25 W/min - ♀ 60 kg = 20 W/min Total duration of the test should be from 8– 12 min. If the test is shorter or longer, VO 2 max values are lower. Generally – for sedentary, obese and elderly, tests should e longer with lower increase in load) *

Maximal exercise test Increase in the load : Sedentary male: Wmax = 175 (around). If increase about 25 W/min, duration will be 7 minutes. Trained cyclist Wmax = 550 (or more). If increase about 25 W/min, duration will be 22 minutes. Solution: higher increase (30 W) + change in exercise protocol: 1) 4– 5 min warming-up at constant low intensity 2) test starts at the load corresponding with load at individual anaerobic threshold *

Maximal exercise test Sedentary: 7 steps x 25 W = 175 W *

Maximal exercise test Trained would need by 22 steps x 25 W = 550 W Problem: 1) Long duration 2) Low (boring) intensity at the beginning ACCORDINGLY 550 W *

Maximal exercise test Trained would need by 22 steps x 25 W = 550 W Problem: 1) Long duration 2) Low (boring) intensity at the beginning ACCORDINGLY 550 W Minute long brake, not necessary W at An. T Test: 3– 8 min 4– 5 min *

Maximal exercise test How to estimate An. T? THAN 1) Based on population norms. . . 2) By using W 70 test, which could serve as a warming-up at the same time 550 W W at An. T test: 3– 8 min 4– 5 min *

Maximal exercise test How to estimate An. T? Using W 170 test as a warming-up before test to maximum 550 W W 170 Test: 3– 8 min 2. step 1. step *

Maximal exercise test Chosen monitored parameters: 1) Heart rate (HRmax, HR at An. T) and saturation Saturation HR Digital pulse oxymetere A saturation means percentage of saturation of blood bye O 2 from maximum possible amount. It is at the rest about 98% and decreases during exercise. It can be lower than 90% at maximum exercise. *

Maximal exercise test Chosen monitored parameters: 1) Heart rate (HRmax, HR at An. T) and saturation 2) Power – P (Wmax, W at An. T) Work = force acting upon a distance = [N × m] = [J] power = work for time = [Nm/s] = [W] Or… force speed P=F×v [W = Nm/s] *

Maximal exercise test Chosen monitored parameters: 1) Heart rate (HRmax, HR at An. T) and saturation 2) Power – P (Wmax, W at An. T) The values of Wmax/kg: ♂ ♀ trained KVS illnesses 3, 5 2, 8 ≥ 6– 9 od 0, 5 See next table: *

Maximal exercise test Chosen monitored parameters: 1) Heart rate (HRmax, HR at An. T) and saturation 2) Power – P (Wmax, W at An. T) 3) Lactate – for estimation of so called metabolic An. T *

Invasive estimation of An. T from level of a blood lactate (Placheta et al, 2001) *

Maximal exercise test Chosen monitored parameters: 1) Heart rate (HRmax, HR at An. T) and saturation 2) Power – P (Wmax, W at An. T) 3) Lactate – for estimation of so called metabolic An. T 4) Gas exchange (O 2 a CO 2) and ventilation RQ = CO 2 RQ of fats = 0, 7. RQ of carbohydrates = 1 However during maximal exercise test RQ overlap level of 1. The reason is reduction of acidity with help of bicarbonates: H++ HCO-3 → H 2 CO 3 → H 2 O + CO 2 Note: H 2 CO 3 - carbonic acid *

Maximal exercise test However during maximal exercise test RQ overlap level of 1. The reason is reduction of acidity with help of bicarbonates: H++ HCO-3 → H 2 CO 3 → H 2 O + CO 2 [l] O 2 Deflection point from linear trend between CO 2 output and exercise intensity. An. P [W] *

Maximal exercise test This deflection point represent anaerobic threshold, which is called as a respiration or ventilation An. T. Similar increase (deflection point) can be seen on the curve of ventilation - because increase of p. CO 2 in blood stimulates ventilation (due to chemoreceptors). V [l] So called „talking“ test can be used for estimation. Ventilation An. T [W] *

Determination of ventilation An. T (Tvent) (Heller, 2005) *

V-slope method for determination of An. T Linear relation is disturbed for the benefit of CO 2 output. *

O 2 consumption during maximal test (Heller, 2005) *

O 2 consumption during maximal test Plateau in O 2 consumption: 1) It is situation when VO 2 max is reached and next increase in exercise intensity does not cause father increase of it. 2) It is possible to sustain for seconds (trained longer). 3) It is evident among less then 50% tested. The most of the tested finish early from reason of uncomfortable filings. 4) It is one criteria for reaching maximum exercise intensity. *

Maximal exercise test is ended when the tested feels inability to continue - reaching volitional maximum Maximum = at lest 18. (Borg, 1982) *

Criteria of reaching maximum 1) Plateau in VO 2. 2) RQ higher than 1. 3) Lactate is 1, 5 min after cessation of exercise >8 mmol/l 4) HRmax >85 % from predicted maximum VO 2 max x VO 2 peak. *

Maximum test on treadmill The example of the set used in our laboratory: 4 min 1 min Tr. ♂ km/hour % 8 0 8 5 Tr. ♀ km/hour % 7 0 7 5 than increase every 30 s 10 11 12 13 14 15 15 5 5 5 7 Than increase in inclination 8 9 10 11 12 12 12 about 2 % 5 5 7 9 11 *

Receiver of HR. Safety belt.

Maximum test on treadmill Example of next protocols: *

Some parameters during maximal test VCO 2 – volume of expired CO 2, RER – respiration quotient, V – ventilation, FIO 2–FEO 2 – utilization of O 2 from ventilated air *

Some parameters during maximal test VE – ventilation VCO 2 – volume of expired CO 2 VO 2 – volume of inspired O 2 PETO 2 – partial pressure of O 2 at the end of expiration PETCO 2 – partial pressure of CO 2 the end of expiration LA – level of lactate HCO 3 - – bicarbonate R – respiration quotient p. H – p. H W – load *

Results of maximal exercise test

Results of maximal exercise test

Results of maximal exercise test

Results of maximal exercise test VO 2 l/min

Measurement of VO 2 in the field conditions A B *

Determination of VO 2 max from regression equation (Jurča el al. ) 1. Evaluation of physical activity *

Determination of VO 2 max from regression eguetion (Jurča el al. ) 2. Filing of different parameters *

Výpočet VO 2 max dle regresní rovnice (Jurča el al. ) 3. Final evaluation of results *

Literature: Heller, J. (2005). Laboratory Manual for. Human and Exercise Physiology. Charales Univeristy in Prague: The Karolinum Press. Maud, C. Foster (Eds. ). Psychological assessment of human fitness. Champaign, IL: Human Kinetics. Placheta, Z. , Siegelová, J. , Štejfa, M. , Jančík, J. , Homolka, P. , & Dobšák, P. (2001). Zátěžové vyšetření a pohybová léčba ve vnitřním lékařství. Brno: Masarykova Univerzita. Silbernagl, S. , & Despopoulos, A. (1988/1993). Atlas fyziologie člověka (E. Trávničková et al. , Trans. ). Praha: Grada. *