PEAK 404 EXERCISE PHYSIOLOGY LAB 2. Cardiovascular Function

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1 PEAK 404 Lab 2 Page 1 of 6 PEAK 404 EXERCISE PHYSIOLOGY LAB 2 Cardiovascular Function Introduction Incremental exercise is often used to determine maximum aerobic capacity (V. O 2 max). It provides a gradual increase in intensity that the body responds to with a change in heart rate, blood pressure, oxygen consumption, carbon dioxide production, and ventilation. All of these responses support the increased metabolic demand which reflects the metabolic demand. Certain factors increase linearly with the increase in intensity, which makes them valuable as tools for estimating other factors. Two. of these are heart rate, which becomes linear above 120 bpm and VO 2. By plotting the linear increase in one prior to maximum, the other can be predicted. Practically speaking, maximum capacity can be predicted through sub maximum effort. Mean arterial pressure (MAP) describes the average pressure during a cardiac cycle while a person is at rest. It is important because it determines the rate of blood flow through the systemic circuit. When a greater volume of blood is pumped, it encounters a greater resistance (pressure). Reduced MAP indicates the ease at which blood can circulate. Calculate MAP with the following: MAP = DBP + [.33 x (SBP DBP)] The workload the heart must endure is related to both how fast it must beat and the pressure it encounters when it moves blood through the systemic circuit. When the heart contracts faster, its demand for oxygen increases because its metabolism increases to meet the energy needs. The heart must contract more forcefully as it encounters greater resistance, which further increases the oxygen and energy demand of the heart muscle. The heart that works less (lower HR and SBP) for a given intensity is a heart that functions efficiently. The work the heart performs is described as Double Product and it is calculated with the following: Double Product = HR x SBP.

2 PEAK 404 Lab 2 Page 2 of 6 1. Incremental Treadmill Exercise The purpose of this portion of the lab is to observe HR,V.O 2 and BP responses during rest and sub maximal incremental exercise. Additionally,. this information will be used to predict maximum and sub maximum HR, VO 2 and intensity. Lab Activity 1A. Each group will have one subject perform this activity, while the other group members will be responsible for data collection. Heart rate will be monitored by palpation or via a Polar Heart Rate Monitor. Blood pressure will be determined by auscultation. Once the subject has been appropriately prepared (i.e., heart rate monitor placement, blood pressure cuff placement), the subject will quietly sit for 3.0 min, during which resting measures will be made at the end of each minute. Next the subject will walk on the treadmill for approximately 6.0 min, with increases in work rate occurring at the end of each minute. Exercise begins with a speed of 5.0 mph and increases at 0.5 mph increments through 6.0 minutes. Heart rate, BP, and V. O 2 measurements should be made during the last min of each stage. Recovery measurements should be made for 4 minutes of post exercise walking at 3 mph. Record all data on the data form. Note: The arm in which blood pressure is being taken should be supported during measurements by the technician and not resting on the handlebar. This will reduce the noise heard from the treadmill. Lab Assignment 1A. Each student will be responsible for obtaining a data table from his/her group. You will be provided the opportunity to copy an Excel formatted report of your group s data, which will be necessary for the lab assignment below. You will need an IBM formatted disk for class in order to obtain a copy of the data. 1. Use the treadmill exercise data to plot HR vs. intensity (speed) on a scatter plot using Microsoft Excel. The X-axis should represent running speed; the Y-axis should represent HR. (a) Extrapolate the HR line to age predicted maximum HR. (b) Use the HR data to predict the intensity (speed) that would elicit 60% and 75% of maximum HR. (c) Mark and label those points on. the graph. 2. Use the treadmill exercise data to make a scatter plot. HR vs. VO 2. The X-axis should represent running speed; the Y-axis should represent HR. (a) Extrapolate the HR line to age predicted maximum HR.. (b) Use the HR data to predict maximum, 60%, and 75% of maximum VO 2. (c) Mark and label those points on the graph. 3. Use the BP data to plot a graph of SBP and DBP vs. work rate. Label all graphs appropriately (x-axis and y-axis) and provide a title.

3 PEAK 404 Lab 2 Page 3 of 6 2. Incremental Cycle Ergometry Lab Activity 2A. Each group will have one subject perform this activity, while the other group members will be responsible for data collection. Heart rate will be monitored by palpation or via a Polar Heart Rate Monitor. Blood pressure will be determined by auscultation. Once the subject has been appropriately prepared (i.e., heart rate monitor placement and blood pressure cuff placement), the subject will quietly sit on a Monark Cycle Ergometer for 3.0 min, during which resting measures will be made at the end of each minute. Next the subject will cycle on the ergometer for approximately 6.0 min, with increases in work rate occurring at the end of each minute. Specifically, each subject maintains pedal cadence at 50 rpm. Exercise begins with a resistance of 1.0 kg and increases by 0.5 kg increments every minute through 6.0 min. Heart rate and BP measurements should be made during the end of each 1 min stage. Recovery measurements should then be made during 4 minutes of pedaling at 0.5 kg. Record all data on the data form. Lab Assignment 2A. Each student will be responsible for obtaining a data table from his/her group. You will be provided the opportunity to copy an Excel formatted report of your group s data, which will be necessary for the lab assignment below. You will need an IBM formatted disk for class in order to obtain a copy of the data. 1. Use the cycle ergometry exercise data to plot HR vs. intensity (work rate) on a scatter plot. The X-axis should represent work rate; the Y-axis should represent HR. (a) Extrapolate the HR line to age predicted maximum. (b) Use the HR data to predict maximum work rate, 60% of max, and 75% of max. (c) Mark and label those points on the graph.. 2. Use the cycle ergometry exercise. data to plot HR vs. VO 2 on a line graph. The X-axis should represent VO 2 the Y-axis should represent HR. (a) Extrapolate the HR line. to age predicted maximum. (b) Use the HR data to predict maximum VO 2, 60% of max, and 75% of max. Mark and label those points on the graph. 3. Use the BP data to plot a graph of SBP and DBP vs. work rate. Label all graphs appropriately (x-axis and y-axis) and provide a title. 4. Present your maximum and percentage of maximum data for each subject and from each exercise task in a presentation table. Label it appropriately.

4 PEAK 404 Lab 2 Page 4 of 6 3. Mean Arterial Pressure and Double Product The purpose of this portion of the lab is to determine the rate of blood flow through the systemic circuit at rest through the calculation of MAP. A secondary purpose is to determine the workload the heart endures at rest and during incremental exercise. Lab Activity 3A. Collect resting HR and BP data from your cycle ergometry and treadmill exercise subjects. Calculate MAP for both at rest. Calculate Double Product for both at rest, during the second, fourth, and last minute of incremental exercise. Lab Assignment 3A. 1. (a) Plot the MAP of both subjects on a column graph. (b) Plot the Double Product of both subjects on a column graph. 2. (a) Report your MAP and Double Product data in a presentation table. (b) Describe the differences between subjects and between exercise modes. For example: which activity elicited a greater metabolic demand from the heart? How do the subjects differ in their MAP and in their Double Product? Data Forms RESTING HEART RATE AND BLOOD PRESSURE Subject HR (bts/min) SBP SBP/DBP

5 PEAK 404 Lab 2 Page 5 of 6 Data Forms REST, INCREMENTAL TREADMILL EXERCISE, AND RECOVERY Subject: Stage/Time (min) Speed (mph) SBP DBP HR (bpm) VO 2 (ml/kg/min) Rest Exercise Stage 1 Stage 2 Stage 3 Stage 4 Stage 5 Stage 6 Recovery min 4

6 PEAK 404 Lab 2 Page 6 of 6 REST, INCREMENTAL CYCLE ERGOMETRY, AND RECOVERY Subject: Stage/Time (min) Work Rate (kgm/min) SBP DBP HR (bpm) VO 2 (ml/kg/min) Rest Exercise Stage 1 Stage 2 Stage 3 Stage 4 Stage 5 Stage 6 Recovery min 4