Current Physiology Experiments

Physiology Experiments An audit of current physiology experiments used in Universities, Science Centres and Museums Report commissioned by the Wellcome Trust

Prepared by Drs Valerie Gladwell, Kate Reed, & Gavin Sandercock at the University of Essex, in conjunction with The Physiological Society

Contents Acknowledgments......................................................................................................................6 List of abbreviations...................................................................................................................7

SECTION 1: UNDERGRADUATE PHYSIOLOGY EXPERIMENTS ..................................................................8 1.1 Physiology sub-section: BLOOD .....................................................................................................10 Predicting VO2 max using the 20m shuttle run (Bleep Test) (BL 01) .......................................12 Predicting VO2 max using the Forestry Step test (BL 02) .........................................................12 Predicting VO2 max using the Harvard Step test (BL 03)..........................................................12 Coopers 12 min run test, a prediction test (BL 04)..................................................................13 Ratings of perceived exertion and the intensity of exercise (BL 05) .......................................13 Taking blood pressure using a manual cuff and a stethoscope (BL 06)...................................14 Using a stethoscope to identify heart sounds (BL 07) .............................................................14 Taking blood pressure using automatic and manual methods; rest and exercise (BL 08) ......15 Predicting VO2 max using the YMCA protocol for cycling (BL 09)............................................15 Assessing haemoglobin content in blood (BL 10) ....................................................................16 Taking an electro cardiogram at rest and during activity (BL 11) ............................................16 The Diving Reflex (BL 12) .........................................................................................................16 Effects of exercise on ECG (BL 13) ...........................................................................................17 Predicting VO2 max using Astrand-Rhyming Nomogram (BL 14).............................................18 Observing the effects of temperature on CV and respiratory parameters (BL 15) .................18 Determining maximal oxygen uptake using (treadmill) (BL 16) ..............................................19 Determining maximal oxygen uptake (Bruce Protocol) (BL 17)...............................................20 Summary of popular treadmill tests ........................................................................................20 Determining maximal oxygen uptake (cycle) (BL 18) ..............................................................21 Heart rate deflection point (Conconi Test) (BL 19)..................................................................21 The effects of exercise on the human body (BL 20) ................................................................22 Exercise pressor response (BL 21) ...........................................................................................22 Skin blood flow response to reactive hyperaemia and exercise (BL 22) .................................23 Acute effects of exercise on cardiovascular function (BL 23)..................................................23 The effects of endurance and strength exercise on CV response (BL 24) ...............................24 Blood lactate sampling at rest and during exercise (BL 25).....................................................24 2

Determining onset of blood lactate accumulation and lactate threshold (BL 26) ..................25 Analysing the components of blood (BL 27) ............................................................................25 Elastic recoil in arteries and veins (BL 28)................................................................................27 The structure of the heart (BL 29) ...........................................................................................28

1.2 Physiology sub-section: BREATH.....................................................................................................29 Effects of breath holding (BRE 01) ...........................................................................................30 Effects of exercise on carbon dioxide output (BRE 02)............................................................30 Assessment of resting lung volumes (BRE 03) .........................................................................31 Using a spirometer to assess lung function (BRE 04)...............................................................31 Observing the effects of exercise on respiratory rate and minute volumes (BRE 05).............32 Assessment of ventilation change during exercise (BRE 06) ...................................................33 Effects of load carriage on economy of walking (BRE 07) .......................................................33 Assessing muscular efficiency (BRE 08) ...................................................................................33 Ventilation: Normal volumes and observing the effects of acute exercise (BRE 09) ..............34 The structure of the lungs (BRE 10) .........................................................................................34 Determining the ventilatory threshold (BRE 11) .....................................................................35 Oxygen kinetics during exercise (BRE 12) ................................................................................35 Estimating maximal oxygen uptake using gas analysis (BRE 13) .............................................36 Maximal accumulated oxygen deficit (MAOD) (BRE 14) .........................................................37 Simulated altitude during exercise (BRE 15)............................................................................37

1.3 Physiology sub-section BRAIN.........................................................................................................39 The stretch reflex (BRA 01) ......................................................................................................40 The stroop test (BRA 02)..........................................................................................................40 Music and performance (BRA 03) ............................................................................................40 The effective of practice on skill acquisition (BRA 04).............................................................41 The effect of imagery on skill (BRA 05)....................................................................................41 The effect of caffeine on reaction time (BRA 06) ....................................................................42 Reaction time study series 1-5 (BRA 07)..................................................................................43 Reaction time of race start (BRA 08) .......................................................................................45 Ulnar Nerve Conduction (BRA 09) ...........................................................................................45

1.4 Physiology sub-section: BRAWN ....................................................................................................47 3

Isometric handgrip strength test (BRW 01) .............................................................................48 Simple muscle fatigue (BRW 02)..............................................................................................48 Relationship between muscle size and strength (BRW 03) .....................................................48 Estimation of muscle mass and regional muscularity (BRW 04) .............................................49 Force-power relationships in muscle contraction (BRW 05) ...................................................49 Estimation of fat free mass using bioelectrical impedance analysis (BIA) (BRW 06) ..............50 Field tests for power (BRW 07) ................................................................................................50 Anaerobic step test (BRW 08)..................................................................................................51 Sprint tests (BRW 09) ...............................................................................................................51 Strength testing with goniometry: effect of joint position on strength (BRW 10) ..................52 The Borg cycling strength test with constant load (BRW 11) ..................................................53 Power 170 Test (BRW 12) ........................................................................................................ 53 Using a flywheel dynamometer to estimate velocity / power relationships (BRW 13) ..........54 Muscle strength: 1 Repetition max and fatigue (BRW 14) ......................................................55 Optimisation of Human Power output (BRW 15) ....................................................................55 Maximal Anaerobic Running Test (BRW 16) ............................................................................56 The Wingate Test: A measure of power (BRW 17) ..................................................................57 Basic EMG activity (BRW 18).................................................................................................... 57 Muscle fatigue and EMG (BRW 19)..........................................................................................58 Assessment of muscle flexion during isokinetic knee flexion and extension (BRW 20)..........58 Assessment of isometric force-joint position relationship (BRW 21)......................................59 Assessment of electromechanical delay (EMD) of the knee flexors associated with static maximal voluntary muscle actions (BRW 22) ..........................................................................59 Assessment of electromyographic signal amplitude and force of the knee flexors associated with static voluntary muscle action (BRW 23).........................................................................60

1.5 Physiology sub-section: BONE ........................................................................................................61 Measuring joint angles (BO 01)................................................................................................62 Finger length and sport ability (BO 02)....................................................................................62 Bones , joints and the skeleton (BO 03)...................................................................................63 Estimation of skeletal mass (BO 04) ........................................................................................63 Structure of a synovial joint (BO 05)........................................................................................64 Summary Table .....................................................................................................................................66

SECTION 2: SCIENCE CENTRES...............................................................................................................70 4

Ontario Science Centre, Canada ..............................................................................................70 Science Museum (London) ......................................................................................................71 Natural History Museum (London) ..........................................................................................71 Glasgow Science Centre...........................................................................................................71 Birmingham Science Centre ‘ThinkTank’ .................................................................................74

SECTION 3: SCIENCE FESTIVALS ............................................................................................................76 Edinburgh Science Festival.......................................................................................................76 The Big Bang Science Festival .................................................................................................. 76 British Science Festival.............................................................................................................76

SECTION 4: SCIENCE OUTREACH...........................................................................................................77 Science Live ..............................................................................................................................77 The Inspire Discovery Centre (Norwich) ..................................................................................77 The Science Museum (London)................................................................................................77 The Discovery Zone at Leeds University ..................................................................................78 University of Bristol: Physiology Teaching Lorry......................................................................78 The Human Performance Unit, University of Essex.................................................................78 Science and Engineering week.................................................................................................79 Wellcome Trust Moving Bodies Event .....................................................................................79

Appendices............................................................................................................................................81 1.

Commonly used equipment..................................................................................................81

2.

Pictures from the Science Centres ........................................... Error! Bookmark not defined.

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Acknowledgments Thanks to colleagues from the Physiological Society, particularly Dr Christabel Stokes. Thanks also to colleagues who sent practical outlines from: University College Chichester, University of Cardiff, University of Essex, University of Nottingham, University of Leicester, University of Leeds, University of Portsmouth, University of Swansea, & University of Strathclyde. We also would like to thank ADInstruments for their assistance The following books were of particular help: Exercise Physiology Laboratory Manual, 1990, (2nd Edition) Gene M Adams, publishers; Brown & Benchmark, Wisconsin, US Kinathropometry and Exercise Physiology Lab Manual: Tests , Procedures and Data, Volume 1: Anthropometry, 2001, (2nd Edition) Roger Eston and Thomas Reilly, publishers; Routledge, London Kinathropometry and Exercise Physiology Lab Manual: Tests , Procedures and Data, Volume 2: Exercise Physiology, 2001, (2nd Edition) Roger Eston and Thomas Reilly, publishers; Routledge, London All internet sites were accessed between June 14th and July 13th 2010.

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List of abbreviations 1RM: 1 repetition maximum ATPS: atmospheric temperature and pressure saturated bpm: beats per minute BP: blood pressure (mmHg) CO2: carbon dioxide CV: cardiovascular EMG: Electro myogram EPOC: Excess post-exercise oxygen consumption FEV1. Forced expiratory volume in 1 second (L) FVC: forced vital capacity (L) HRM: heart rate monitor iRMS: Root mean squared (current) MAOD: maximum accumulated oxygen deficit mph: miles per hour MVC: Maximal voluntary contraction OBLA: onset of blood lactate accumulation O2: oxygen ROM: Range of motion RPE: Rate of perceived exertion RPM: Revolutions per minute RMR: Resting metabolic rate STPD: standard temperature and pressure dry TEE: total energy expenditure VE: volume of air expired (L) VO2 : volume of oxygen used at any given time VO2 max: maximum volume of oxygen used at any given time W: Watts

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SECTION 1: UNDERGRADUATE PHYSIOLOGY EXPERIMENTS Experiments in this section have been placed into one of the five categories (Blood, Breath, Brain, Brawn and Bone) according to their primary purpose. Where an experiment may cross into other categories is highlighted in the summary table at the end of section 1. Each experiment is ranked in terms of difficulty level: Low/Moderate/High Low: Easy for young children to understand the protocol and to take part in the measurements. Moderate: requires a greater level of skill to understand and carry out the measurements. Pupils would be able to join in as participants and assist in data collection. High: difficult to carry out the experiments and may be suitable only for demonstration purposes in most schools

Each experiment is also ranked in terms of equipment required to carry out the full protocol: Equipment required level: Basic/Intermediate/advanced Basic: readily available in schools or easy to transport to schools and be used by teachers Intermediate: may require some specialist equipment and a limited amount of technical knowledge. Pupils would be able to join in as participants and assist in data collection Advanced: requires both technical knowledge and equipment. Likely only for demonstration purposes in most schools As much as possible, within each physiological subsection, the experiments are ordered with the low difficulty level protocols coming first, and the high difficulty protocols coming later.

Factors affecting the experiments: All of the tests can be manipulated to make exciting and fun experiments, especially as the participants find more about themselves and fellow class-mates. They could also compare themselves against others nationally or even worldwide (for example the Human Performance Unit at University of Essex holds data of high school pupils from various fitness tests- (see Section 4 and www.humanperformanceunit.co.uk ).

During activity the whole body is working in unison: the heart, the lungs, the muscles, the brain and nerves, and the bones. Although the tests listed here are in sections, it is important to remember that no one physiological system works in isolation.

Exercise brings about short-term changes in breathing (the lungs), the cardiovascular system (the heart and blood vessels) and the muscular skeletal system, with messages from the brain playing a role. These changes can be measured during and after exercise and the results recorded and compared to before exercise. 8

Different factors affect the response to exercise, and therefore the results of any test: 1. Altering the exercise itself a. Duration b. Intensity c. Type of exercise d. The use of a different body parts 2. Altering the environment a. Temperature/humidity b. Within a laboratory setting / in the ‘field’ 3. Individual responses a. Gender b. Age c. Fitness d. Muscle strength and endurance e. Flexibility f.

Body fat

g. Hydration status h. Ability to get rid of excess heat i.

Genetics (important in determining some of the above)

Normal values for some tests have been included where relevant. However, as normal values are often dependent on age, weight, gender and height not all values have been given.

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1.1 Physiology sub-section: BLOOD The blood is vital for carrying oxygen (in the haemoglobin) to the muscles to produce energy and for carrying carbon dioxide back to the lungs. By measuring heart rate and oxygen levels, it is easy to determine how hard the body is working.

Heart rate (how fast the heart is beating) can be measured by counting the pulse at the wrist or neck, or can be measured by a heart rate monitor (which fits around the chest). For more detailed information about the heart, an ECG (electrocardiogram) can be taken. This provides information about the electrical activity in the heart. The picture below shows a healthy ECG trace. The trace is labelled (P, QRS, and T), relating to electrical activity in different chambers of the heart, namely the atria and the ventricles.

A stethoscope can be used to listen to the different heart sounds: contraction (systole) when the blood is pushed out of the heart; and when it is relaxed (diastole). Blood pressure can be measured by using various blood pressure monitors (manual, including stethoscope and sphygmomanometer, or digital). Two numbers are usually given: systolic (the highest pressure) and diastolic (the lowest pressure) i.e. 120/80mmHg (which is normal blood pressure in adults. Children’s blood pressure is usually lower and is dependent on height as well as age). During rhythmic exercise (such as walking or cycling) the systolic pressure usually increases whilst the diastolic pressure stays at a similar level. During strenuous exercise, such as weight lifting, both the systolic and diastolic values increase.

Exercise capacity is a commonly measured variable in human physiology. To carry out long duration exercise, the body needs lots of oxygen. The amount of oxygen that a person uses can be easily measured, by collecting the air they breathe out and comparing it with the air they breathe in. The maximum amount of oxygen a person can use is called their VO2 max. In general, fitter people have a higher VO2 max. The average is around 35-40 ml kg-1 min-1, but this can get up as high as 90 ml kg-1 min-1 in very fit individuals. Measuring VO2 max can be done via various methods: 1. within a laboratory (treadmill, bike) or field methods (Bleep test, step test, Coopers run) 2. direct methods (using gas analysis) or indirect /predicted i.e. measure heart rate and workloads and calculate using nomograms or equations. A nomogram is a visual representation of an equation. The user finds their relevant values (e.g. heart rate and 10

power output) on a chart, and determines their VO2 max by drawing a straight line between them. Equations such as the Haldane transformation or the YMCA equation allow the individual to enter their own values from the test, and determine a VO2 max. 3. using maximal exertion tests or sub-maximal tests (i.e. not to maximal effort)

Fitness is commonly defined by what is known as maximal oxygen uptake (usually written as VO2 max). This is how well the person can use oxygen (O2) to produce energy. This is dependent on: a. Lungs: size, blood supply, ability to get air in b. Heart: size, strength, rate c. Blood: volume and oxygen carrying capacity (haemoglobin) d. Blood vessels: from large (arteries) to the very smallest (capillaries) at the muscle e. Muscle: efficiency of extracting oxygen, size of muscle

The body’s response to exercise depends on the exact nature of the exercise. Low to moderate intensity rhythmic exercise (such as cycling or jogging) results in increased heart rate, increase in oxygen uptake, increase carbon dioxide production, increased systolic blood pressure and stable diastolic blood pressure. There is unlikely to be a large increase in lactate levels. Conversely, short duration but high intensity exercise (such as 100m sprint) uses up little oxygen but produces lactate. Lactate in the blood can be measured with just a small pinprick at the finger. Fit individuals can work at a higher intensity of exercise before the lactate levels in their blood start rising. The body ‘re-cycles’ lactate quite well at low levels, but once there is more than about 4mmol lactate present, it starts to accumulate at a rapid rate if exercise continues.

Also see the section on ‘breath’ for details of energy production and the use of oxygen. …………………………………………………..

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Predicting VO2 max using the 20m shuttle run (Bleep Test) (BL 01) Source: University of Essex Difficulty level: Low Equipment level: Basic (20m shuttle CD and player) Aim: Predict maximum oxygen uptake from a maximal field test Brief summary of methods: Participants run a 20m course in time with audible ‘beeps’. Every minute, the speed required to maintain the correct pace increases. Participants continue until they can no longer maintain the required speed. Final shuttle number is converted to VO2 max using the prediction equation. …………………………………………………..

Predicting VO2 max using the Forestry Step test (BL 02) Source: University of Essex Difficulty level: Low Equipment level: Basic (Steps/platform of appropriate height (40cm for males and 33 cm for females), metronome) Aim: To predict maximal oxygen uptake from a sub-maximal field test Brief summary of methods: Record body weight measurement in the clothing to be used for the test. The metronome is set at 90 beats per minute, to indicate the stepping rate of 22.5 steps per minute. The participant steps up and down on the step, leading with either leg. Males are to use a higher step than females. After five minutes of stepping, the participant sits down and a heart rate measurement is taken. Count the number of heart beats, starting from 15 seconds after completing the test, and stop counting 15 seconds later at 30 seconds post-exercise. You can count heart beats manually or use a HRM. Estimate VO2 max from set tables. …………………………………………………..

Predicting VO2 max using the Harvard Step test (BL 03) Source: University of Leicester Difficulty level: Low Equipment required level: Basic (Step, stopwatch) Aim: To estimate aerobic fitness via heart rate recovery Brief summary of methods: 1. Sit quietly for 3 minutes 2. Measure baseline heart rate (HR) (manually or using HRM) 3. Step test - 3 minutes, step on and off the steps Left foot up, right foot up, left foot down, right foot down Using the rhythm of the metronome begin stepping at 24 step cycles/minute, a total of 72 steps 4. Measure HR each minute for 3 mins immediately after the step test 5. Circle your heart rate level in the chart below : 12

Heart rate at 1 minute post exercise (HR1) Male Excellent 106

Female 118

Fitness levels can be calculated using the following formula Result = 30000 ÷ (HR1 + HR2 + HR3) Excellent Male >90 Female >86

Above Average 80-90 76-86

Average 65-79 61-75

Below Average 55-64 50-60

Poor