Engineering Physiology (eBook)

A Few Words at the Beginning 5
About References in This Edition 6
We Would Like to Hear from You! 6
Contents 7
List of Figures 14
List of Tables 19
1 Skeletal Structures 22
Overview 22
The Model 22
Introduction 22
Bones 23
Cartilage 25
Tendons and Ligaments 25
Articulations 26
Mobility 29
Artificial Joints 32
The Hand 33
The Spinal Column 35
The Spinal Disk 39
Notes 41
Summary 42
Glossary 43
References 46
Further Reading 47
2 Muscles 48
Overview 48
The Model 48
Introduction 48
Muscle Architecture 49
Agonist-Antagonist, Co-contraction 49
Components of Muscle 50
Muscle Contraction 53
Relation Between Muscle Length and Tension 54
The ''Motor Unit'' 56
Muscle Twitch 57
Muscle Fatigue 57
Activities of Entire Muscles 59
Control of Muscle 59
Muscle Fiber Types 60
Strength of Muscle and Body Segment 60
Muscle Strength 62
Internal Transmission 62
Body (Segment) Strength 63
Exerting Strength with the Hand 64
Static and Dynamic Exertions 67
Static Strength 67
Dynamic Strength 68
Regulation of Strength Exertion 70
Feedforward 70
Feedback 72
Measuring Muscle Strength 72
The ''Maximal Voluntary Effort'' 72
Measurement Opportunities 73
Measuring via Feedforward 73
Measuring via Feedback 74
Measuring Output 74
Strength Measurement Devices 75
The Strength Test Protocol 75
Designing for Body Strength 77
Proper Statistical Use of Strength Data 78
Designing for Hand Strength 78
Using Tables of Exerted Torques and Forces 81
Designing for Foot Strength 82
Notes 88
Summary 89
Glossary 90
References 94
Further Reading 95
3 Neuromuscular Control 96
Overview 96
The Model 96
Introduction 96
Organization of the Nervous System 97
By Function 97
By Location 97
The Central Nervous System 98
Sensors and Effectors of the Peripheral Nervous System 99
The Nervous Pathways 102
The Neuron 103
Transmission of Nerve Signals 106
Control of Muscle 107
Ergonomic Engineering to Facilitate Control Actions 108
Notes 112
Summary 112
Glossary 113
References 117
Further Reading 117
4 Anthromechanics 118
Overview 118
The Model 118
Introduction 118
Stress and Strain 119
Mechanical Bases 120
Static Equilibrium 121
Dynamic Analyses 125
Anthropometric Inputs 126
Links and Joints 126
Body Volumes 127
Inertial Properties 131
Lean Body Mass 135
Locating the Center of Mass 135
Moments of Inertia 136
Kinematic Chain Models 136
Notes 139
Summary 140
Glossary 141
References 143
Further Reading 145
Journals: For Example 145
5 Respiration 146
Overview 146
The Model 146
Introduction 146
Architecture 147
Functions 149
Respiratory Volumes 150
Measurement Opportunities 151
Summary 151
Glossary 152
References and Further Reading 152
6 Circulation 153
Overview 153
The Model 153
Introduction 154
Body Fluids 154
Blood 154
Blood Groups 155
Functions 155
The Lymphatic System 156
The Circulatory System of the Blood 156
Architecture of the Circulatory System 156
The Heart as Pump 157
Cardiac Output 159
The Capillary Bed 160
Hemodynamics 163
Blood Vessels 163
Regulation of Circulation 165
Measurement Opportunities 166
Summary 166
Glossary 167
References and Further Reading 169
7 Metabolism 170
Overview 170
The Model: The “Human Energy Machine” 170
Introduction 171
Human Metabolism and Work 171
Energy Liberation in the Body 173
Energetic Reactions 174
The Pathways of Digestion 174
Energy Content of Nutrients 176
Absorption and Assimilation 179
Energy Release 180
Aerobic Metabolism of Glucose 180
Anaerobic Metabolism of Glucose 180
Metabolism of Carbohydrate 181
Metabolism of Fat and Protein 181
Energy Storage 182
Energy for Muscle Work 183
Release of Energy During a Strong Muscular Effort 184
Muscle Twitch 184
The First Few Seconds of Muscular Effort 185
The First Ten Seconds of Effort 185
Effort Longer than Ten Seconds 185
Muscular Work Lasting Minutes to Hours 185
Aerobic and Anaerobic Work 186
Energy Use and Body Weight 187
Notes 188
Summary 188
Glossary 189
References 190
Further Reading 190
8 Exercise and Work 191
Overview 191
The Model 191
Introduction 191
Capacity for Physical Exercise and Work 192
Diet and Weight Observation 192
Direct Calorimetry 193
Indirect Calorimetry 194
Assessment by Oxygen Consumption 194
Assessment by Heart Rate 195
Assessment by Subjective Rating of Perceived Effort 196
Standardized Tests 196
Bicycle, Treadmill and Step Tests 196
Challenges 197
Energy Requirements at Work 198
Procedures to Catalogue Metabolic Requirements 199
Basal Metabolism 199
Resting Metabolism 199
Work Metabolism 199
Techniques to Estimate Energy Requirements 202
Using Tables 202
Calculating 202
Light or Heavy Jobs? 205
Overall Changes in Body Functions in Response to Work Loads 206
Fatigue 207
Human Engineering/Ergonomics 208
Notes 209
Summary 210
Appendix 1: Techniques of Indirect Calorimetry 211
Appendix 2: Rating the Perceived Effort 212
Borg RPE Scale 213
Borg CR-10 Scale 214
Glossary 214
References 215
Further Reading 216
9 Thermal Environment 217
Overview 217
The Model 217
Introduction 217
The Human Body as a Thermo-Regulated System 218
The Energy Balance 218
Energy Exchanges with the Environment 219
Radiation Heat Exchange 219
Conduction Heat Exchange 221
Convection Heat Exchange 221
Evaporation Heat Exchange 222
Heat Balance 223
Regulation and Sensation of Temperature 224
Achieving Thermal Homeostasis 225
Measuring Body Temperatures 226
Assessing the Thermal Environment 228
Ambient Temperature 228
Air Humidity 228
Air Movement 228
Radiant Heat 229
The Combined Effects of Climate Factors 229
Reactions of the Body to Hot Environments 230
Redistribution of Blood 230
Reduction of Muscle Activities 231
Indications of Heat Strain 231
Acclimatization to Heat 233
Reactions of the Body to Cold Environments 234
Redistribution of Blood 234
Increased Metabolic Heat Production 235
How Cold Does it Feel? 236
Indications of Cold Strain 237
Acclimatization to Cold 238
Working in Heat or Cold 239
Effects of Heat 239
Cardiovascular Effects 239
Effects on Muscles 239
Dehydration 240
Effects on Mental Performance 240
Working in the Heat: Summary 240
Effects of Cold 241
Cardiovascular Effects 241
Effects on Body Temperature 242
Effects on Work Capacity 242
Dehydration 242
Effects on Mental Performance and Dexterity 243
Working in the Cold: Summary 243
Designing the Thermal Environment 243
Notes 246
Summary 246
Glossary 247
References 249
Further Reading 250
10 Body Rhythms and Work Schedules 251
Overview 251
The Model 251
Introduction 251
Menstrual Cycle 253
Circadian Rhythms 253
Models of Oscillatory Control 255
Individual Diurnal Performance Rhythms 256
Sleep 257
Sleep Phases 257
Sleep Loss and Tiredness 260
Normal Sleep Requirements 261
Sleep Deprivation and Prolonged Periods of Work 262
Performing Tasks 262
Incurring Performance Decrement and Recovering From It 263
Shift Work 263
The Development of Shift Work 264
Shift Systems 264
Flextime 267
Compressed Workweeks 267
Suitable Shift Systems 269
Health and Well-Being 270
Performance 271
Social Interactions 271
How to Select a Suitable Work System 272
Shift Length 274
Notes 276
Summary 277
Glossary 278
References 279
Further Reading 281
11 Engineering Anthropometry 282
Overview 282
The Model 282
Introduction 282
Measurement Techniques 283
Terminology and Standardization 283
Classical Measuring Techniques 284
New Measurement Methods 285
Body Typology 291
Anthropometric Data Sets 292
Normality 292
Variability 293
Correlations 296
Body Proportions 297
Variability of Anthropometric Data 300
Data Management 300
Secular Variations 302
Intra-individual Variations 304
Inter-individual Variations 304
Changing Populations 305
Available Body Size Data 309
How To Get Missing Data 309
Finding Data in the Literature 309
Conducting an Anthropometric Survey 312
Statistical Body Models 322
Deducing Unknown Values from Existing Data 323
Estimation by Ratio Scaling 323
Estimation by Regression Equation 324
Combining Anthropometric Data Sets 325
Two-Sample Composite Population 326
Using Anthropometric Data in Design 327
The ''Normative'' Adult 327
Body Positions and Motions at Work 328
Designing to Fit the Body 330
Determining Tariffs 332
Determining the Workspace of the Hands 332
Human-Centered Engineering 332
Notes 335
Summary 338
Glossary 338
References 344
Further Reading 347
Index 348