Advanced Neuromuscular Exercise Physiology

Chapter 1. Muscle Fibers, Motor Units, and Motoneurons
Muscle Heterogeneity
Orderly Motor Unit Recruitment
Smaller Motoneurons Are More Excitable
Membrane Resistivity and Motoneuron Size
Other Factors Determining Action Potential Generation
Minimal Firing Rates and Afterhyperpolarization Durations
Motoneuron Current–Frequency Relationship and Excitability
Spike Frequency Adaptation
Motoneuron Persistent Inward Currents (PICs)
Summary

Chapter 2. Motor Unit Recruitment During Different Types of Movements
Measuring Human Motor Unit Recruitment
Influence of Task
Synergists
Influence of Pain on Motor Unit Recruitment
Slow-Ramp Isometric Contractions
Maintained Isometric Contractions
Isometric Contractions in Various Directions
Isometric Contractions Versus Movements
Ballistic Contractions
Lengthening Contractions
Cocontraction of Agonists and Antagonists
Unilateral Versus Bilateral Contractions
Maximal Voluntary Contractions
Muscle Histochemistry to Investigate Rhythmic Complex Contractions
Summary

Chapter 3. Muscle Blood Flow and Metabolism
Muscle Blood Flow
Muscle Metabolism
Summary

Chapter 4. Peripheral Factors in Neuromuscular Fatigue
Fatigue as Interference With the Contractile Machinery
Failure of Impulse Propagation Along the Muscle Fiber Membrane
Peripheral Fatigue Sites Other Than Muscle Membrane and Contractile Machinery
Research From Animal Experiments
Summary

Chapter 5. Central Factors in Neuromuscular Fatigue
Motoneuron Activity During Sustained Contractions
Isometric Versus Anisometric Tasks
Rotation of Motor Units?
Summary

Chapter 6. Muscular Mechanisms in Aerobic Endurance Training
Chronic Muscle Stimulation
Coordination of Muscle Protein Systems
Pretranslational Control
Translational Control
Posttranslational Modifications
Mitochondrial Responses
Simultaneous Expression of Isoforms
Adaptations Can Occur Ex Vivo
Adaptations Appear in a Specific Sequence
Thresholds of Activity for Adaptation
Chronic Stimulation and Atrophy
Metabolic Signals and the Adaptive Response
Degenerative and Regenerative Processes
Summary

Chapter 7. Neural Mechanisms in Aerobic Endurance Training
Adaptation of the Neuromuscular Junction
Responses of Motoneurons
Adaptations of Spinal Cord Circuits
Summary

Chapter 8. Muscle Molecular Mechanisms in Strength Training
Acute Responses in Protein Synthesis and Degradation
Connective Tissue Responses
Role of Muscle Damage
Role of Dietary Supplements
Summary

Chapter 9. Muscle Property Changes in Strength Training
Increased Muscle Fiber Cross-Sectional Area
Fiber Type Composition
Muscle Fiber Number
Muscle Composition
Muscle Architecture
Muscle Fiber Ultrastructure
Tendons
Evoked Isometric Contractile Properties
Changes in Muscle Force, Velocity, and Power
Fatigue Resistance
Role of Eccentric Contractions
Concurrent Resistance and Aerobic Training
Summary

Chapter 10. Neural Mechanisms in Strength Training
Gains in Strength Versus Muscle Girth
Strength Gains Show Task Specificity
Surface EMG Response During MVC
Imaginary Strength Training
Reflex Adaptations
Cross Education
Decreased Activation of Antagonists
Changes in Motor Unit Recruitment
Changes in Motor Cortex
Summary

Chapter 11. Clinical Considerations Concerning Neuromuscular Exercise and Training
Effects of Exercise on Neuromuscular Aging
Effects of Exercise Training in Stroke Patients
Physical Activity and Fibromyalgia
Exercise and Dementia
Amyotrophic Lateral Sclerosis
Summary

Advanced Neuromuscular Exercise Physiology, Second Edition, uses a mix of biochemistry, molecular biology, neurophysiology, and muscle physiology to provide a synthesis of knowledge and research in the field. The text is a leading resource devoted solely to the topic of nervous and neuromuscular systems, and it assists readers in identifying current directions in research and new avenues for exploration.

Advanced Neuromuscular Exercise Physiology, Second Edition, offers readers a foundation of knowledge while detailing the most recent findings in the rapidly changing field of neuromuscular exercise physiology. It simplifies complex concepts with illustrations and graphs—including 20 new figures—all showcased in a new larger format to help students visualize and better understand the material. A new chapter on clinical considerations has been added, focusing on conditions that involve a compromise in the neuromuscular mechanisms necessary for movement. Other chapters have been updated with new or expanded content, including the following topics:

• Blood flow restriction during exercise as a training method
• The influence of pain on motor unit recruitment
• Surface EMG signals and the role that high-density surface EMG has played in motor unit recruitment research
• Updates on the role of the motoneuronal initial segment in the activation and adaptation of motoneurons
• An exploration of the “onion skin” pattern and neuromechanical matching for an explanation of motor unit recruitment
• The role of exerkines and small extracellular vesicles in adaptation to exercise

The text covers a variety of important issues in the field, beginning with a discussion of motor unit types, muscle blood flow, and metabolic pathways in control of metabolism. Possible peripheral and central contributors to fatigue are discussed, as well as the effects of aerobic endurance training and strength training on the protein profiles of muscle fibers and on the central nervous system.

Chapter objectives have been added to the text to provide a road map for the readers, and new review questions help students assess their understanding of the content. Chapter summaries recap the key issues presented for each topic. Analyses of research findings and research applications are highlighted in special sidebars. Throughout the text, practical examples help readers engage with the content.

Within the dynamic field of neuromuscular exercise physiology, ideas of how nerves and muscles collaborate during acute and chronic exercise are continually evolving. Advanced Neuromuscular Exercise Physiology, Second Edition, offers an authoritative perspective of current research in the field as it seeks to encourage discussion, further study, and new research directions.

Phillip F. Gardiner, PhD, is a professor emeritus of kinesiology and recreation management at the University of Manitoba, with a cross-appointment in the department of physiology and pathophysiology in the Rady Faculty of Health Sciences. He served as director of the Spinal Cord Research Centre at the University of Manitoba from 2015 to 2020 and prior to that was the director of the Health, Leisure, & Human Performance Research Institute.

Author of the Human Kinetics books Neuromuscular Aspects of Physical Activity (2001) and Skeletal Muscle: Form and Function (coauthor, 2006), Gardiner has also published over 150 research articles on neuromuscular system adaptability.

Gardiner served as the president of the Canadian Society for Exercise Physiology (CSEP) and as coeditor in chief of the Canadian Journal of Applied Physiology. In 2007, he received the highest award bestowed by the Canadian Society for Exercise Physiology: the CSEP Honour Award. He served as a Tier I Canada Research Chair in physical activity and health studies at the University of Manitoba from 2002 to 2016 and was chair of the Scientific Committee of Muscular Dystrophy Canada from 2015 to 2018. He has also served the Canadian Institutes of Health Research as chair of the board and as scientific director of the Institute of Musculoskeletal Health and Arthritis (IMHA).