Book review: Exercise physiology, by McArdle, Katch and Katch

After receiving many pleasant comments and emails for the work I did in 2011, I felt under no small amount of pressure to perform in 2012.  So let’s start as we mean to go on with some heavy lifting.  And when it comes to book reviews, they don’t come much heavier than Exercise Physiology, by McArdle, Katch and Katch, the industry standard work (affiliate links: UK, US).

The heavy lifter’s bible for understanding the basics

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So what is it about?

It’s a basic explanation of all the key issues relating to physical activity.  It covers the following subject headings:

• Nutrition
• Macronutrients
• Vitamins, minerals and water
• Optimal nutrition for exercise
• Energy
• Energy value of food
• Introduction to energy transfer
• Energy transfer in the body
• Measurement of energy transfer
• Energy expenditure during rest and activity
• Energy activity during walking, jogging, running and swimming
• Individual differences
• Energy systems
• Pulmonary structure and function
• Gas exchange
• Dynamics of pulmonary ventilation
• The cardiovascular system
• Cardiovascular regulation
• Functional capacity of the cardiovascular system
• Skeletal muscle: structure and function
• Neural control of human movement
• The endocrine system and exercise
• Training the energy systems
• Training for aerobic and anaerobic power
• Muscular strength
• Special aids to strength and conditioning
• Exercise and environmental stress
• Exercise at altitude
• Exercise and thermal stress
• Sport diving
• Body composition and health
• Assessment of body composition
• Physique and physical activity
• Obesity and weight control
• Physical activity, health and ageing
• Clinical exercise physiology for rehabilitation

However, while the breadth of material covered is wide, it is important to be careful in our approach.  As a reference book, the material is often summarised and (depending on how old your edition is) has often been superceded by more recent research.

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Nutrition

The nutrition section gives you a basic grounding in the information and issues that nutritionists and scientists have been arguing about for decades.  Along the way, prepare to be severely warned in no uncertain terms about the dangers of saturated fat for heart disease.

Of course, this all sounds counter-intuitive to the rational mind familiar with modern research in these areas.  After all, we know from books like Dr Malcolm Kendrick’s The Great Cholesterol Con that saturated fat intake has nothing to do with heart disease.  Incidentally, one of the researchers that Dr Kendrick refers to is a Dane called Uffe Ravnskov.  And, recently, I spent some more time reading through Ravnskov’s work and came across the following interesting study.

In his paper, The Questionable Role of Saturated and Polyunsaturated Fatty Acids in Cardiovascular Disease, by Uffe Ravnskov, Journal of Clinical Epidemology, 1998, Ravnskov reviewed 112 different scientific studies, including a number of studies that looked at whole countries, just like Ancel Keys did.

Ravnskov presented a chart summarising those country-wide studies as follows.  The x-axis shows the percentage of saturated fat people in that country are eating and the y-axis shows the overall mortality.  You can see for yourself that there is no connection whatsoever.  The data is just a collection of random dots.

Uffe notes that in his review, he found just one single cross-sectional study, three cohort studies, and one lone trial were supportive of the Diet-Heart hypothesis.  On the other hand, all studies of the secular trends, more than 50 cross-sectional and cohort studies, and eight trials were unsupportive (i.e. showed it was false).  By sheer weight of numbers, this suggests that we should abandon the idea that saturated fat causes heart disease.

Uffe concludes: “there is little evidence that saturated fats as a group are harmful or that polyunsaturated fats as a group are beneficial.”

However, this does not mean that the nutrition section in the book is useless, it is merely a useful reminder that textbooks tend to be written by venerated old professors and are usually decades behind their time when it comes to the big issues of their day.  Treating these sections as records of the historical debate rather than reflective of some absolute truth is essential to making the best use of them.

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Energy

The section on energy takes us naturally from the nutrition section through to the energy systems section.  It begins by explaining the measurement of energy in food by calories and then discusses how each of the macronutrients are digested by the body.  From there, we discuss the oxidation of glucose, triglycerides and glycerol by the various mechanisms in aerobic and anaerobic glycolysis.  After that, we move on to a discussion of the various pathways in which the body powers its activities: the creatine-phosphate system, the lactate system and the aerobic system.

At this point, we have to wade carefully through a discussion of oxygen debt and the relationship between aerobic and anerobic energy systems, knowing that our understanding of the way in which the lactate system works has since been seriously overhauled by the work of George Brooks and his lactate shuttle theory of the anaerobic system.  For further details on this, check out my articles:

• Intra and extra cellular lactate shuttles, an update from George Brooks about his most recent research, and
• Anaerobic threshold: concept and methods of measurement, a discussion of the concept of the anaerobic and aerobic systems.

As we come to the end of the energy section, we review the various energy requirements of walking, jogging, running and swimming and again exercise caution during a discussion of running economy.  Unfortunately, there is little discussion of resistance training for improving economy, but you can read more about that in my review articles:

• Factors affecting running economy in distance runners, which notes that running economy is one of the most important factors in predicting running performance, even more than cardiovascular capacity (VO2-max), and
• Interrelationships between muscle structure and running economy, which discusses how running economy is related to muscle fibre type and the types of contractile proteins in the muscle fibres

However, we do find concern expressed about the fact that running shoes are clearly adverse as far as running economy is concerned, as they dampen the transfer of force between the foot and the ground and add unnecessary weight to the runner.  Neither of these things are desirable from a purely mechanical point of view.

As you might expect, our textbook comes down on the side that the shoe is required for stability and foot protection.  Of course, we now know that this whole idea is upside down, as various investigations into barefoot running and the incidence of injury with and without running shoes has now more recently demonstrated.

Again, this merely underlines the importance of treating the textbook as a record of historical debate and not as the complete story.  It also makes a good case for staying up-to-date with recent research.

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Energy systems

The energy systems section is the real meat and potatoes of the book as far as exercise enthusiasts, strength trainees and personal trainers are concerned.

Kicking off with a discussion of the pulmonary structure and function, we romp through the function of the lungs in exchanging oxygen and carbon dioxide and work our way through the cardiovascular system, discussing various issues (including limiting factors) before arriving at a discussion of skeletal muscle and finishing up with two very good chapters, on the neural control of human movement and the endocrine system and exercise.

As an aside here, an interesting point on limiting factors is that many people regard the fact that the body reaches a ventilatory threshold as indicative of the fact that oxygen is not a limiting factor in aerobic respiration.  Until recently, I therefore assumed that (except for swimmers who have a need to perform with limited breathing) there was therefore no need for us to train athletes to be able to breathe harder or faster.  However, I recently read an interesting article about improving the inspiratory muscles for cycling.

In this very interesting study, Effects of inspiratory muscle training on time-trial performance in trained cyclists, by Romer, McConnell and Jones, Journal of Sports Science, 2002, the researchers found that they could improve the time trial performances, the tidal volume and the perception of effort at a given workload by training the inspiratory muscles of cyclists.

Anyway, back on track, if you are not normally given to reading much around exercise physiology, but are comfortable with the basics of cardiovascular exercise and muscular function, then just reading these last two chapters will significant improve your knowledge base.  They are exceptionally good, thorough and helpful guides to understanding these two specific areas.

In particular, the section on the endocrine system will be particularly helpful if you want to get further into how stress works, how stress can make you fat and why it is important to manage it as part of your recovery from training.

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Training the energy systems

The training section usefully outlines all of the adaptations to cardiovascular and muscular training that occur in the body.  However, there is no significant discussion of detailed training progressions or theories of developing elite-level strength or power, as in Zatsiorsky.

There is, however, an amusing section in my copy on artificial steroids that makes the outlandish claim that there is doubt regarding their efficacy.  I bet the authors still turn in their beds about that one.

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Exercise and environmental stress

For those athletes interested in exercising at altitude or competing in extremely hot environments, such as desert races, this section will be useful.

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Body composition and health

The final section discusses body composition (i.e. how fat you are) and explains how to make an assessment of body composition using various different tools, gives some measuring sticks regarding the average body composition of athletes in various sports, and discusses the general trend towards obesity in the general population and the difficulties of dieting.

Unfortunately, there is no discussion of obesity in relation to stress, which I consider is extremely important for any debate about weight-loss in the 21st Century.

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Summary

In summary, this is a very useful reference tool for filling in any small gaps in your knowledge.  I find it invaluable when I am reading a piece of research and I suddenly come across a term or concept that I am not familiar with.  A quick hunt through the index and I can generally get a good but simple overview that sets the term in context.

It’s not going to take your knowledge to the next level in any specific area that you are interested in because it’s an introductory text.  So don’t go rummaging through it trying to see whether it discusses Eastern Bloc Training in detail or the difficulties in programming for the development of speed-strength because it doesn’t.  It’s a reference work rather than a subject-specific text.

Finally, if you are studying for a personal training qualification, it will probably be more advanced that the material you are learning.  So (paradoxically) it will make more sense than the booklet you have been given because it won’t have half of the material cut out.  I found it very helpful when I was studying for my personal training qualification and it made me relatively popular in my class for providing proper answers to the various questions that came up as we were going through the course.