Endurance Physiology

Exercise physiology is the general study of the physiological effects of exercise and the specific study of the body’s unique responses to training.  This section is devoted to exploring the intricacies of how the human body works in relation to endurance performance.

Performance Explained – Introducing the Power Running Model of Endurance Physiology  Have you ever wondered just why you can’t run faster?  What is going on in your body that determines how fast you can run for any distance?  This article explains, in plain language, the physiological things that determine how fast you can run.  If you don’t really care about all the physiological jargon and endless debate about things like mitochondrial density or VO2max and you just want to know in general terms how all that physiological stuff fits together this article is for you.

Do High Lactate Concentrations Actually Improve Performance?  If you read popular running books or magazines you have most likely been exposed to the term lactate threshold.  Those books and magazines have likely advised you that in order to improve your distance running performance that you need to improve your lactate threshold.  What is lactate and what is the lactate threshold?  Why are you told that improving your lactate threshold is important in running performance?  In this article we will discuss the traditional role that lactate has believed to have played in endurance performance, explain the concept of lactate threshold, and then review the latest research on lactate’s influence on endurance performance.

A physiological explanation for 30 years of marathon training advice  The Jan/Feb 2007 issue of Running Times magazine (RT) contained a very interesting article by Jonathan Beverly titled “30 Years of Marathon Training”. In this article Jonathan examined the marathon training advice printed in Running Times over the previous 30 years to see what core principles he might discover.  His review provided some thought provoking findings.  Here’s the link to the article.

Central Governor Model – part 1  A review of Prof Noakes’ revolutionary model of endurance performance.

Central Governor Model – part 2  A review of Prof Noakes’ revolutionary model of endurance performance.

Do increases in VO2max cause performance to improve?  If you have read any popular literature then you’ve heard that increasing your VO2max is an important goal of training because a higher VO2max causes performance to improve.  Is that really true?  Does an increasing VO2max = improved performance?  Find out what the research has to say in this article.

How much can you improve?   You just took up running and are excited about your new activity.  You’ve taken care of the necessary stuff – bought a good pair of running shoes, purchased running specific clothing, and scouted the best places to run in your town and neighborhood.  You’ve gotten over the initial aches and pains that cropped up when you first started running so that now your workouts are quite enjoyable.  Naturally, your thoughts then turn to wondering just how much you can improve; how fast you can get.  What are the odds that there is elite level talent lurking in your genetic structure?  Or above average talent?  Is there any way to determine this in advance?  That’s our topic today – just how much can you expect to improve and what are the odds that you will be a great runner?  Probably not surprising, scientists have wondered the same thing and have conducted research to answer this same question.  This research provides some reliable data for us to consider, data that may really surprise you.

Part 1          Part 2          Part 3

How different are Elites?  Are there measurable differences between untrained muscles in elite runners and non-runners?  I suggest that there are inborn (genetic) differences in the muscles of elite runners that allow them to perform as they do.  If this is true, it is likely that these differences can be measured – that untrained muscles of elite runners will be measurably different than the same muscles in untrained subjects.  This topic has been studied by researchers in an effort to determine if differences in performance between elites and average runners have a genetic component.  Read the article here.

Muscle fiber activation and aerobic base building  The most frequent physiological reason cited for the necessity of base building is that it maximizes the aerobic capacity of the slow twitch fibers.  Does the research support this claim?  Find out in this article.

The Surprising Aerobic Benefit of Sprinting  If you’ve been involved in running for any length of time you have surely been exposed to the concepts of aerobic and anaerobic training.  These two terms are firmly entrenched in the running community, having been in use for more than 50 years.  So strong is the belief in the concept of aerobic and anaerobic training zones that some programs are founded on the distinction between these two types of training.  But is the belief in “aerobic” and “anaerobic” supported by the research?   New studies reveal some interesting data.

More Research on the Aerobic Benefit of Sprinting  In the article The Surprising Aerobic Benefit of Sprinting I reviewed a unique study that showed that a sprint only training program resulted in some surprising aerobic benefits.  Following the publishing of that study the same research team performed additional follow-on studies examining the surprising endurance benefit of sprint training.  Two of these follow-on studies provide additional insight into “aerobic” physiological and performance changes caused by sprint training.

Muscles Limit Performance  Based on the available research I believe that muscles exert the strongest influence on endurance performance.  In this article I will attempt to prove that muscles, not oxygen, are ultimately responsible for your endurance performance.  This is a tall order because, for must runners, this idea opposes everything they’ve ever been taught.  But, if you will set aside preconceived notions I think you will find the evidence compelling.

Running Physiology  If you’ve read much about the subject of running, you are probably aware that most modern training programs are very similar.  The current thought on how to best train could be summed up with the slogan “run more”.  Certainly each training program has its particular nuances, but the overall theme of modern training programs is that in order to run better, you should run more.  This means that if you are currently running 25 miles a week, then by increasing your weekly mileage to 40 miles a week you will improve your performance.  If you are already at 40 miles a week, then up it to 60.  And so on, and so on.

Where did this philosophy originate?  And even more important, is it accurate?  Is increasing volume the best way to improve your performance?  Despite the popularity of the “more is better” approach, is there an alternate training approach that would yield superior results?  These are the kinds of questions we will be addressing in this 7 part series on the current state of the art in running physiology.

Part 1          Part 2          Part 3          Part 4          Part 5          Part 6          Part 7      

Muscle Contractility  In the article “Muscles Limit Performance” I built the case that your muscles are the primary determining factor in your running performance.  Since we have now established that fact, you are probably asking for more specifics.  What specifically about my muscles limits performance?  What is the best kind of training to conduct in order to improve my muscles?  These are the questions we will answer in this series.

Muscle Contractility part 2 – speed of contraction

Muscle Contractility part 3 – strength

Muscle Contractility part 4 – fatigue resistance

Muscle Factors   I have termed my training program and the physiological beliefs supporting them “power running” because I believe that muscle factors are primarily responsible for endurance performance.  This belief in the primacy of muscle factors stands in stark contrast to the long-held belief that the aerobic system is the dominant influencer of endurance performance.   I’ve written extensively about these muscle factors and the multiple research studies supporting my beliefs that muscles exert the most influence on endurance performance.  To the best of my knowledge I have been the sole proponent of these ideas for the past few years.  Today it appears I am no longer alone in promoting the influence muscle factors play in endurance performance.  Read the article here.

How does a foundational myth become sacred scientific dogma?  The Case of A.V. Hill and the anaerobiosis controversy.  by Professor Tim Noakes

Part 1           Part 2          Part 3              Part 4           Part 5

The Physiology of Base Building  Base building proponents often use physiological reasons to explain their recommendation for base building.  Does the cited physiological research actually support the claims of base building advocates?  Can base building be justified on the basis of physiological research?  This article examines the research most often cited by those recommending base building.

The Physiology of FIRST  Since 2003 two marathon running and ironman triathlete exercise physiolgists at Furman University have recommended a unique training program they call FIRST training.  The FIRST training method has received a lot of attention from the running community because the research data shows that more than 70% of the experienced runners who participated in the three FIRST marathon training research studies set personal records or beat their most recent performance in the marathon.  Clearly, the FIRST training program has been very successful for a large majority of those who tried it.  What is the physiological explanation offered by the Furman team for the success of the the FIRST program?  Why does it work and why does it work better than other programs?  This article examines the physiology of FIRST.

Only a Difference of Magnitude  In 2005 exercise scientist Dr. Ed Coyle of the University of Texas published a research study based on seven years of physiological data collected on Lance Armstrong (1).  During the seven years covered by the study Lance improved from a young, just-turned-professional, cyclist to “best in the world” and multiple winner of the Tour de France.  What physiological changes accounted for the improvement in Lance’s performance?

Popular Press and Lactic Acid  If you read popular running books and/or magazines you have undoubtedly been exposed to the idea of “lactate threshold”.  Basically, this belief posits that an increase in lactate levels within the muscle cells increases acidity within the muscle, resulting in fatigue.  This belief in the fatigue causing nature of lactate is firmly entrenched in current training programs, with most programs including training methods to “improve the lactate threshold” or the pace that can be maintained without an excessive accumulation of lactate within the body.  However, there has been an ever increasing volume of research that challenges the belief in a “lactate threshold”.  This article examines the latest thought on the lactate threshold and the nature of fatigue.

The Effect of Training Frequency on Recovery  Perhaps the most frequent protest that I hear against a high quality, low volume training approach is that “elites run high mileage, thus proving that high mileage is the best training method”.  I agree that elites train using high volume.  For many, that is proof enough that high volume is the best training method.  However, the path from “all elites train with high volume” to “therefore, it’s the best training method for everyone” is not as short or straightforward as you might think.  Is high mileage necessary in order to maximize performance?  This article looks at the available research on the topic.

Dose-Response and Running  Are you familiar with the concept of dose-response?  It is used in the medical world to describe the relationship between the dose and response to a drug.  However, it is a concept that equally applies to all types of athletic training, including running and has much to teach us. Learn more in this article.