Fractional Utilization of VO2 Max (Lactate Threshold)

Fractional Utilization of VO2 Max (Lactate Threshold)

Lactate is a substance found in your body which plays a role in the metabolism to convert your energy stores into productive mechanical energy in your body.  Though different people have slightly more or less lactate, everyone can usually be found at rest around 1 mmol/L in the blood. When exercise begins, the amount of lactate in the blood starts to become effected. Though extremely gradual at first (perhaps unchanging for some), when the rate of carbohydrate utilization is elevated, the body cannot buffer out all the waste products creating higher levels of lactate accumulation in the blood. In other words, when an athlete is running slowly the majority of the energy which is being used is being taken care of in an efficient oxidative method which does not produce significant waste products to hinder performance. We have talked about this before in the “aerobic capacity” section earlier. When the running speed increases, the metabolism rate of that individual increases. Due to the need for high amounts of energy in this state, anaerobic glycolysis (rather than the more efficient oxidative phosphorylation) breaks down energy stores leaving significant waste products. When a high concentration of lactate is not transported in or out of cells quickly, accumulation of lactate occurs. A higher ph occurs as well due to static hydrogen ions which inhibit muscle contractions. This shows that the waste products, not the lactate alone, hinder the performance of the runner. This waste product, now referred to as lactic acid, as well as other factors (glycogen depletion, O2 flow, blood flow, etc) collectively, are the cause of muscular fatigue in runners.

Lactic acid often is felt significantly at the beginning of a training program because running form isn’t superior, MCTs 1 and 4’s expression is low, and Na/K pump expression is low. At the end of a training program often running form is more efficient, MCTs become lactate influx and effluxing engines and Na/K pumps in cells help resist against hydrogen ion build ups. In other words, your body both on the outside and inside becomes more efficient at dealing with lactic acid.

If someone were to ask me how to describe lactic acids effects in my own running I would tell them that from my perspective lactic acid fatigue is synonymous with pain management. Depending on the runner, different amounts of lactic acid in the body will force that individual to slow down. Phil Davies, a Sports Fitness Advisor, has said on his website, “It is thought that complete exhaustion occurs somewhere in the range of 20 – 25 mmol/L for most individuals although values greater than 30 mmol/L have been recorded.” Why are some people crippled at 20 mmols while others can maintain their form and confidence to continue? One of the more interesting things I have been exposed to lately is the idea of pain management. I just finished my last season of competitive collegiate cross country and I have looked back in hindsight at races that have been pivotal in my progression as a distance runner. I remember a 10k I ran during my first college track season where after running over 5 miles on a track (21 laps) I was able to accelerate my pace into 4:40 range with 4 laps to go. I felt fine during that lap, but WHAM it hit me. I could feel the accumulation of lactic acid shouting at me to slow down. I fought it the best I could and kept pushing. I felt as if I was maintaining that pace, but I realized that I was slowing down slightly. I threw in a final surge to kick off the last lap and finished that lap in 67 seconds completing the last 1600 in 4:59.

I remembered thinking after that race that when I decided to go as fast as I could there was something holding me back. What I believe now is that during these situations pain management becomes so important. Through years of workouts and race successes and failures I have learned that one of the reasons we train is to not only to train our body’s physiology but also our mental capacity to assure our body, during the race, that we have been through similar situations of pain and that this race or surge may hurt for a moment but will be ok.

There is a lactate threshold for all runners. Some runners can maintain a higher running speed, before lactate starts to accumulate, than others. It would be said that these individuals had a higher “lactate threshold” or LT. Lactate threshold is a very important factor for serious distance runners. When determining one’s lactate threshold a runner’s VO2Max is taken into account; hence the title to this section “Fractional Utilization of VO2 Max”. According to Tim Gibbons et al of the US Olympic Committee, “The [lactate turn-point] when expressed as a percentage of V02, is high in the endurance-trained athlete. In sedentary individuals, for example, the [lactate turn-point] may be at approximately 50-60% of VO2 max, whereas in endurance-trained athletes it typically occurs at around 75-90% of VO2 max.” When the word “turn-point” is said here, it is being identified as the point when running speed increases slightly but an athlete’s blood lactate readings jump immensely.

How can you increase your lactate threshold? Several different sources feel that a trusted way to increase a runner’s lactate threshold is to run “threshold runs” or runs right next to the point where lactate begins to accumulate in high amounts. If you ever get a chance to read Jack Daniel’s Running Formula, within that book there is a chart which can easily approximate the speed at which training runs should be accomplished, according to the athlete's VO2Max or current running ability. To get the best measurement to determine one’s lactate threshold a set of muscle biopsies or blood pricks would be needed. Due to the difficulty of this, a heart-rate training procedure can be used to replace these. Heart rate increase often is closely correlated with increases in blood lactate within the body. By calibrating a heart rate monitor for each specific athlete, workouts can be reviewed and can help determine an athlete’s threshold. By training at or slightly above one’s threshold level constantly, the body adapts and allows runners to push themselves into higher lactate threshold levels.

Genetics are often pointed to when lactate threshold is the topic. Several studies have shared their findings that increases in slow twitched muscle percentages allow for the highest possible LTs. Alternatively, a study produced by Adèle R. Weston et al. entitled African runners exhibit greater fatigue resistance, lower lactate accumulation, and higher oxidative enzyme activity, the researcher shared information which appears to question previous findings. The results highlighted findings that significantly more active oxidative enzyme activity (citrate synthase, and others) and longer time until fatigue was shown in African runners than in performance-matched Caucasian runners. Ironically the average type 1 muscle ratios were higher in the Caucasian runners who had an average of 67% versus African runners having only 49%. If the results found in this experiment are true, its implications cause one to consider the need of high slow muscle ratio for a distance runner.

Threshold training is important for distance runners. Though I have changed my philosophy of workouts many times since I begun running competitively, I naturally throw in threshold runs weekly because it makes me feel more powerful, more relaxed at “uncomfortable” paces and mentally stronger. I am only more and more convinced that there is a very close correlation between LT and pain management.

This last season of cross country I became curious about strength training in addition to my running. I would perform sessions of 30 minutes twice a week throughout most of the season. I did this mainly after reading the interesting studies about increased performance capability through changes to the neuromuscular adaptations. These exercises were almost entirely anaerobic in nature. I ended up doing very well at the end of the season and while I feel that my key running workouts were what help my body adapt the most, these strength training routines were excellent times where I could focus on pain management. In the weight room I am not sure if I was able to increase the strength of my running muscles in ways to help my body significantly, but I was able to help my brain/body take on high levels of pain. This made even the hardest workouts and races bearable. 

Increase Running Economy

Increase Running Economy

Running economy or running efficiency is crucial for distance runners. Specifically, the longer the race, the more important having good form becomes. I was watching the US Marathon qualifying race in Houston recently and I was amazed at how great the top runners looked even after being almost through the whole 26.2 mile race. When your looking visually at a runner to predict if they have good form, there are a lot of individual areas of interest a person can look at. Some of the things that stood out the most from this recent race was most importantly the frequency always stayed high and secondly, it appeared that every part of the runner’s bodies were toned in such a way that no extra fat or muscle seemed to hinder the body’s running motion.

There are different ways to improve running economy. Depending on what your running background consists of, simply running every day may significantly help your running economy. If you are a trained runner you may need to seek to enhance your running economy through other methods. A person may have a very difficult time increasing their VO2Max once they are already in competitive running shape such as the end of a track season, but don’t let this discourage you. You can still get faster, much faster, by increasing your running efficiency and elevating your lactate threshold.

In a scientific review of the literature a meta-analysis produced in 2007 by Adrian W. Midgley et al. entitled, “Training to Enhance the Physiological Determinants of Long-Distance Running Performance” identified how there are three pivotal factors to look at in predicting a runner’s ability. They are, in no particular order; high aerobic capacity (high VO2Max), running efficiency, and an elevated lactate threshold level. Each of these is directly correlated with a runner’s performance. If these determinants are weak there will be a slow performance, while on the other hand, if they are optimized, performance is optimized. In this section we are talking about running efficiency. If we can improve running economy, we can run faster—period.

In college, I’ve been seeking to improve running economy the most whenever the races got the most important. Typically the races that matter most are usually always at the end of a season. Because of this, I like to set up my own training in a periodized and progressive way. One thing that I have observed since high school is a link between running economy and becoming injured. I have had friends that I believed had exceptional running form namely Kyle Ehrke, James Padilla and Nick Jones. All three of these runners are terrific runners yet all have had problems with their injuries at an almost chronic level. Perhaps if strengthening programs were used to better train some of the weaker stabilizing muscles then they would have been able to run more races in the past, but perhaps not. What I am suggesting, is that some people are more prone to injuries than others and that I suggest that those people are often those with naturally good running form.

Anyways, the reason I bring this up is because I feel that I can relate with this concept. Often the times that I feel that I am running the most economical possible, I feel I am on a fine line of becoming injured. Going into may final races at MCC I had a nagging issue with plantar fasciitis mixed with very stiff Achilles tendons with a bit of IT Band Syndrome occasion but I was able to produce very significant PRs. As a runner devoted as I was back then, I didn’t care about hurting before or after. All that mattered to me was staying healthy enough to go to all the workouts and last for the races. Often it would take an hour or more or so a day of stretching, homemade strength training routines and/or yoga along with sleep after training to maintain what I considered a healthy runner’s body for myself.

Due to the fact that I do not care much about early parts of seasonal training along with the fear of getting injured, I do not spend as much time focusing on improving running economy during the beginning part of a training program. I make sure that I do not get excessively fat or muscularly bulky so that I do not hinder my stride, through constant training runs. This is actual a major issue for myself. When I stop running for some time it appears that my muscles get significantly bigger, so I have to stay active and diligent in running even in the off season. When comparing Kenyan runners with other groups of runners from all over the world, Saltin et al. 1995 discovered that Kenyans elite distance runners had a lower BMI then other runners. No groups of people are better distance runners than the East Africans. It doesn’t matter if its muscle or fat, if you weigh too much you most likely will not be competing for world records. As an example when I was at MCC running the steeplechase I was 5’7” weighing in at 150 lbs. At the time one of the people I raced against was Henry Lelei from Kapsabet, Kenya who was I would estimate 6 foot flat weighing a little less than 140 lbs. Looking at our BMI’s I was 23.5 (kg/m^2) while Henry was around 18.7, which related in similar fashion to our times mine being 9:47 (8^th at NJCAA nationals) his being 8:56 at region and he was 1^st for NJCAA nationals. Since then I have ran faster times running at a comfortible 143 ish in season. Which may not seem like that much of a difference but next time you go for a run hold on to a 7 pound weight for 6 miles, its amazing how much it starts affecting you especially when you are already fatigued.

I do not mean to mislead my readers. Having improved running form does not always correlate with increases in injury, in fact, a study was produced by Williams, K.R. in 2007 which states that having improved running economy reduces the risk of injury. What I believe is the best situation for a runner is to always strive to improve running economy, but to really focus on it the most towards the end of a given training program. I’m sure others would argue against me suggesting that an athlete following that plan would learn bad habits (bad form) due to sensitivity of the nervous system towards the beginning of learning a skill. So perhaps for beginning runners, running form training should not be delayed. Advice for these runners is to focus on their own personal needs. If there are strengths in some areas, that runner's time should be spent on their weaknesses. If their weakness is running efficiency then work should be done to improve that determinant. One very important thing to remember is that often simple, consistent training will lead to better form, higher aerobic capacities and elevated lactate thresholds. I remember my assistant coach Dallin Alldridge telling me in high school, “consistency is the key”. That is a statement which I definitely agree with. If there are two fairly new runners at the beginning of the year and one runs 5 miles a week and another runs 50 miles a week I guarantee that 99 times out of 100 the 50 miler/week will have better running economy.

To illustrate how powerful enhanced running economy means to performance I give the example of Steve Prefontaine and Frank Shorter. These two runners were friends and raced against each other occasionally. Steve and Frank were both measured for their VO2Max. Steve had 84.4 a large value which would makes sense due to the countless records he smashed before his unfortunate death. Frank, a gold medalist in the 1976 Olympics maraton, had a modest 71.3. When comparing values, PRE had a 16% higher VO2Max than Frank Shorter. Yet when looking at their times in the 10k Steve was only 1.5 seconds faster than Frank’s 27:45. When looking at pictures of Frank he looks like the skinniest runner you have ever seen with a reported 3 percent body fat level. Though Frank’s heart can’t pump as hard or as much as PRE’s, because of Frank’s efficiency he didn’t need it to. Conley and Krahenbuhl 1980 found that running economy is so important to runners that after testing 12 runners, all the runners who had the best running efficiency had the best times. After these findings they stated, “a high VO2max (anything above 67ml/kg/hr) was “membership” to this elite group- Once in this group, Running Economy (Not VO2max) was the leading factor controlling success at the 10k race.”

Now that we understand that running economy is important, how do we train to enhance it?

-Train consistently with good amount of miles.

-Train at your lactate threshold level.

-Implement explosive strength training (gradually at first).

-Perform plyometric training drills.

-Choose a natural frequency and stride length for your body (rate should be near 180 steps per minute- watch any professional and it will be around 180-200).

-Hill Training which provides power especially for weak runners.

-Train at your race pace.

           To conclude, running economy is a fundamental concept of energy cost. If you are able to produce the most amount of force on the ground possible, maintain a high rate of turnover, have a powerful stride length while keeping your body’s system from fatiguing excessively through masterful economy, PRs await you my friends.

Build High Aerobic Capacity

Build High Aerobic Capacity

            One of the first things to realize as an educated endurance athlete is that there are abilities that can make your performance increase dramatically without too much influence on your appearance. There may be two athletes that are the same height, weight, lean body mass and even muscular coordination through seasons of training, but when asked to run a 5k on a track one athlete leaves the other in the dust. This example may lead a person to contemplate the question, “what is making one runner faster than the other”? Often an answer is given with one word, GENETICS. Genetics is the fundamental fabric of our lives supplying beneficial or non beneficial characteristics for our bodies. If you were to ask professor Joke Phd here at BYUH, he would tell you that “if you want to be one of the best endurance athletes, you need to have the right type of characteristics of a distance runner”.

            Though the two runners from the example above may both have the same percentage of lean body mass or muscle mass, they may have different types of muscle fibers in their limbs. Having different types of muscles may play in important key in performance. We see this often in Track & Field. The top class sprinters and top class endurance runners differ in the amount of slow twitched muscle fibers. This example helps demonstrate the difficulty in visually trying to choose distance runners out of a group of athletes.

            One of the easiest ways to identify good endurance athletes out of a group of people would be is to perform a VO2Max test on those individuals. The results of this test will tell you how much oxygen can be pumped into an athlete’s body to help perform work. There are many factors that create an athlete’s VO2Max including cardiac output (stroke volume x heart rate), lung diffusion, muscle metabolism and blood’s carrying capacity for oxygen. When seeking to determine which factors are the most important, Midgley et al 2006 concluded that, “It appears that changes in Stroke Volume (most importantly) and widening the Maximal Arterial-Mixed Venous Oxygen Difference of a runner are the most important factors in Increasing one’s Vo2 Max.”

            In my physiology class this last semester, I was surprised to see that even EXS (exercise and sport science) majors here at BYUH had confusion understanding what stroke volume was. Stroke volume is the amount of blood that a person’s heart pushes with every contraction. One may notice that top class endurance athletes have very few beats (perhaps 30-50 bpm) compared to the average individual (55-70 bpm) when at rest. The top class athletes are able to have much fewer beats per minute because with every single pumping of the heart, significantly higher amounts of blood are being pushed through the body. Having a physically larger heart is helpful in optimizing your performance as a distance runner. If a certain person has a stroke volume of 120 ml per beat and has a heart rate of 170 beats per minute then their total amount of blood being transported throughout their body would be 20,400 ml or 20.4 liters of blood in one minute. If another person with a weaker heart was only able to pump 70 ml per beat with the same heart rate of 170, this person would only be able to move 11,900 ml or 11.9 liters of blood through their body. That is 20.4 L compared to 11.9 L which is 1.7 times more blood per minute.

            To review what we have discussed so far, superior endurance performance is not always visually identifiable from the naked eye. One way to see if an athlete would be a good distance runner would be to check the strength of their heart. To check the strength of their heart, a VO2Max test can be performed. A strong heart is able to pump large amounts of blood with every beat.  This is how far we have got. Next it is important to realize why pumping large amounts of blood helps athletic performance.

            Within our blood we have red blood cells that contain hemoglobin which attaches to oxygen while in our lunges in what is known as the pulmonary capillary network. From here the continuous pumping of the heart circulates the blood now carrying oxygen. Oxygen is required for our bodies to accomplish aerobic work. Because aerobic work produces no significant waste products, high levels of activity can be maintained for long periods of time without our bodies getting tired. The only waste product produced, in fact, is CO2 carbon dioxide, which we breathe out during our exercise. Due to its efficiency, it has been estimated that around 90 percent of the energy requirements are met through aerobic (oxidative phosphorylation) methods during a 10k race for elite runners.

            This section is dedicated to teaching individuals on how to increase one’s aerobic capacity or VO2Max. If I were trying to increase my own VO2Max, what would I do? Well, I would remember Midgley et al 2006’s quote from earlier which states that the most important method of increasing one’s VO2Max is to increase one’s stroke volume…  So stroke volume appears to be the largest factor in determining one’s VO2Max. How can I increase my stroke volume? An interesting study was produced in 2007 by Helgerud and his associates entitled, Aerobic Power Training from the journal of Medicine and Science in Sports and Exercise. It was discovered that when different types of workouts were compared, high intensity intervals were the most effective way of increasing both stroke volume and VO2Max. These findings were supported with previous findings found by Laursen & Jenkins (2002) which stated, “It seems that, for athletes who are already trained, improvements in endurance performance can be achieved only through high-intensity interval training (HIT).”

            When researching different aspects of endurance training I often found many different interesting studies that had been done. If a person ever gets a chance to read Lore of Running by Timothy Noakes it is easy to become amazed at how many studies have been documented in relation to one seeking to improve their endurance performance. In my previous versions I had added sections entitled “final thoughts” on the different discussion topics. Some of the final thoughts that are interesting regarding the discussion of VO2Max are some of the following:

·         Elite Runners often do not change their VO2Max very much in later years of training.

·         After about 2-3 weeks of no training one’s VO2Max starts dropping significantly.

·         In general, if an athlete is not either increasing duration or intensity in a training program their VO2Max will plateau.

Estimates of one’s VO2Max are JUST ESTIMATES, in order to calculate one’s actual VO2Max one must be measured using lab equipment that monitor’s the actual amount of oxygen. So many times I hear of second-rate studies suggesting a change in VO2Max of participants when no measurements of Oxygen were ever even considered. Increased performances in distance running does not guarantee any change in one’s VO2Max, it is possible that a person got faster though other methods.

VO2Max is measured by ml/kg/min positioning the average male adult near 45, female near 38 respectively. Endurance athletes are higher generally placing world class men at around 80 or higher and women around 70 or higher. I have been measured at 70 ml/kg/min a couple years ago when I was running around 26:15ish for 8k. One thing that is important to understand about VO2Max is that depending on how a person is being tested, one’s VO2Max value will change. If I am a runner and am asked to be tested on a stationary bike rather than a treadmill, my values may be a couple units lower than if I was to do the test running.

These are my thoughts on instructing a person on optimizing their aerobic capacity. I hope some of the things I have shared helped you.

Table of Contents

Introduction

           One of the fundamental reasons for the exploration of these principles was in consequence of my high school running experience. I was always perplexed how I could train hard and compete well all year and never a finish a season strong. I would watch runners I had beat all year pass me when the races really mattered. I wanted to train the absolute best way possible and I felt there were places for improvement.

            When I was signing up for some classes as a student at Mesa Community College, I remembered that coach Condon often spoke very highly of a certain instructor by name of Jeff Messer. I decided to sign up Introduction to Exercise Science with Dr. Messer. I have never met a human being so passionate about his calling as an instructor. Since that class (Intro to Exercise Science), I have taken 2 more classes namely EXS275, Methods of “Optimizing” Physical performance and EXS230 Intro to Research Methods. In addition to being a wonderful teacher Jeff coaches many runners who perform at very high levels.

            Each semester as part of his classes that I have been a part of, Jeff has asked me and each of his students to present a formal presentation regarding scientific based principles for him and other classmates. Generally the topics are broad and creativity was invited. This book is literally a culmination of the ideas and personal learning I started by taking Jeff’s EXS classes. 

            After receiving my associates degree from Mesa Community College, I left to pursue further education and athletics in Laie, Hawaii. There I attended Brigham Young University Hawaii meeting other great professors who only strengthened my knowledge and desire to more fully optimize my own endurance performance. I was able to perform very well for the  Seasiders and was honored to be a team captain my senior year. I was able to enter the 25 club, which was a goal of mine over 6 years, running a PR 25:36 in the 8k on a hilly cross country course (6^th fastest in the school’s history). Lastly, I was able to peak very well with a 32:47 10k cross country time to close out the season (4^th fastest in school’s history)

            While here in Hawaii, I was able to meet my wife Kelsey who was signed the previous year for BYUH for her running ability.  Through this new change in my life, opportunities have been presented. I have been able to coach Del Sur Middle’s distance Currently I am currently continuing to learn more about exercise science especially in the realm of physical therapy. I am busy these days studying school and performing an internship for North Shore Physical Therapy & Sports Medicine in Kahuku, Hawaii, which will help me in my efforts to eventually get my own D.P.T. certificate

            This book was originally designed solely as a collection of data-based objective oriented research studies to not only teach myself correct principles, but to remove as much bias as possible. After collecting over 450 resources composing the third edition of this book, I was inspired to continue to build on this compilation with personal experience-based findings. This latest edition will include my personal experiences which I hope will further illustrate the principles discussed. Some of the questions that I learned over the past years or so which I feel have greatly enhanced my knowledge of distance running include the following:

What is Vo2 Max?

What is Running Economy?

What is a Lactate Threshold?

Are recovery days important?

What is Periodization?

Why is nutrition important for runners?

What nutrition is good/bad?

What is the idea of diminishing returns?

Are there in-race strategies?

What type of stretches should I do?

What is Glycogen?

What are energy phases?

What is Lactic Acid?

Why would anyone consider a vegetarian diet?

How can someone reduce the risks of heart disease?

Why do I occasionally have GI distress?

How can peak when races matter most?

How are elite level runners training?