Strength vs. Endurance Training: How do you mix oil and water?

There is a lot of discussion in the strength and conditioning circles about how much time “endurance” athletes should spend strength training and vice versa.  Training for one outcome in most cases negatively impacts the other.  At Titan we train a number of athletes both endurance and non endurance strength and power athletes.  We are constantly working on better ways to take parts of one type of training to enhance the other.  It is even more important when you have a limited amount of training time with an athlete.   In the strength and conditioning circles there tends to be a perception that you can only do one or the other.   Take a look at premier league soccer players today versus 10 years ago and you see how much bigger they have become and  yet they can still run for a 90 minute game.  Some of them look like rugby players, yet soccer is considered one of the most aerobically taxing of sports.  Today’s sportsmen, both endurance and non-endurance, have to be both strong and be able to produce power at extremely high levels for longer and longer periods of time.

So what is concurrent training and how do you most effectively utilize what we have learned in the training of both types of athletes? Training time is more and more valuable so concurrent training is something that needs to be considered.   In previous blog entries I have discussed the importance of having a primary objective for each workout.  This is even of greater importance if you are concurrently training an athlete.

Many strength coaches believe that any amounts of endurance training will diminish the ability to produce strength and power.  On the face of this it does not make that much sense.  If this was the case then why does it take so long to make gains if all you do is strength and power training?   You are not going to change fast twitch muscle fiber to slow twitch and vice versa with small amounts of training in the other area.  However, with the right strategy a non-endurance athlete can improve the ability to perform short term high intensity intervals and larger amounts of high strength and power outputs by adding some longer term endurance training to the strategy.  This doesn’t mean an offensive lineman is going to train for a marathon.  It just means that if the ability to recover between intervals is improved then greater output and overloads can be obtained in the intervals performed.   On the other side of the coin an endurance athlete can improve average power output on longer term efforts by adding short term strength and power training.  This also will result in the each type of athlete being able to obtain bigger overloads in the energy system most important to the sport.  I call this “opening the window” to other areas of fitness that are positively correlated and improve and support training.  I have cyclists that will go months without any short term intensity because of some conventional training methods that dictate this in the winter.  They seem perfectly fine with this idea.  However, when I ask them what they think would happen to their fitness for racing a bicycle if they did nothing but 100 meter sprints for 4 months, they usually respond with a gasp and think they would lose all of their fitness.  Then I ask them what they think happens to their ability to go hard if they don’t go hard for 4 months straight!  So, you must open the window to all the necessary energy systems necessary for your sport.  At some times the windows are open wider and other times not so much.  I have spent a lot of time looking at periodization and will talk more about this in a later post.  I am looking at this principal from a completely different perspective and how it may be able to improve performance by turning it on its head.  The point is that you need to regularly question tried and true training conventions.

Coming back to concurrent training, there are some definitions necessary to better understand how strength and endurance improvements come about, and the primary enzymes that impact these improvements.

AMPK- Activated protein kinase.  Without going into all the physiology involved, understand that this enzyme is activated when large amounts of ATP are needed for exercise that is long in nature.  ATP is necessary to fuel this type of exercise.  AMPK increases you ability to uptake substrates of sugar and fat to fuel the exercise.  You also see the role of epigenetics involved in giving your muscles more endurance as a result of this enzyme being regularly present.  Greater capillary density and mitochondria are evidenced when longer amounts of endurance training take pace with the activation and presence of AMPK.  Higher intensity intervals increase the levels of AMPK.   Many trainers think that high intensity intervals provide a halo effect that bumps the metabolism and results in weight loss.  However, AMPK increases fat metabolism and sugar uptake as a fuel source for supporting this type of exercise and will make changes in the gene expression.  (Exercise &AMPK Activation, Derek Beast, Charlebois Feb 2005)

mTorc1-mammalian ‘target of rapamycin complex 1   

mTorc1 activity is required for muscle growth and increased strength.  It is most active during resistance training.  This enzyme regulates protein synthesis.  As it increases, there is an increase in protein synthesis and subsequently muscles get stronger and bigger.  So if you want to increase strength you need to increase the presence of this enzyme.    Amino acid supplementation activates this enzyme and that is why adding this to a post workout recovery drink and prior to resistance training can be helpful in developing strength.  Your body has a way of seeking homeostasis so you can’t just keep adding amino acids and expect strength.  So adding amino acids before and after heavy resistance exercise is helpful in maximizing strength gains.  If you do not time the amino acids effective you body will reduce the activation of mTorc1 to seek equilibrium.  You want mTorc1 as high as possible for as long as possible for maximum effect.   (Sports and Exercise Nutrition pg 126. Susan Lanham 2011)

So how should you think about both of these enzymes and the interaction?  The problem lies in the fact that one enzyme turns off the other.  This is why strength coaches are so opposed to doing both.  However, you can strategically incorporate these together effectively by following a few rules.  What we have to do is reduce the impact of one enzyme on the other.  AMPK is increased with high intensity intervals.  You can increase this further by training in a low glycogen environment.   If you are going to follow your endurance training with a strength session add some carbohydrates to your diet after the workout.  Higher glycogen will reduce AMPK after the workout to help negate the impact on mTorc1.  Make sure that the strength portion is low on volume and high on intensity.  This is also tactically easier to accomplish for most athletes as intervals can be mentally and physically very taxing.  Higher glycogen will reduce the impact of AMPK on mTorc1.  You can also add a pre resistance workout protein drink to activate mTorc1.

In a previous post I discussed power times an X factor when analyzing a sport and subsequent training requirements.   The X factor is the level of power needed how many times (X) to be most competitive in a sport.   When looking at training both strength and endurance simultaneously you need to look at the X factor of the sport and the needs of the athletes to take the best advantage of these enzymes and the impact on endurance and strength.   Understand there may be a time when your training is highly focused and you  will not perform any concurrent training, however if used strategically it can enhance your ability to perform the primary training objective for your sport and better utilize limited available training time.

So keep an open mind and no matter what the sport identify ways of better supporting the primary training objective within your sport.

Train smart, have fun, and you will prevail!

Jacques DeVore, CSCS

President Titan Sports Performance and Sirens Fitness

www.titansb.com  www.sirensfitness.wordpress.com

How Your Brain May Limit Your Physical Output and What It Means to the Order of Exercises.

I was recently reading some research on VO2 max and what limits this max.  For those of you who may not be familiar with VO2 max, it is the absolute limit on how much oxygen you can deliver to your muscles during exercise.  A Tour de France racer may have a VO2 max in the 80s.  The average man could be half or less of that.  It is the size of the engine that you have developed to deliver the oxygen needed for aerobic endurance.  The other side of the coin is the utilization of the oxygen once it is delivered.  That is another story that I will talk about in a later blog.  A large amount of time is spent on how to increase this VO2 maximum. The research I read discussed the concept that we never really reach our maximum because our brain, which is always trying to keep us alive, will not allow this to occur as a defense mechanism (Tim Noakes, “Central Governor Theory”).

What was as interesting to me was the discussion of testing methods for VO2max.   Most of the tests are conducted with a progressive exertion until you reach failure.  What they found was that if they reversed the testing protocol to reduce the effort the V02 that was produced was 4.4% higher. This increase is significant when looking at the difference between winning and losing.

The science showed that the brain does have a role in the maximum output.  The speculation was that emotional stress affected the output.  If you have ever taken one of these test they are very painful and you never look forward to having to take them.

What I found interesting was the possible application to the training and the impact on the structure of training high intensity exercises. With that, i thought about a descending order or an ascending order of the intensity.  I have found this anecdotally to be true. When I am conducting interval sessions and the athlete knows the hardest output is on the front end the maximum output is usually better than when I reverse the order.  Remember there are a time and a place for reversing the order and I will use this when appropriate.  Competitive sport is not always in a linear output.

The real lesson to be learned is that you want to pay attention to the effects of the brain on output.  When you are trying to get max outputs and overloads in your training you may want to start with the highest intensity first and then know that it will get easier as the session continues.   When creating exercise order do not underestimate the brain’s role in getting overloads in your training.

 

Train smart, have fun, and you will prevail!

 

Jacques DeVore, CSCS

President Titan Sports Performance and Sirens Fitness

www.titansb.com  www.sirensfitness.wordpress.com

 

 

How Bad Do You Really Want It?

How Bad Do You Really Want It?

The other day I saw a YouTube video about motivation, which particularly asked the question about how bad you want it and what are you willing to do to accomplish your goals, aspirations, dreams, success.  I have seen it in the past and you may have also seen it:

http://www.youtube.com/watch?v=lsSC2vx7zFQ&feature=related

It is worth a look, definitely made me want to go train. This video shows an athlete intensely training, which was portrayed nicely with great narration and music. I often here lots of clichés about motivation and sacrifice. Reality shows are produced so that  the sacrifice necessary to truly realize something can become melodramatic  because it makes good TV.  There is no longer an Olympic Athlete who doesn’t have some story to make the struggle greater, as if the training and sacrifice is not enough.  So I thought I would write about things that I have seen through the eyes of a strength coach that may help you to accomplish your fitness goals.

I regularly see a large number of people who speak from two sides of their mouth.  On one side they talk about their desire to change and how motivated they are to make change; out of the other side of their mouth they have a regular list of excuses as to why they never accomplish these changes and all the reasons (excuses) as to why they can’t do what it takes to be successful. In the video, a lesson is taught about success by holding a young man’s head underwater until he starts to fight to breathe. Of course this is an extreme example.  However, it demonstrates that if you want something bad you will fight for it.    This example really just states that you have to be willing to fight hard if you really want to overcome the obstacles that are in the way of success. If you are unwilling to make that type of effort you will never accomplish something truly great.

 Here are some real life tips:

 

•  First, there must be a sense of urgency!  Most people realize that good health and fitness is necessary, but they do not make it urgent.  It is your health!!  If you are an athlete you MUST realize you have very little time.  It is urgent!  Don’t make the mistake of “I will do it after the holidays,” etc.  The holidays just keep coming.   I will do it next season.  THERE IS NO TIME BUT NOW!  Look at what you value in life and how much health and fitness impacts those experiences.  NOW IS THE TIME! NOW IS THE TIME! NOW IS THE TIME!

 

• Do not diminish or let someone else diminish the value of your goals.  People who cannot make the sacrifice to accomplish a given goal often times diminish the value of the goal so that failure is not a real loss. These same people will try to sabotage your pursuit of the goal so that they are in good company and do not feel as bad about their own failure.

 

• You climb a mountain one step at a time.  Work backwards and layout a simple framework that has dates and each step.  KEEP IT SIMPLE BUT HAVE DATES!  Create small victories and focus on the steps not the top of the mountain.  It will be there before you realize it.  Celebrate the small victories.

 

• Now the hard part. How do you maintain the motivation?  People ask me all the time about how I fit my training into my crazy life.   ELEVATE THE GOAL AND REFRAME THE ISSUE!  You must elevate the importance of the goal in your life.  This goes back to the video.  The example in the video shows that you will have lots of motivation to get your head above water when you run out of air and are drowning.  You will fight hard for that breath because it is urgent and necessary.  Health and fitness do not come without sacrifice.  Elevate the value of feeling good about yourself and your health to such a level that you will be able to maintain your motivation to get out and train and eat well.  Revisit these reasons regularly and reinforce the value of eating and training and how it impacts your life.  Everyone always says “at least you have your health”.  So put some value on what health means to your life.

 

• The Holidays are here and there are a million excuses as to how it is so hard to eat well, not drink too much, workout etc.  Of course the holidays will make it more difficult!  But elevate your goals and you will get through them. Fighting for a breath of air is hard, fitting in a quick workout, or passing on a desert is not asking for much.

 

Train smart, have fun, and you will prevail!

Jacques DeVore, CSCS

President Titan Sports Performance and Sirens Fitness

www.titansb.com  www.sirensfitness.wordpress.com

Have a great holiday!

 

New Sirens Workout Room

Sustainability: Some Thoughts on How to Sustain a High Level of Training and Performance

Wikipedia defines sustainability as the capacity to endure.  For humans, sustainability is the long-term maintenance of well being.  How do you more effectively accomplish sustainability in fitness?

When training for peak performance sustainability is of great importance to reaching the highest level of performance and health.  Whether you are an Olympic Sprinter or just the average person, we all encounter similar obstacles when it comes to sustainability.  I recently consulted a competitive 100 meter sprinter about his training.  He indicated that he was losing his motivation to train and was concerned about the impact on 2012 and the Olympics.  He was recovering from injury and the clock was ticking and with each passing day his level of stress was increasing.  This is common with many competitive athletes.  Many are more driven by the fear of failure.  You ask any successful athlete and most hate to lose.

The advice I gave him applies just as well to someone who is just trying to improve fitness and overall health.  I suggested to him that he not allow himself to look so far ahead.  I could see in our conversation he was already looking ahead over a year away as if he was in the blocks racing tomorrow.  The anxiety was palpable.  I suggested that he focus on what he could control in his training right now.  Focus on getting the most out of his next training session measuring the outcome of the session.  Did he get a great workout?  Did he focus on the pure joy of being able to run fast?  I asked him to focus on some goals that would be attainable in the training.  We discussed sustainability and how difficult it can be, even for the most motivated of athletes to sustain the discipline to train effectively.

Most people are unable to sustain good diet and exercise because their perception of the effort creates an obstacle that is insurmountable.  This perception is what creates an environment that will lead to failure.  It also can allow the individual easily find a reason to fail.

So if you want to sustain a healthy exercise and eating plan, do not create an environment that raises anxiety.  Start with little steps and soon you are able to handle more.  If you start attempting Everest on your first climb you may never climb again.  In exercise, I call it “post traumatic exercise” syndrome.  You expose yourself to an exercise and eating change that is so stressful no human will ever want to continue forward.

Focus on the outcome first and the goals second.  Be in awe of what your body can do at any level and then slowly challenge yourself until the athlete or champion emerges.

Train smart, have fun, and you will prevail!

Jacques DeVore, CSCS

President Titan Sports Performance and Sirens Fitness

www.titansb.com  www.sirensfitness.wordpress.com

Exercise Progression: How Much, How Fast?

Progression is one of the most important concepts in training.  I personally think it is even of greater importance when athletes begin to reach an elite level of fitness.  There is a lot of study on periodization and the management of progression on a macro and micro level.  The majority of lower level athletes will follow a linear progression.  This is a simple straight line increase in intensity and volume of exercise based on maturity and sport.   It is actually not a bad place to start because of the simplicity.  The only risk can be that increases are too great and the risk of injury can become higher. At Titan www.titansb.comwe prefer an undulation of volume and intensity with constant monitoring of recovery.  We utilize as many methods to speed recovery as possible to
increase the ability to overload the athlete again and increase the progression where possible.

The biggest problem with much of the training of an elite athlete is the lack of regular progression.   Progressions become smaller and smaller as athletes get closer to their genetic potential. However, the impact of gains in performance become bigger and bigger on the difference between winning and losing.  Unfortunately, the systems that
are employed to monitor these progressions are flawed.  In many cases where progression is most important less time is spent on fine tuning this strategy. Poor planning and monitoring of performance loses precious time and results in lesser gains and breakthroughs for the elite athletes.

Let’s take a look at this concept of time for a moment and you can see the impact of the loss of time on an athlete’s career.  I have said in the past that what a strength and conditioning coach really charges for is time.  If an athlete in the early part of their career could possess the fitness that they obtain from years of training how much better would they be early in their career?  This is not possible, however a good strength coach shortens the time that it is required  to  reach high levels of fitness by understanding how to progress the athlete,  what areas of training will elicit the greatest impact on athletic performance, and understanding the science, past and present, that will produce the highest level of athletic performance for an athlete.  This is all coupled with the underlying premise of not increasing the risk or causing injury.

Let’s look at the math.  An athlete trains from the age of 10-20 and builds an athletic base and matures during this first ten years.  This time is most often spent on building a good athletic base.  Unfortunately in today’s environment of specialization many athletes become one dimensional and will start to develop injuries or potential for injury if they do not balance out their training and address any weakness that may have developed as a result of the specialization.  The next 10 years of training are the most important.  The athlete’s athletic gains are made with greater difficulty because they are now closer to their genetic potential.  The impact of good progression becomes critical at this time because time needed for big improvement is greater and there is a diminishing ability to produce greater gains as the athlete becomes older.  So there is a greater need for performance and a clock that is always running as the athlete ages.  This is a difficult balancing act.

At Titan understand the impact of wasted training time is greater in these critical years.  If a program does not address progression and address optimum progression rates then the athlete will never become as good as they could have been.  In addition the mental frustration begins to take its toll.  Athletes want to see gains.  It is the nature of sport.

There are many studies on progression.  However this concept is very dynamic and individual.  All the ingredients of rest and recovery, fuel, stress etc become of much greater importance and must be addressed to optimize progression.  It is very easy to not address this on a long term basis and the athlete wastes the best years for huge gains.  Lance Armstrong lived like a monk in order to accomplish this.  Food, training, rest, recovery, are managed like a battle campaign.  Wining a war is all about preparation.

So pay attention to progression and make sure you are making the changes that result in the fastest, safest performance gains.  At Titan we spend a great amount of time monitoring and developing progressions that work most effectively for a particular athlete.  If you want great performance gains you   should spend the time to look at your
progressions and make sure this important aspect of your training is being addressed thoroughly and effectively.

Train smart, have fun, and you will prevail!

Jacques DeVore, CSCS

President Titan Sports Performance

www.titansb.com

Low Glycogen Training

Below is a great article on Low Glycogen Training from Peak Performance. This is a must read for cardio athletes and discuss the most recent research on this concept.  Once again the concept of epigentics and exercise comes into play.

Sports nutrition: the latest research into low glycogen training

Could training when muscle carbohydrate stores are low be advantageous to athletes?

Andrew Hamilton looks at the very latest research in this area and how it translates into training recommendations for athletes…

When it was first proposed as a useful nutritional approach to training, the ‘train low, race high’ theory ruffled plenty of feathers because it stood conventional wisdom about carbohydrate feeding on its head. To briefly recap, train low, race high is a theory born out of genetic evolution of the human race, and which suggests that training when muscle carbohydrate stores are low might actually be advantageous for performance.

The reasoning behind the theory goes something like this: our gene selection in the Late Palaeolithic era (when our ancestors roamed the plains as hunter-gatherers) would have been strongly influenced by the need to ensure survival during periods of famine, with certain genes evolving to regulate efficient intake and utilisation of fuel stores – so-called ‘thrifty genes’.

These genes would have enabled our forebears to utilise energy more efficiently, enabling them to forage for food and escape predators even when enduring famine conditions. As hunter-gatherers, without agriculture, they wouldn’t have had access to abundant supplies of ‘carbohydrate-dense’ crops and cereals but in order to survive, physical endurance and the occasional high-intensity burst of energy would still have been needed.

Thrifty genes and exercise

What’s fascinating is that there’s convincing evidence that our genetic makeup has remained essentially unchanged over the past 10,000 years and certainly not changed in the past 40-100 years(1), which almost certainly has profound implications for the 21st century athlete. In recent years, a number of ‘exercise genes’ involved in the adaptation to exercise and training have been identified, and some it seems are also affected by the biochemical environment in the muscle – eg how much muscle glycogen is present or circulating levels of hormones and other signalling molecules released when exercise is performed(2-4).

The obvious question, then, is this: given that these genes have evolved to help us maximise our adaptation to and physical capacity in a low-carbohydrate environment, is the almost universally recommended high-carbohydrate diet for athletes disadvantageous in any way? Or to put it another way, could vigorous activity in a carbohydrate-depleted state (as would have been the norm for our ancestors) possibly produce better training adaptations in the modern athlete? A number of scientists are increasingly confident that (thanks to our thrifty genes), lower levels of muscle glycogen during training might stimulate certain metabolic pathways in the body, resulting in better muscular adaptation to training(5).

Twice daily, alternate day endurance training

One of the earliest and most well respected studies to look into the effects of low-glycogen training compared the training adaptations in muscle produced by performing leg extension exercise either twice a day on alternate days, or once a day on consecutive days(6). Exercising twice daily resulted in muscles performing an identical volume and intensity of training, but doing so in a low glycogen state during the second session of the day.

The striking finding was the very significant gain in both time to exhaustion and total work performed in the twice daily, low-glycogen trained muscles compared to daily trained muscles (see table 1). In addition, the Danish researchers discovered that the low-glycogen trained muscles became better at burning fat for energy and soaking up carbohydrate to store muscle glycogen once carbohydrate feeding was resumed.

Table 1: Maximal power output and time until exhaustion at 90% of maximal power output before and after 10 weeks of training and total work before and after 10 weeks of training

The implications of these findings were startling because they seemed to completely contradict one of the most universally accepted tenets of sports nutrition – that muscle glycogen depletion should be avoided at all costs. In plain English, this research indicated that although low muscle glycogen content is known to blunt performance on the day, when it comes to training adaptation, this might not be a reason to avoid glycogen depletion.

New research, new questions

Very recent human studies have added weight to the notion of train low, race high theory, particularly for producing desirable metabolic effects such as increased fat burning. However, they have also raised important questions because these metabolic effects didn’t seem to translate directly into increased performance (see box 2).

For example, Australian scientists have recently studied the effects of a cycling programme in which selected sessions were performed with low muscle glycogen content on training capacity and subsequent endurance performance(9).

In the three-week study, seven endurance-trained cyclists/triathletes trained once daily, alternating between 100-min steady-state aerobic rides (AT) one day, followed by a high-intensity interval training session (HIT; 8 x 5 minutes at maximum self-selected effort) the next day. Another seven subjects trained twice every second day, first undertaking AT, then 1-2 hours later, the HIT. In this second group of course, the HIT session was completed in a low-glycogen state.

Forty-eight hours before and after the first and last training sessions, all subjects completed a 60-minute steady-state ride followed by a 60-minute performance trial. Muscle samples were taken before and after the steady-state ride and rates of fat and carbohydrate oxidation were measured.
The results showed that, compared to the daily training group, the low-glycogen group experienced favourable metabolic changes, including higher levels of resting muscle glycogen, higher rates of whole body fat oxidation, and higher levels of key enzymes involved in fat oxidation and aerobic energy production. However, unlike the rat study (see box 1)(7), levels of a similar gene transcription activator (PPAR-gamma) remained unchanged. More importantly perhaps, while cycling performance improved by approximately 10% in both groups, there was no additional improvement whatsoever in the twice daily, low-glycogen group.

Meanwhile, similar results were obtained in a study that used running as a training model, carried out by scientists at Liverpool John Moores University earlier this year(10). Although this study did not have subjects following a strict low-glycogen training regime, it did examine the effects of reduced carbohydrate availability, by restricting carbohydrate drink use.

Three groups of recreationally active men performed six weeks of high-intensity intermittent running, four times per week. Groups 1 and 2 consumed a 6.4% glucose or placebosolution respectively. Both groups trained twice a day, two days per week. Drinks were taken immediately before every second training session and at regular intervals throughout exercise. Group 3 meanwhile trained once daily per day, 4 days per week and consumed no beverage throughout training.

Those in group 2 (who were training in a low-glycogen state during their second run) had significantly higher post-training levels of an enzyme called succinate dehydrogenase, a key enzyme in aerobic metabolism and one which indicates that the low-glycogen training had induced a greater level of aerobic adaptation. However, when the researchers looked at performance such as improvements in maximal oxygen uptake and distance covered on the Yo-Yo Intermittent Recovery Test, there were no significant differences between the groups. The researchers concluded that ‘training under conditions of reduced carbohydrate availability provides an enhanced stimulus for inducing oxidative enzyme adaptations of skeletal muscle, but this did not seem to translate into improved performance during high-intensity exercise’.

Low glycogen and strength

Finally, it’s worth reiterating that (as we reported in PP254) there still doesn’t seem to be any evidence that low-glycogen training is beneficial for very high-intensity exercise, such as resistance training. When Australian scientists examined the influence of pre-exercise muscle glycogen content on the activity of several genes involved in the regulation of muscle growth in seven male strength-trained subjects, they found that low muscle glycogen content had variable effects on the activity of these genes involved in glycogen synthesis and importantly, any differences in the activity rates were completely abolished after a single bout of heavy resistance training(11). The scientists concluded that ‘commencing resistance exercise with low muscle glycogen does not enhance the activity of genes implicated in promoting muscle hypertrophy’.

This notion also finds favour with a leading scientist in this field, Dr Keith Baar. He believes that if anything, weight training in a glycogen-depleted state may decrease training adaptations. This is because the transcriptional changes (activating genes) following resistance exercise are no different in a glycogen-depleted state (unlike endurance training) and the greater metabolic stress of training with low glycogen can actually reduce muscle protein synthesis. Therefore, strength training in a glycogen-depleted state should be avoided!

Should you train low and compete high?

If you’re new to the ‘train low, race high’ concept, there’s a lot of information to take in here, so let’s begin by summarising what the current research says about the subject:

1. Training with lower levels of glycogen in the muscles appears to elicit greater endurance adaptations in muscles, such as improved aerobic efficiency and increased capacity to burn fat compared to training with high levels of muscle glycogen;
2. This greater metabolic adaptation almost certainly occurs as a result of enhanced activation of so-called ‘thrifty’ genes;
3. There is no such advantage when strength training; indeed, low-glycogen training may actually be disadvantageous for strength and power athletes;
4. High levels of muscle glycogen are always recommended for maximum performance on any given day (eg during competition); while training with low glycogen stores may enhance long-term adaptation, actual performance during this training will not be enhanced and may well be diminished;
5. It’s still unclear as to the exact performance benefits of low-glycogen training. Although there are undoubtedly favourable metabolic changes after low-glycogen training, the results are rather mixed as to whether these changes translate into performance gains.

The last point is worth reiterating. Although the initial evidence is looking promising, there are a number of questions that we need to answer before we know categorically whether a train low, race high approach offers real performance advantages over conventional training approaches (see box 2).
It’s also worth adding that low-glycogen training carries with it a number of risks and drawbacks (see box 3) and these should be considered carefully before plunging headlong into a train low, race high strategy.

Despite all these caveats, however, a number of exercise physiologists are convinced that some low-glycogen training can yield real benefits for endurance athletes. There’s no doubt that for maximum performance on the day of a competition, you need to start your event with maximum glycogen reserves. However, training is about trying to teach your body to become as efficient as possible at producing energy – your actual performance during training is of lesser importance. So this is the time when it might be worth including some regular low-glycogen workouts. By doing so, you can stimulate your ‘thrifty genes’ to enhance your energy efficiency and production, which when combined at a later date with high-glycogen stores, could help you achieve a PB. Box 4 and table 2 below give some suggestions on how to introduce some low glycogen training into your routine.

Remember, though, to be cautious. If you do decide to experiment with some low-glycogen training, only do so once or twice a week and for limited periods. Be sure, too, to watch very carefully for symptoms of overtraining and fatigue.