Tuesday, August 14, 2012

Ergogenics.. Improving race day performance

By definition it is the tendency to increase work output. Nutrition is a prime example. Consume carbohydrate during prolonged exercise and you can exercise for longer, plain and simple. The mechanism behind the ergogenic effect of carbohydrate ingestion is two fold. Firstly it provides a fuel source for contracting skeletal muscle. However, secondly and of a more complex and less understood nature it staves off the fatigue signals monitored by the brain.

Here we now have two vastly different components that we can target with a little physiological knowhow. i) a peripheral mechanism; being the muscle its-self and the metabolic complexity that is required for continued muscle contraction. ii) the central component; The brain and nervous system that monitors the energy status of the body and ultimately regulates intensity and duration of exercise based upon feedback from the periphery.

Nutritional ergogenic aids can be classified into two main categories. Ones that targets the periphery such as sodium bi-carbonate, nitrates and also fuel substrates such as carbohydrate. These aids all help sustain muscle contraction by either supplying a fuel source, maintaining homeostasis such as pH levels or by assisting biochemical reactions that result in a greater yield of energy production for muscle contraction.

In contrast we have the aids that work on the central component, these being the ever so common stimulants such as caffeine. The central nervous system is what drives the muscles and if we can ‘turn up the dial’ of the output from the brain then the muscle will respond and contract with greater force. Central stimulants weather they be natural or synthetic are simply mimetics that act very similarly to the bodies own hormones. If you stimulate the nervous system the neural drive to the muscles is increased, the cardiovascular system pumps more blood and the body is better equipped to deal with a life threating situation. After all, this ‘flight or fright’ response initially evolved so we could escape danger back in our early years of evolution. Fortunately for athletes enhancing sporting performance works along similar lines. Perhaps adding a little danger to our next race may help crack a few new PB’s?

The power of this up regulation of the central nervous system on human performance is probably best outlined by the old wives’ tale of a mother lifting a car off her child. A super human effort that may be beyond belief but if indeed true may just outline the actual limits of human performance under the right circumstances.

Science has shown that central stimulants can improve performance in a range of events and can be as effective as eliciting a ~1-12% improvement in performance. Notably however is the large inter-individual variation in this performance improvement. Some respond well and others don’t.. so trying your chosen strategy prior to race day is essential. Preferably under controlled conditions so you can monitor any performance improvements.

My latest research project was based on the premise that we can improve performance using ergogenic aids. But more precisely what happens if we combine an ergogenic aid that targets the peripheral mechanisms with one that targets the central component? Theoretically we should get a combined effect. For example consuming dietary nitrate in the form of beetroot juice has now been repeatedly shown to improve time trial performance. It exerts its effects on the muscle itself by increasing blood flow and somehow reducing the oxygen cost of muscle contraction thus, increasing gross efficiency. It has been shown to improve power output during a 10-16km TT performance on average by 3-6%. Then we have good old caffeine that works via a central mechanism. It’s tried and tested and capable of improving performance to a similar degree as beetroot juice. So in theory we could see a 6-12% improvement in cycling performance? Well we tried this and I wont disclose the results just yet, that’s another story.

One more interesting observation that has been tested in the laboratory and proven to work is the use of music to enhance performance. These days its common to see pros warming up listing to what ever it is that gets them pumped up. But what is this pumped up mechanism and how does it work? Once again its simply a central stimulant. The brain in all its complexity sends commands to the muscle. If we can ‘make the brain happy’ by activating reward centres that are integrated with the motor cortex that drives the muscles then we can drive the muscles harder. Ultimately it’s like having a more powerful battery driving the engine.

So where does peak performance lay? Once we have adapted to training and prepared our physiology for optimal performance we must then ensure our race day protocol maximises our physiologies full potential. Optimisation of the performance of the central component through motivation, and the possible use of centrally acting ergogenic aids is step one. Then, giving the muscle every chance of functioning to its full potential by making sure it has adequate fuel for contraction and the biochemical capacity to contract as efficiently as possible while maintaining homeostatic balance.

Now.. get out there, there is a race to be won…

Tuesday, January 31, 2012

Well rounded cyclist or master of the art?

We are quickly approaching the beginning of the road season and hopefully full of inspiration and motivation from all the action of both the Australian National events and the Tour Down Under. The start of the year is often the best time to reflect on the year gone and begin to map out the year to come. I have a few athletes that have given me their goals for the year and we are now beginning to decide the best course of action to achieve these goals as the year progresses.  I try to follow the old premise ‘practice what you preach’ but often find myself training without any specific direction and following old habits. This year I’ve set my first goal to change this and follow a structured program that addresses all the weakness I have in my cycling armour.

Before I go any further I’ll say that I don’t have weak points and any race that I loose is sheer bad luck!!!.... Any good periodised program consists of several key stages which most would be familiar with. Each phase has a specific goal and we incorporate specific sessions/races that will target the physiological/psychological adaptations that we desire.  The basic premise of any program should be this; Step 1: Teach the body to use oxygen, spare carbohydrate and develop endurance to go the distance. Step 2: Teach the muscle to resynthesise energy quickly via the appropriate energy systems, clear waste products, maintain chemical homeostasis and activate all muscle fibres (neural recruitment and patterns). Step 3: Get specific and determine the physiological demands of the races you wish to excel in. Specificity of training is often the most overlooked of all components. Think about.. How long are the efforts required to go with breaks, how many watts do I need to put out in a sprint, can I repeatedly attack and recover to make sure I can go with the important moves in a race?

A well rounded rider may be good at all of these components. More importantly you cannot expect to master all of them in one season. It may be better to stick to one component and focus on it. I have worked with a few guys now that have specific goals and forego the want to be the ‘all-rounder’.  If you want to be good at time trails then hang up the road bike and perform the majority of your training on a TT bike. Stop riding 100+km and focus on going as fast as you can for shorter distances. This would require dedication to interval training and a lot of time focusing on holding power in the most aerodynamically position possible. Once you have maximised your ability to use oxygen (aerobic capacity) you need to work on improving your aerobic threshold. In untrained individuals power at lactate threshold may occur as low as 70% of their peak power and elite athlete with some threshold training may increase this to 80-82.5%. With specific training I have seen individuals increase this to up to around 95% of their peak power but this has taken years of specific threshold training and the ability to hurt like nothing else.

 Alternatively, If you want to be a sprinter then be specific and perform more sprints. This gets a little trickier because you still have to be there and in a good position when the hammer goes down so there are skill components to think about. Sprint training is all about energy turn over. The more energy you can produce the faster you will go. Learning to do this defies the normal physics of endurance training and turns more to all out strength. Ever heard of the mother that can lift a car to save her baby? Under normal circumstances we are unable to activate our entire muscle, we can however learn to do this by maximally loading the muscle and nervous system through either low repetition high load resistance training or through specific all out efforts on the bike. Then comes learning to sustain near maximal power for the entire length of a sprint. Generally speaking we measure anaerobic capacity through a Wingate test which is essentially a 30 second all out sprint. We record time to maximal power, average power and the degree of fatigue throughout the 30 seconds. All of these components will determine the type of sprinter you are.

If you are more inclined to go up hill then training specifically to go up hill is required. Body mass now plays a large role and power to weight ratio expressed as Watts/kg.bodymass is the main predictor of performance.  A good club level climber has a peak power (power at VO2max) of about 6 Watts/kg and a threshold power of around 5.2 W/kg. This may be good enough to hold a few Strava KOM’s but the Pros are pushing sustainable numbers closer to 7 W/kg.BM. Climbing is not all about power to weight it is also about learning to accelerate above threshold and recover again… repeatedly!! I prescribe a lot of out of the saddle climbing for my athletes that  want to improve their climbing skills. This teaches them to recruit different muscles which is a major benefit and can dramatically improve climbing ability.  And of course what goes up must come down so learning to descend quickly and safely is essential.

To achieve goals you need to identify the specific demands of the activity and determine the best techniques to target both the skills needed and the physiological components required. Sometimes it is just the motivation in training to learn to hurt like you would in a race. Training with friends is often a good way to include a little extra motivation to push harder and the best way to improve skills if specific race type scenarios are practiced. So… Get out there and train properly. Map it out, monitor progress ensure adequate recovery and most importantly RACE HARD!! 

Monday, September 19, 2011

Simple Sugars… I think not!!

It could be said that carbohydrates are an endurance athlete’s best friend. Without them we would fatigue and be unable to sustain the 20,000 or so muscle contractions it takes to complete a 4 hour ride.  Physiologically speaking carbohydrates (CHO) are the main fuel source (combined with fat) to supply energy to not only skeletal muscle but also the brain, nervous system and cardiac muscle. Although we usually consume CHO to support muscle contraction and maintain blood glucose there are a few intriguing roles of CHO that many athletes are not aware of. 

Generally speaking the rate limiting step in getting CHO to the muscle is the absorption from the gut into the blood stream. Carbohydrates come in various forms. This includes small and simple CHO such as glucose, fructose and galactose which are all monosaccharide’s.  Bigger more complex CHO take longer to absorb as they are by nature more complex and take longer to breakdown before being absorbed. Under laboratory conditions we know that during intense exercise skeletal muscle can oxidise glucose at a rate much greater than we can absorb it and until recently the maximal rate of exogenous (consumed) CHO oxidation was thought to be ~1g/min.

In a study that has now seen the development of a well known brands ‘C2max’ energy gel formula researchers experimented with using multiple carbohydrate mixtures to see if they could increase the absorption rate when compared to glucose alone. Interestingly when they combined glucose with fructose they found that absorption could be increased by ~50% which then resulted in a significantly greater rate of exogenous CHO oxidation at the muscle (~1.7g/min). This finding was attributed to the possibility that glucose and fructose have different transporters across the gut wall and they coined the term ‘multiple CHO transporters’, which has had much interest over the last few years. For a more in depth insight into all this check out http://www.ncbi.nlm.nih.gov/pubmed/20574242

These same researchers have discovered an even more interesting fact about CHO that could have significant performance benefits for a range of athletes. As already discussed CHO is the primary fuel source for muscle contraction during high intensity exercise however, it appears that CHO may also play a role via centrally mediated mechanisms. By ‘centrally mediated’ I refer to the complex role of the brain and its neural control over skeletal muscle. In a study that looked at the effects of intravenously infusing glucose versus the traditional oral ingestion of glucose on cycling time trial performance an unexpected finding was revealed.  These researchers observed that the distance covered during a 1-hour time trial was significantly greater under the conditions where subjects ingested the glucose orally. They developed the hypothesis that there may be receptors in the mouth that can sense CHO and can positively affect the brain in a way that enhances performance.

Since this first study there have been a multitude of studies completed to further investigate this remarkable role of orally ingesting CHO. It has even been shown that mouth rinsing a CHO solution then spitting it out (without swallowing any) enhances performance. These studies have confirmed that; 1) Certain areas of the brain related to motivation respond to CHO in the mouth, 2) It is the calorific  (energy containing) characteristic of CHO that trigger these receptors because an artificially sweetened solution does not have the same effect and 3) It appears that the duration the solution is rinsed in the mouth is important.

Although much light has been shed on this topic there are still a few small things we are trying to figure out. It is not yet clear if this mouth rinse procedure still has an effect after a meal high in CHO has been consumed. Because most research studies require subjects to come into the laboratory without eating breakfast (fasted) we are not sure if under real life circumstance where an athlete would eat breakfast before an event if the rinse procedure is still effective.  This question is currently being followed up by RMIT researchers in collaboration with the Australian Institute of Sport in hope that they can provide a clear set of guidelines for athletes competing in the 2012 London Olympics.

If you are interested in being a subject for this study you can contact stephen.lane@rmit.edu.au

Wednesday, July 13, 2011

Is speed a mentality?

Ive just recently returned from Europe were I fulfilled a long time dream of seeing the Le Tour in the flesh as opposed to from my couch. The little that I saw made it clearly evident that this race is huge, I mean massive in a way that TV does it no justice at all. The racing itself is only a small portion of what is going on at anyone time. My fetish for all things carbon was completely overloaded and so was the memory card from my camera that nearly went into melt down because I  had a need to capture anything that had 2% body fat or 2 wheels. Esthetically all tour related things are beautiful (except Cadel....sorry Cadel) which of course is the goal of sponsors and teams to make us all lacking in genetic grace want these beautiful, fast, light, sexy pieces of extreme engineering to make up for the performance deficit (I am talking about the equipment not the riders).

As seen in the above photo (bonus points if you can figure out which Schleck brother it actually is) even the riders have to look good. If you are familiar with Zoolander you will recognize the Blue Steel pose. Getting to the point... How much of performance is actually limited by skeletal muscle? Id swear that if I is was asked to fill in for a team during the TTT I would ride faster than I ever have before (until I eventually got dropped). And of course as many of us know getting a state of the art new bike seems to provide this motivational advantage that allows performance enhancement to exceed that of any mechanical advantage.

Ultimately, muscle is controlled by the brain and the brain is so complex that we haven't even scratched the surface of its capabilities.  There is a lot of sports science research that has attempted to determine the mechanisms of this central role of the brain in limiting performance. The simplest  example I can think of is the placebo effect that us scientists go to extremes to control and suppress. If you think you can go faster then you usually do. Performance appears to be a state of mind rather than a physical state especially when you have exhausted your adaptive potential through years of consistent training.

So is it possible to trick the mind into thinking you are an elite athlete? I would like to do a study where I hypnotize my subjects to make them think they are grand tour riders with the ability to put out huge power numbers and then make them perform a performance trial. My hypothesis would be that skeletal muscle would still be a limiting factor, however their would be significant improvements in performance compared to a control trial where the subjects performed it in a normal state.

My conclusion to this post is buy the most expensive fastest bike you can, live a life style that makes you think you are a professional cyclist, make sure you look pro every time you ride (even if it is on the trainer in your lounge room) and most importantly believe you are the fastest!! 

Think fast... GO FASTER.    

Sunday, March 20, 2011

Time Trial Performance - Call for Volunteers

Do you want to improve your Time Trial Performances?
Can you spare 1 morning per week?

Then....Be like the Pro's and get paid to train!!

I am currently recruiting for an upcoming research project entitled; The effects of a carbohydrate mouth rinse on cycling time trial performance commenced in a fed or fasted state. We all know the importance of carbohydrate (CHO) during endurance events. It is the main fuel source at intensities above ~ 60%max and we only have a limited supply. The body stores enough carbohydrate in the liver and muscles to last ~2hrs. Any event lasting longer than this that is performed at a moderate to high intensity requires CHO to be consumed to supplement supply from the liver and muscles.

Surprisingly though, it has been shown that even during high intensity short duration exercise (<60min) when CHO stores are at no risk of running out, consuming CHO can improve performance. This observation has been put to the test using various cycling time trial models. It is believed that there are receptors in the mouth that can sense CHO and relay messages to the brain that help improve neural output to the muscles. This has been proven using medical imaging techniques of the brain. One study measured the brains response to a CHO drink compared to a non-CHO placebo. The CHO drink caused certain parts of the brain that are related to muscle control to become active and we believe it is this link that allows an increase in self selected intensity.

To test this performance enhancing effect a little further my next study requires a group of subjects to perform a series of 1hr cycling TT under several different conditions. Our research is carried out at RMIT University in our Exercise Metabolism Laboratory at Bundoora (Melbourne, AUS). For this I need 12 willing participants to complete one TT per week for 6 weeks. Subjects need to be male, aged ~18-35 and be currently riding >250km/week. Subjects get paid upon completion of the trials, undergo full VO2max testing and receive numerous physiological and cycling performance reports. It past similar trials have been a great experience for myself and the subjects to get some great TT experience and learn some ways to improve performance.
If you think you have one morning per week free and an interest in participating then please contact me at stephen.lane@rmit.edu.au.

Tuesday, February 22, 2011

Research - The best type of Training

Ive always been interested about how things work. Ive often destroyed a perfectly functioning piece of gadgetry trying to determine the mechanisms of  its inner workings. I am now completing a PhD in exercise science trying to unravel the mysteries of the human body, and in particular skeletal muscle. I could talk all day about the mechanisms of how muscle responds to various nutritional and exercise stimuli, and am lucky enough to have the opportunity to document my understanding of such things in my forever expanding thesis. For scientists to understand these mechanisms we devise well controlled, meticulously planned research trials that require volunteers from the general public to perform various tasks within the laboratory so we can collect data and begin to draw conclusions. Who are these volunteers? They are people like you.. and often the hardest part of such research is generating interest and recruiting volunteers. Depending upon the study we will target a specific type of athlete. In general I use well trained cyclists or triathletes as they are familiar with the type of training and testing I use to measure adaptation and performance changes in response to specific interventions. My most recent study required 12 well trained cyclists to complete 4 different trials over 4 weeks to measure the effect of caffeine ingestion on cycling power output under conditions of normal or low muscle glycogen content  (I will make this the topic of an upcoming blog). Apart from being poked, prodded and yelled at to squeeze out every bit of performance possible  being a guinea pig in the research lab is often just a well catered for training session. And yet it has the added bonus of undergoing some physiological testing that if completed outside of a research scenario would possibly cost hundreds of $$$$$. So for a little effort and commitment you could actually be paid to train, yes... there is often financial reimbursement for your time and effort plus you get some very handy physiological feedback. By now I hope I have inspired a little interest in my readers. Although my intentions are to educate, they are also to open some avenues to help me entice a new batch of enthused athletes to volunteer for some up coming research. Next on the books is a study investigating the effects of a glucose mouth rinse on 40km TT performance. Although many athletes are aware of the benefits of carbohydrates during exercise many are unaware of the multiple mechanisms of its actions. Apart from being a substrate for muscle contraction it is also becoming evident that carbohydrates can be sensed by receptors in the mouth that ultimately send signals to the brain that enable us to work harder for longer. Our new study is targeting this action and testing it using four 40km TT performed 1/week over 4 weeks. For this I need 12 cyclists/triathletes to perform each of these sessions. So if you have an interest in research, want to dramatically improve your TT performance and have the luxury of a paid catered training session then here's your chance. For further information about participating send me an email at stephen.lane@rmit.edu.au.

Wednesday, February 16, 2011

The Boundaries of Size and Speed

I do like to day dream. If you slip far enough away anything is possible. I find myself on occasion dreaming of being a genetic endurance freak with the ability to leave my competition gasping for air while I ride away into the distance. Unfortunately, no such luck occurred at my conception and I am left to only dream. Amazingly though such people do exist. Hard work and a little dash of super DNA rounds out the top 10 at most of the grand tours. But yet even beyond these supreme endurance athletes are a small group of actual genetic freaks. The images above, well in particular the rather large whippet dog and the bull of all bulls actually suffer from a disorder where the hormone that regulates muscle mass is not present. This mysterious hormone called Myostatin is produced in skeletal muscle and then circulates around the body to regulate muscle mass. In ordinary individuals no matter how many hours they spend in the gym eventually they reach a level where their muscle mass plateaus. In the case of a genetically modified mouse or a naturally occurring dog there is no Myostatin present to regulate muscle mass so it continues to grow even without any major stimulus. In human cases there are reports of young children with super human strength and a six pack to die for, but yet I am not overly certain of the life span of these fortunate or possibly unfortunate individuals. My day dreams slightly stray from the realms of huge muscles but rather dwell on a VO2max somewhere in the theoretical realms of the spawn of Lance Armstrong (no introduction needed) crossed with Chrissy Wellington (3 x Ironman world champion who goes as fast as most of the guys). So.... what does regulate our ability to uptake and utilize oxygen? Are there individuals who are unknowingly sitting on the couch with the potential to hold 800W for a 40km Time Trial, Possibly? We believe that this potential is partially regulated by the fact that the larger the muscle cross sectional area the further oxygen has to diffuse from the circulation to the center of the muscle and this process is ultimately dictated by the laws of physics. There are of course alternative ways to achieve superhuman performance. Doping is probably the most common and simplest of these forms of performance enhancement. If only they sold EPO at the supermarket, but yet I suppose then everyone would be on it and we would be back at square one again. All in all scientists are still yet to accurately define what exactly limits the boundaries of human adaptation, at the moment I believe the majority of it lies in our minds!!