The Tale of Low Carbohydrate Training

Story time! It’s the best way to talk about the hot topic of fasted/low-carbohydrate training… 

A prelude.  Carbohydrate is needed to perform high-intensity efforts.  However, the body only has so much carbohydrate stored which gets to be a problem because carbohydrates are also used during low-intensity efforts.  As a result, an athlete can use up their carbohydrate stores before the end of a race when carbohydrates are needed the most (i.e. during a sprint stage).  Conserving these carbohydrate stores could therefore theoretically improve performance. 

Now, onto the story… It’s an overcrowded and poorly lit lab space and a researcher is thinking about how to help athletes perform better.  Or maybe it’s an athlete pedaling along during a long sweltering day at the Tour.  Just like we’ll never know how a rainbow is made, the origin of this story is unknown.

So, what’s the big idea?  Train the body to use more fat so that carbohydrates will be conserved for when they’re needed most.  To do this, all you’ve got to do is train while eating a low carbohydrate diet or in a fasted state (to keep it simple, I’ll just say fasted training – in other words, training before breakfast and without eating food).  Training in this way will use up whatever carbohydrate stores you have and then require the body to use fat so that you can keep exercising (even if you’re skinny, you’ve still got ample fat stores).    

Not only does this idea make sense physiologically, evidence supports the idea that fasted training improves the body’s ability to use fat as an energy source.  Research has found fasted training increases the reliance on fat metabolism as well as increases a number of cellular markers associated with fat metabolism1,2,3.

So far, so good.  But here’s where the story takes a turn.  You may have heard that the person with the highest VO2max doesn’t always win the race.  In other words, lab findings don’t always translate to race day performances.  This initial research focused on a variety of markers for fat metabolism but failed to look at actual athletic performance.  When actual performance was measured following fasted training, researchers have found no improvements in performance or even worse performance compared to training with a traditional high-carbohydrate diet2,3,4

As you might imagine, this is when the townsfolk began to think about overthrowing science.  But physiology is complicated. Yes, fasted training improves fat metabolism. However, it has some other unintended consequences.  Maintaining training intensity and even completing planned training sessions is difficult when fasted1,2. The immune system is highly reliant on carbohydrate5, so the ability to fight infection may also decrease with fasted or low carbohydrate training1.

But one of the main pitfalls of fasted training is that the body’s ability to use carbohydrate gets worse6.  When training fasted, the body isn’t using carbohydrate so it can down-regulate the machinery needed for using carbohydrate (if you don’t use it, you lose it).  And remember, carbohydrate metabolism is needed for those race-winning, high-intensity efforts.  As a result, athletic performance suffers.

In an attempt to maintain carbohydrate metabolism machinery, some have suggested athletes train with some sessions fasted and other sessions fed (a “periodized” style of training)2,7,8.  There have been a handful of these studies with somewhat conflicting findings.  For example, a couple of studies found periodized fasted training resulted in greater performance benefits compared to a traditional high carbohydrate diet7,8.  On the other hand, another study found no differences2. Why the difference in findings?  One reason may be that the studies included participants of different ability levels and elite athletes may not respond as well to fasted training.

Now, before you go thinking that this story has a sad ending, there are some cases where fasted training can be beneficial.  Ultra-length endurance athletes who compete at a consistent lower intensity may potentially benefit from fasted training.  Fasted training might also be a way to introduce some novelty to what can otherwise be boring winter base miles (just don’t do it near target races). 

For this story, a lot has been simplified.  If you’re interested in learning more, let us know!  But for now, I’ll end story time.  I hope you enjoyed it while eating (or not eating) a high-carbohydrate snack…  Thanks for reading!

A Tale of Two Files

Dickens, am I right? Well onto the interesting stuff...or rather, stuff, we'll let you decide if it's interesting.

File 1 - Marathon MTB Race at 2000m Elevation

Screen Shot 2017-12-26 at 5.25.42 PM.png

Athlete Metrics

  • 61 kg
  • 180 bpm threshold HR
  • 320w FTP (at race elevation)

Race Load

  • 6:48 race time
  • 4998 kJ
  • 377 TSS
  • 205w average power, 246w normalized power
  • 1.2 variability index
  • 156 bpm average HR (87% of threshold HR)
  • -0.64% Pw:Hr drift

Peak Powers

  • 30 sec - 543w, 83rpm (170% FTP, produced at start)
  • 60 sec - 477w, 82rpm (149% FTP, produced at start)
  • 5 min - 347w, 91rpm (108% FTP, 824 kJ completed prior)
  • 20 min - 280w, 90rpm (88% FTP, 824 kJ completed prior)
  • 60 min - 240w, 92rpm (75% FTP, 3042 kJ completed prior)

File 2 - European Climbing Road Race at Sea Level

Screen Shot 2017-12-26 at 5.36.59 PM.png

Athlete Metrics

  • 60 kg
  • 183 bpm threshold HR
  • 360w FTP (at race elevation)

Race Load

  • 3:47 race time
  • 3112 kJ
  • 283 TSS
  • 229w average power, 286w normalized power
  • 1.25 variability index
  • No HR metrics

Peak Powers

  • 30 sec - 556w, 89rpm (157% FTP, 2612 kJ completed prior)
  • 60 sec - 485w, 89rpm (135% FTP, 2601 kJ completed prior)
  • 5 min - 393w, 88rpm (109% FTP, 2560 kJ completed prior)
  • 20 min - 364w, 86rpm (101% FTP, 2560 kJ completed prior)
  • 60 min - 297w, 88rpm (83% FTP, 2053 kJ completed prior)

The Punch Line

It is what you make of it, huh, so what do you make of it? Well in a lot of ways, I’d say the demands of these races are super similar. On a simple level, physiologically, both races/tasks demand excellent aerobic efficiency for success. Meaning the efforts the athlete needs to make, must not take so much out of the athlete, that they cannot repeat them, and that they cannot complete the total workload at a high effort. It is 3000 to 5000 kJ of energy demand, and meeting that demand is the baseline minimum. This is in contrast to say a short track or cross country MTB race, where as total workload goes down, the absolute intensity goes up. In both of these races, a big common factor is that the driver in the result is not absolute, one time, power for say five or twenty minutes (more like a TT or a shorter event), but the ability to absorb a large workload and then go fast enough to be competitive. In a lot of ways I think about races like this as, “weathering the storm” races. Whoever can weather the storm best, and then go still fast, wins.

Now, as the cliché tells us, the devil is in the details. So while on a simple level these races are about the same thing, handling a big aerobic workload, when you drill a bit deeper, the differences show up. First off, just looking at the two power files, visually we see that the road race is actually more stochastic, and just consistently having more oscillations in power. This is a key component of road racing, especially in Europe. You can look at the first 2.5 hours of the race and say, “ok, 220w average, that’s what I train for”. What is easy to miss is, that there is a < 5sec burst over 400w, probably every 5-8 min on average. None of those efforts in isolation are challenging for this athlete, but what they do is add up to a significant amount of cumulative time over threshold, which shifts things metabolically, as well as adds to muscle fiber fatigue. Both of these are things, which are totally manageable, but they increase the carbohydrate/glucose demands on what the athlete needs to take in exogenously, and if they haven’t trained to do the workload prior to the race finish with some of it coming from anaerobic efforts, they will be more tapped than expected. That is an initial big difference right off the bat. The marathon MTB race, you can see the 30 sec and 60 sec peak powers are pretty much the same as the road race, but they happen right at the start and then it’s over. As the race goes on, you can see the file just gets smoother and smoother. The competitive power under fatigue in the marathon MTB race, is a much lower, more aerobic power than in the road race. So not only is the storm to be weathered different in each race, but the “competitive finish” at the end is different. Looking at where the peak powers occurred in the road race, you see the absolute intensity for the 30s and 60s powers are the same, but come much later in the race. Again to try and make things simple (complex can be fun, but simple is productive) the road race gets more intense as the race gets closer to the finish, the MTB race gets less intense and more about diesel aerobic power. The higher the power, the more the effort relies on carbohydrate, simple trend. To the point, if we look at the final hour of the road race vs. the MTB race, the final hour of the road race is almost all power that is either above FTP, or coasting (descending). Whereas the MTB race has a lot less oscillation, a lot less high power effort in that final hour. The MTB athlete can be competitive, on quite different nutrition and ability to tap over threshold powers under fatigue.

So what is the takeaway? Well, I don’t know, two different races, two different detail sets, yeah that’s probably pretty expected. There are a lot of ways you could look at these different files, and ways you could call them similar or different. The big applicable point that I like to draw from them is that a good way to break down race demands may be to break them into two simple categories. The first demand and priority should be what is the general workload (i.e. duration, energy demand, TSS). The second demand and priority should be what is the composition of the general workload. This is where we really start to see the differences. It all feeds back into probably the most basic ideology of endurance sport training, that athletes should start with general preparation and move towards more specific preparation. Now that I have typed all these words and am reaching this conclusion, I am a little disappointed, not to bring something more interesting and controversial to the table. However, often the oldest and most practiced philosophies are the best and most secure. To leave it with a counter I would say that it is never too early in training to start incorporating specificity towards the task demands of an event. It is easy to go overboard with that, and lose some of the key general preparation, but in bits and pieces, why not train specifically for what you’re going to race?

The punch line? 5th in the road race, 1st in the marathon MTB race.



Have Your Holidays and Enjoy Them Too

The holidays can mean a lot of different things to a lot of different folks. For most, it’s a time to celebrate with family, friends, and coworkers. For a lucky few, it’s a time to get that Red Ryder BB Gun they’ve always wanted.  And for some, the holidays represent a time in which it is frustratingly difficult to keep up with fitness goals. 

Throughout the holidays, there is a plethora of food and drinks.  This obviously leads to concerns about weight gain.  The hot thing for blogs this time of year is to tell you how to “hack the holidays”.  These blogs will tell you how to find the best low-calorie options at holiday parties.  However, trying to eat healthy at a holiday party can cause mental stress and that’s exactly what you’re trying to get away from by attending a party.  Plus, that low-cal “healthy” option is probably not worth it

Instead, here at Catalyst, we’re firm believers in moderation around the holidays.  Have some of those sweets and enjoy them guilt-free.  An extra cookie or slice of pie isn’t going to derail all the hard work you’ve put in the past few months.  

Of course, moderation is not the sexy thing to say in this day and age of restrictive diets.  So here are some of our favorite tips when it comes to the holiday buffet table:

  • Eating sweets in moderation does not mean you eat only sweets for dinner.  Add some of those cute baby carrots and fresh fruit slices to your plate.

  • Bring your own healthy options to the holiday party. And just because it’s healthy doesn’t mean it has to be boring! The internet if full of fun ideas like pirate ship pineapple boats…

  • It’s easy to overeat and overindulge at a party if you arrive starving.  Instead, eat a light (healthy) snack before arriving.  Eating something healthy beforehand can also help reduce the guilt of eating that extra bit of dessert.

  • One of the things that has stuck with me from college nutrition class is the saying, “you can always go back for seconds.” Serve yourself a reasonable amount of food and if you’re still hungry once you’ve finished, you can always go back for seconds.  This is better than dishing up too much food as you’ll feel obligated to finish everything even after being full. 

  • Celebrating with some cocktails?  Don’t forget to keep hydrating with water as well.

In addition to parties, the holidays can also be filled with stress.  One way to combat this stress is by getting some physical activity1.  Maintaining your normal workout routine might not be possible though and that’s okay. 

Don’t have a bike with you?  Take some time to walk around the neighborhood.  Don’t have access to a gym?  There are LOTS of great body weight exercises your coach can help you with.  You can also combine family/friend time with physical activity time.  Your “workout” may not end up very difficult but your family/friends will love spending time with you and you just might find you enjoy it too. 

Another way to limit stress is to get enough sleep2.  Nap during travel, nap during the game, nap during dinner… With everything going on during the holidays, you might even need to change your workout schedule so you can get a full night’s sleep.  For any motivated individual, missing a workout sounds horrible, but continuing to workout without the proper rest is not going to help anyone. 

Our last bit of advice?  Don’t go out and survive the holidays.  Instead, go out and enjoy the holidays.  Oh and be sure to save a slice of pie for us here at Catalyst – we’ve got a sweet tooth… Thanks for reading.

Cranking Away

Believe it or not, this marks our fifth post on Catalyst Content. We hope everyone has been enjoying it, as we certainly enjoyed having a spot to do some writing and ranting. If folks have not been enjoying, well we’ve still been enjoying writing it, so we’re still happy. Folks will remember our kick off post was a feature with the charming Matti Rowe, taking a look at one of his favorite workouts. Well, the spotlight turns today to Stephen Bassett, as we ask him the same question.

Stephen is a professional road racer, with the Silber Pro Cycling team. Concurrently, Stephen is a student at the University of Tennessee in Knoxville, pursuing a degree in English. With a big road season on tap, but also a limited of time to train due to school in the fall, getting the most bang for the buck out of his workouts is the key for Bassett. We asked Stephen what his favorite winter workout is, and here is what he had to say:

One of my favorite things to do in the offseason is train with PowerCranks. For those of you who don’t know, this is a crank system that isolates each leg. Both cranks drive the chainrings, but they don’t connect in the middle. This makes it impossible to “cheat” your way around the pedal stroke by compensating with the opposite leg. So, if you can imagine doing single-leg drills, with both legs simultaneously, for a couple of hours, you can see how this is a pretty unique training challenge. I’m convinced that with the proper application they can really help your efficiency on the bike by eliminating wasted wattage and keeping you engaged all the way around the circle. If this all sounds very out there, it’s because this is one of the weirder training methods you can find. They had a brief period of popularity in the early 2000s, but have since faded from favor. It’s a big investment (you have to designate a whole bike for it, plus scrounge around on the internet for a used set) and it hurts a lot for at least 6 months as you struggle to figure out the neuromuscular coordination requirements. I also notably got dropped trying to use them on the Saturday shop ride and have yet to live down the shame.

I started training on the PowerCranks in 2014, mostly inside for the first few weeks. It took about 6 months to be able to stand up on them. At this point I can train on them and not really notice any difference, which is the goal. I like to ride a lot of different kinds of bikes in the offseason (fixed gear, mtb, etc), but sometimes I want to go in too many directions at once. So this year Nate and I decided to limit our focus and felt like the PowerCranks were the most worth spending a good deal of time on. I’ve been riding them once a week, mostly Zone 2 pace. Totally anecdotally, I can tell you that the day after riding these you will feel like a champ back on your normal cranks.

In essence, these things are pretty wild, but if you’re into the unconventional and a lot of pain in muscles that were doing JUST FINE BEFORE, there are gains to be made using them. Plus, you can freak people out by demonstrating the “Kangaroo” pedaling method! Thanks for reading my nerdy but non-scientific assessment of this contraption. I wonder what Nate has to say about them...

As we hit on, while Stephen is in school the aim is really to make every ride count. With the power cranks, every pedal stroke counts, and in that they are super valuable. With all the data we have right in front of us, it is really easy to get so focused on power production, that we can lose sight of the goal of efficient power production. The power cranks, as Stephen said, are super challenging, but they are also really good at building an efficient pedal stroke. It’s not fair to say that we don’t use our technology to work on pedaling efficiency. There are tools like the Pioneer power meters that look at stroke efficiency, and plenty of power meters that measure (or claim to measure – angst) left/right power balance. However, at the end of the day, more often than not the athlete goal is make more wattage. If the wattage is applied super inefficiently around the pedal stroke, athletes might just be burning up a bunch of kJs going nowhere fast – like that badass revving his Camaro at the stoplight – burning some gas for sure, not creating a lot of speed.  Pedal stroke efficiency does not solve the world’s power production problems, but it is probably a piece of the puzzle.

Well, why don’t we just have Stephen ride them all the time, and have a super baller pedal stroke? Everything with an upside usually has a downside. The power cranks are really fatiguing on certain muscles (especially the hip flexors!) so it is easy to overdo it and get a muscle strain. Additionally, the volume and intensity an athlete can put in on them has a relatively low ceiling. At this point (after 3 years of use), Stephen has worked up to comfortably doing 3 hours, all of which is at a comfortable aerobic pace. So if that is our training objective for the day, by all means, the power cranks are great. We get the aerobic stimulus we need, and some bonus muscular recruitment work. However, when we need to focus on higher volume, or higher intensity, or both, the power cranks need to go away.

What can folks do that want to work on the pedal stroke, but don’t want to ball out on a set of power cranks? One leg drills. Someone probably mentioned them when you first started riding, athlete tried a few, and they were not super fun. That did not last long. Well, they are probably still not super fun, but maybe now athlete read this post, wants to be like Bassett, wants to build some pedal stroke efficiency, does some one legged drills. Start out with 5x30 second one-leg drills, at a low cadence (70-80 rpm) on an endurance ride. Build up to doing 60 second reps, at 100 rpm. Need a bit more of a challenge, throw them in as a “bookend” to a long ride – do a set of 5x60 second reps one hour into the ride, and another set 3-4 hours into the ride – see if you have a noticeable drop in cadence on the one leg drills, as fatigue sets in. If you do not, congrats!

Some Thoughts on Load Tracking

        Load tracking has been a component of athletics for as long as we really know, whether it be miles, weight x reps in the gym, hours, or more popularly as of late, effort based metrics like TSS and CTL. TSS and CTL are hugely popular, with both coaches and athletes. I use them myself on a daily basis, working with athletes and training prescription. I think they have a lot of value, however I also see people consistently place more stock in those values than I think is merited. What follows is an open table discussion, between me and myself, about the idea of “load”, is it worth tracking, how should it be tracked, what can we extrapolate from it. Be forewarned, all that follows goes no farther than opinion and trial and error. This is far from an objective science, but potentially that is where the greatest value lies.

Philosophy of Total Load

        Every athlete can run at a given “total load”, which individual to that athlete, let’s call it Load_ind (Load for an individual). Load_ind must consider not just an athlete’s workouts, but also EVERYTHING that adds STRESS to the system, such that components of Load_ind, may include:   

  • Workouts that give an objective load score (i.e. TSS)
  • Workouts that do not give an objective load score, but could be applied a subjective load score (i.e. fatigue ranking, RPE, etc)
  • Relationship stress
  • Sleep quality
  • Work stress
  • Nutrition and hydration state, in relation to optimal, a workout is undertaken in
  • List goes on, but the point being that "total load" must comprise more than what shows up in TSS and/or CTL (or similar such metrics)

        The graphic below shows an athlete, in three different scenarios. The athlete is running at their hypothetical 100% of Load_ind in each scenario, but you can see the composition is different.

Three scenarios, of an athlete at 100% of Load_ind, with varying composition.

Three scenarios, of an athlete at 100% of Load_ind, with varying composition.

        In each scenario, in theory the athlete really cannot take on any additional load, whether it is from training, health, or psychological stress. Certainly, everyone as a coach and athlete, has likely crossed over that Load_ind max point, and typically the result is unsustainable, until we return back below 100% Load_ind. The trap to fall into is thinking that if in June of 2016 an athlete handled “x” amount of training load, with no work obligations, and in June of 2017 an athlete has 20 hours per week of work, that they are going to handle “x” amount of training load in the same. That is a simple example that most people would agree with, but in reality it gets more complex and the lines between where the stress is coming from, and how to manage it, get blurred.

Load as a Tool for Forecasting Performance

        It is becoming more and more popular to use training load (i.e. CTL) as a forecasting tool for performance. When there is a possibility to replace grey area of guesswork, with black and white of trustworthy quantifiable data, I am all for it. However, I would venture to say that using CTL as the main driver in performance forecasting, and the target in driving training, such that the priority is getting CTL to a certain level, that is just trading grey area for a different grey area. Here is why:

  • Load does not account for variances in composition, such that a CTL of 100 can be achieved a myriad of ways
  • Equivalent loads of differing compositions are almost always going to result in different performances, in the same competition context. Load composition is just as important as load.
  • Load, measured as CTL, is influenced to a greater degree by aerobic powers than by higher intensity powers. Such that an athlete's perceived increase in load (and fatigue) for a weekly increase in volume of high intensity, may not be duly reflected in a metric such as CTL.

The Fix

        The reality is, if looking for a black and white, quantifiable metric, there is no fix. As I hit on with the idea of Load_ind, training load is just a slice of the pie. If there is already a lot of grey area in the total load, how much does it even matter if whatever metric we use to track training load is an accurate portrayal of how fatigue ebbs and flows?

        Well, it probably can be a more useful tool the more clear of a picture it paints. My opinion is that the more aerobically driven the training, the more closely a metric like CTL correlates to the performance and perceived fatigue of the athlete.  However, as training gets more “polarized” and incorporates a higher volume of intensity, the correlation starts to decrease. A specific example, we’ve already hit on,  a plateau in CTL, followed by a change in training composition. Athlete’s perceived fatigue changes, as do contextual competition performances, none of which is reflected in any real change in a metric like CTL, ATL, or even TSB. Are there metrics the specifically address the idea of changing how intensity is weighted, in a load tracker?

·      Yes and no. Chris Baddick has really chewed on some of these issues, and created the metric of CIL (chronic intensity load). CIL will display bifurcations from CTL, as the volume of intensity (measured by IF) changes, but Chris will be the first to argue that even IF is a really poor portrayal, as depending on the total volume of the ride, IF can easily be diluted. I continually come back to the idea of eschewing “advanced metrics” such as TSS, CTL, and IF – for more simple measures such as volume of intensity and total volume.

        Looking at training in hours, may be “old school” in this era – but it also seems to correlate, depending on the goal.  Sure tracking training by hours has an even bigger flaw in ignoring composition than CTL does, but if you combine that with weekly volume of time spent in different zones of intensity, maybe you start to get closer? It may not all feed into one catch all metric – but you can also see a black and white change in time spent riding at various intensities. Without diving into too much depth, I can say that after looking at a pool of riders very closely for three years now – continually the metric I see the highest correlation with summer competition performance is very simple, total hours ridden from November to February, of the prior winter.  Maybe cutting out the grey area means going back to simpler, but more black and white, metrics?

        The bottom line is that, no metric is perfect, and never will be. We can spend time tweaking the metrics to try and get them closer to perfection, but for me the whole idea of thinking about a “total load” – Load_ind – is that metrics do not, and will not ever paint the whole picture.  At the risk of now sounding like an infomercial, that is the value of a coach, in my opinion. The role of a coach should be to get much deeper than what is displayed by the popular metrics. The role of a coach is to cut through the grey area – which usually takes some trial and error, and it may take years for a coach and an athlete to build their successful model [aside - successful model is a total unicorn in my opinion, and if you believe you have one, you are settling]. If eliciting top performances was as easy as correlating it to a given training load, no one should have a coach. It’s not to say that having a coach all of a sudden makes it easy – but perhaps with the right relationship an athlete starts to get closer? The counter to that is that a coach can only be successful with clear athlete communication, due to the highly subjective, and oscillating, nature of everything that contributes to Load_ind. Good luck finding perfection, I certainly plan to keep searching!