It’s time for another rant:

First, watch Mike Boyle’s video in which he says Aerobic base training is useless:

The problem with this guy’s view:

VO2max is NOT the measure for aerobic performance or capacity. I’ll post later on why his reasoning for intervals improving VO2max is faulty. I’ve got a whole paper on that coming up, so we’ll leave that for next week…

Studies demonstrate that his so called “interval training” produces better results when preceded by a period of aerobic training. Or in regular terms, having a base of general aerobic work enhances the benefits from interval training.

He also underestimates/ignores the aerobic component of most sports. Even intermittent sports like basketball or hockey have a large aerobic component. Yes, doing interval training is necessary for these sports because it is going to be pretty specific. The problem is that there is this infatuation with specificity. As track coaches, we know it’s important, but it has to be supported. You wouldn’t have a miler run a mile as fast as he could most days or even do only intervals at mile pace. The same thing applies in intermittent sports. You need some general aerobic conditioning to support the interval training. Research clearly shows that performance in intermittent tests/sports is significantly related to aerobic capacity and something that is basically the velocity at VO2max.

Also, consider what impacts the ability to repeadetly go hard for let’s say 60seconds and then rest for a couple minutes? Well if you’ve ever done miler type training, you know the ability to recover between bouts is crucial. The ability to drop the heart rate, clear lactate and H+, use lactate as a fuel source, restore Creatine Phosphate, etc. all significantly impact the ability to do the next interval fast. What impacts all of these mechanisms? the aerobic system. Research has shown that Creatine Phosphate replenishment is strongly tied to the aerobic system.

Similarly, if we look at recovery in terms of Excess post oxygen consumption. The larger EPOC, the longer it takes to “pay it back” or recover. What minimizes EPOC, a quicker VO2 response, which happens due to aerobic training.

You could go on and on with how endurance training increases lactate removal, or how aerobic capacity has been shown to be significantly related to a decrease in speed during all out interval training.

We know that interval training and longer training can impact the same endurance adaptations (i.e. mitochondrial oxidative capacity, improved fat oxidation and glucose transport). However, what is largely ignored is they do it through different signalling pathways. Laursen wrote a wonderful paper on this that has yet to be published, which I’ll hopefully discuss later when it is.

The problem with Boyle’s stance is that he takes an absolute stance. And his central premise is that VO2max=aerobic performance which it does not. Read one of my blogs below for a brief glimpse into that reasoning. There is a trend in strength/sprint training people to think that interval training is equal to endurance training in terms of aerobic performance. THe problem is that this is largely based on VO2max only. Which is complete crap. As I said earlier, more on this later in the week, so you’ll have to trust me till then.

(Note: There aren’t really FT-b fibers in humans, but since everyone uses it, for this rant I’ll use it)

The guy doesn’t understand muscle fiber changes. Even if all you did was sprint training, you would still get a shift in fiber type towards more intermediate FT-a fibers. That’s right, FT-b fibers would shift to more “aerobic” FT-a fibers. Does that mean force decreases? Not necessarily because other factors change along with that.

The conversion of Ft-a fibers or intermediate fibers to ST fibers is EXTREMELY hard. It takes a long freaking time. In animal models the only way this change occurs, even with chronic all day stimulation for months, is if damage the muscle fibers. The change from FT-a to ST is extremely tough and takes years of consistent aerobic work. It’s one of the reasons why endurance athletes (marathoners in particular) are able to hold on to peak fitness in later ages than power athletes.

This fear of conversion also is rooted in the idea that fiber changes are everything. They are not. There are many different ways to classify fibers and the characteristics of each fiber are not as defined as some people make them out to be. Certain aspects of the muscle fiber are going to change before other do. Fiber type percentage is but one variable out of many that affect the power of that muscle.

The problem is that because it has been measured so often, we focus a ton on it. So it has created this whole fear of conversion. Is too much aerobic training good for a sprint/power athlete? No. If all they did was run 30min a day, I’d say, yes you might be concerned with some changes that might decrease power. However, that’s not how any sprint/power athlete trains, ever.

Let me ask you track guys to use your brain. Do you get scared of fiber type conversions when you have your distance runners do hill sprints once or twice per week? No, because it’s surrounded by enough endurance work that it doesn’t matter. Now, if all you did was sprints every day, then yes, that might be of concern. But who actually trains like that?

And on that subject he quotes Charlie Francis who he says is the greatest sprint coach in history….except that all his athletes took drugs. That should be your warning sign right there. How did his athletes become world class? They took more drugs than anyone else and it showed in how crappy they performed off them (ala Ben Johnson). Maybe Charlie Francis should have done some easy 20-30min runs or aerobic 800’s like Carl Lewis and Leroy Burrell and that group then they could have progressed cleanly.

And lastly, he hates on Cross Country. Now is cross country something that should be done for sprint athletes? No, it’s too much of one stimulus. But it didn’t seem to hurt Kerron Clement or Bershawn Jackson too much running CC in HS…

Be very wary of coaches who take absolute stances. You see this with many sprint coaches and strength coaches now a days. They are terrified of fiber type conversions, when in reality it is just a gross simplification of the process. Fiber changes are very complex.

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    1. Anonymous on December 3, 2009 at 12:03 am

      Very very good post

    2. john on December 4, 2009 at 12:35 am

      Great post. Did you email Mr. Boyle? I'm pretty sure you could put up a good argument against him. I emailed him about his video and he actually emailed me back, but I don't know nearly as much as you. I was just curious if you did.

    3. Tony on December 7, 2009 at 4:28 am

      "And on that subject he quotes Charlie Francis who he says is the greatest sprint coach in history….except that all his athletes took drugs. That should be your warning sign right there. How did his athletes become world class? They took more drugs than anyone else and it showed in how crappy they performed off them (ala Ben Johnson). Maybe Charlie Francis should have done some easy 20-30min runs or aerobic 800’s like Carl Lewis and Leroy Burrell and that group then they could have progressed cleanly."

      You have a pretty good post going, but then give your own gross over simplification of the process. Ben was not the only sprinter charlie PRODUCED! Additionally he has done a tremendous amount for the sprint community and runs a great site at

    4. stevemagness on December 7, 2009 at 4:17 pm

      Thanks all. I haven't emailed mr. Boyle.

      Tony- I've read both of Charlie Francis booksm, and been to his site, and he does have some good things to say about sprint training (I don't think his biomechanics section was that good). However, one has to ask if his training as a whole was sound or not because of the drug issue.

      I know Ben wasn't the only athlete he produced. I'm not aware of all his athletes. All I know is that of his prominent WORLD CLASS athletes, they were on drugs. Ben Johnson, Desai Williams, Mark McKoy and Angela Issajenko were all drug users.

      So, the conclusion I come to is that Charlies big name athletes were on drugs.

      Those are the only 4, truly world class athletes I know of Francis coaching. I might have missed some, but his big 4 were on drugs. What that tells me is that he wasn't confident in his methods getting his athletes there drug free, so why should I.

    5. Anonymous on December 25, 2009 at 11:37 pm

      i wouldn´t ever dare say that e.g. Carl Lewis and Leroy Burrell didn´t cheat with drugs.
      It is pretty strange to read that trainers that don´t fit into a hypothesis are only discerned from other trainers of having prescribed drugs. it´s common sense that pretty all world class athletes are in close relation to performance enhancing drugs. so there is no need for this sort of hypocrisy.

    6. stevemagness on December 25, 2009 at 11:45 pm

      Leroy Burrell was my head college coach and the coach of both of them is a good friend/mentor. They weren't drugged up like Ben Johnson.

      As I said, every good athlete CF has coached to an elite level has been a drug user. Sorry if that makes me doubt their competence as a coach. If you don't have confidence in your athletes and your ability to coach that you need to resort to cheating, why should I have confidence in their methods.

      It's like most of the east german/Russian coaching info. People used to seek it out like it was gold, especially the sprint stuff. But look at the results of athletes who who have been clean…

    7. Anonymous on December 29, 2009 at 10:54 pm

      "And lastly, he hates on Cross Country. Now is cross country something that should be done for sprint athletes? No, it’s too much of one stimulus. But it didn’t seem to hurt Kerron Clement or Bershawn Jackson too much running CC in HS…"

      I think sprint athletes should run xc if the xc coach is willing to make some adjustments. I encourage sprinters to run xc and we have them do different workouts on our quality days that are more speed-based. They will run with the rest of the team on recovery days so they get in some aerobic work. We have found that our sprinters have gotten noticeably faster since we started this. As you have stated many times, it is hard to pinpoint the specific physiological advantages or disadvantages of any training system. I think xc helps them become better sprinters because they are putting stress on the systems and muscles/tendons they will use in the spring.

      Many xc coaches are not willing to make changes for sprinters. Too bad, because now the sprinters are doing nothing or playing another sport that may not help them develop as a sprinter. We require the sprinters to run at least 4 meets. I think that is a reasonable request and keeps the integrity of their membership on the team intact.

    8. SANDY!! on October 21, 2010 at 4:14 am

      First time reader and I am in love! Could you please talk more about motor unit recruitment? It seems to me that all training begins with MU recruitment. Do the better runners, with good form and without, have the ability to recruit a greater number of units earlier in a race? And, then, are those units able to work in less than perfect metabolic conditions?

    9. Anonymous on October 8, 2011 at 1:34 am

      In the post you metion that it would take a really long time to change from FT to ST and you mention animal models but is there any solid evidence this occurs in humans? It would be useful and helpful for your readers if you discuss/mention or clarify that characteristic of the fibers, such as enzymatic profiles, mitochondria densioty can change in the absence of changes in mysoin expresssion. Fiber typing my the type of myosin seems more relaible than looking at other common features of FT and ST fibers. Not to be too picky but I don't think it's clear that damage is required for fiber type switching.

    10. Will on November 12, 2011 at 10:21 pm

      just found your blog. great job in covering the details. look forward to reading more.

    11. Scott on December 21, 2011 at 8:54 pm

      The only human study i can think of that actually showed fibre type conversion (#, not relative amount) was done on elite Norwegian cross country skiers. The time course was something like 8-12 years of continuous training. Doing a 6 week block of aerobic training is not going to condemn you to a life of "slowness".

      You are also right about the IIx to IIa shift. Studies show that when untrained subjects do ANYTHING, fibres start to take shift to "IIa". Detraining studies (Casting, immobilization, etc.) show a tendancy to shift to IIx. This is why IIx fibres are sometimes called the default fibre type. All you are really doing to get IIa fibres is giving them a little bit of oxidative support, so they can sustain force for a longer period of time.

      Boyle also apparently has no knowledge of the central (chamber volume, EDV, SV, pulmonary adaptations) and well as peripheral (capillarization, etc.) adaptations that result from "aerobic" base training. These are long lasting, albeit more time consuming to come by than improvements seen with interval training. Interval training does show faster improvements in some areas, however those improvements plateau after 4-6 weeks of training.

      This emphasiszes the need for periodization in sports. You can't do the same training… all the time… and expect to continue improving.

    12. Drew Seaver on July 16, 2013 at 1:02 am

      Coach Mike Boyle is a strength coach for skill-sport athletes – So all your points are valid, except the fact that you are relating what he says to distance athletes, when coach mike boyle himself admits that distance athletes (obviously) have to run distance. Kind of comparing apples to oranges here. You train distance runners. He is a strength coach and is easily the leading expert in his field today. His job is to keep people healthy and playing in their sport and as a byproduct of that: improve performance.

      So for someone who's job and business rests on keeping athletes healthy, why wouldn't he lean more towards interval training (less repetition) and not steady state? After all, the injury rate in the endurance world is very high, and it all stems from overuse.

      It's always important to critique and it's obvious you are very intelligent, but so is mike boyle and he does have the credentials to show for it, so I wouldn't just dismiss his approach.

      Personally, as mentioned above, I think you should reach out to Mike Boyle and discuss it.

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