Waaay back in issue 11 I introduced some material I called the Power Bias. In that issue we looked at some strategies for pushing power output of CrossFit WODs further towards max power. To do this I encouraged the use of ballistic/plyometric type movements such as clapping pull-ups and push-ups, jump squats and medicine ball throw sit-ups. This month I want to look at a few ways to squeeze more juice out of your programming by examining intervals in the context of mixed modal training. Some might call it intervals within intervals. These people are myopic, sarcopenic and generally do not get out much, but that is the gist of this piece. What I am proposing straddles a no-mans land between metabolic conditioning and peak power production. I’m a greedy, biased bastard (at lest where power is concerned) and I want it all.

First I want to sell you on why this is a good approach, and to do so we need to look at some key elements such as peak and average power as well as a few other goodies.


First There Was Matter And Energy…

I’m sure you folks remember that Work is defined as Force X Distance (w=fd) and Power is work per unit time (P=w/t). Contrary to propaganda from the Young Physicists Association of America, spouting these equations willy-nilly will not help your dating life. They do however help to conceptualize relative work and power outputs. Work is typically associated with some measure of power, as any activity requires some amount of time to complete. Thus, whenever we measure or think about work, we should consider power as well. OK, if you are still awake I do not think there are any arguments about the Wee-Ones physics lesson. So here is my main point: If power output is synonymous with intensity (this works for Pavel-esque definition of percentage of 1 rep max, but I am thinking more along the CrossFit/HIT puke in your shoes scenario) what is our best approach to optimizing power output and the associated adaptations? Also, what is most important, average power or absolute power?

Let me use the CrossFit classic Helen (3 rounds for time of a 400 m run, 21 1.5 Pd. KB swings, 12 pull-ups) as an example. The world Record (to my knowledge) is 7:35 by Greg Amundsun. That is flat out moving, but let's look at where time is allocated in this workout. Three rounds of 21 KB swings and 12 pull-ups means 63 kb swings and 36 pull-ups (we will look at the 1,200m of running broken into 3 pieces in a moment). From video analysis, KB swings and pull-ups require 1.25-1.5 seconds per cycle. For this analysis we will assume a bit slower cycle time on these movements. The reason for this is that a multi round workout of this type necessitates a moderate (relative) approach if one is to survive and turn in the best AVERAGE time. Although this is a grueling workout, I’m not sure it is where maximum adaptations lie… but I’m getting ahead of myself.

Back to accounting: we are looking at 99 total movements performed at an average rate of 1.5 sec/cycle with a total time spent on pull-ups and swings of 148 seconds. This is an estimate, but again, from video analysis this is quite close. Now, Greg completes this workout in 7:35 which is 455 seconds. If we subtract the Pull-up/swing time from the total, we will have the time to complete all three 400m runs (455-148=307 seconds). Dividing 307 by 3 gives us an average 400m time of about 102 seconds. Like I said previously, that is really moving, and that time represents a remarkable degree of power output, ON AVERAGE. But what if this scenario was altered a little? What if Greg performed the same amount of work divided like this:

400m SPRINT- 2 Minutes rest
21 KB swings AS FAST AS POSSIBLE (1.25s/cycle)-2 min rest
12 pull-ups AS FAST AS POSSIBLE,-2 Minutes rest
Repeat the circuit 2 more times.

This alteration brings 400m times down to the 60-70 sec range, and cuts 0.25 second off each swing and pull-up repetition. In essence, peak power is greatly increased.


Lucy, You Got Some ‘Splainin

Now I need to back up a little and make the point that mixed mode (classic CrossFit) training is both hard and efficacious. Taxing one energy system/movement pattern and then shifting to another to increase systemic demand is good stuff, but the power output and potential adaptations of the 7:35 Helen vs the Interval Helen are similar to the differences between the mile and 200-400m sprints. Bold statement? Not really, just a Power Bias. “We” (coaches, scientists, smarty pants PMenu readers) have known for a very long time that interval training is beneficial for building endurance at both high and low power outputs. More recently, a study in the Journal of Applied Physiology showed that bouts of 30-second sprint intervals produced marked improvements in aerobic capacity. You may be wondering what the hell happened? Weren’t we talking power? Now “aerobic capacity” is tossed around? Well, yes. It’s a dirty word (or concept), but I’m interested in how we can have the best of both worlds. How can we be strong, explosive AND have crushing levels of cardiovascular capacity. There are limits to this scenario, and I will touch on that later, but see if this all makes sense, then go out and try it and see what happens. For now, look at what Stephen Seiler has to say about intervals.

So back to the interval Helen. Why might this approach be efficacious for improving power output? Why might one want to allocate some training time to this interval-interval format? One answer comes from an editorial in the same issue of the Journal of Applied Physiology as the above study and is actually in response to those findings. Loads of good information can be found in this editorial but the money shot is most assuredly this paragraph:

“It is likely that the potency of all-out sprint interval training is derived in large part from the high level of motor unit activation. All-out sprint training especially stresses recruitment and adaptation of type II (i.e., fast twitch) muscle fibers that are remarkably and equally responsive as type I (i.e., slow twitch) muscle fibers in their ability to increase mitochondrial enzyme activity to high absolute levels (4, 5, 7). In fact, the low-intensity aerobic exercise that is typically prescribed for endurance training or health is not very effective at increasing aerobic enzyme activity in type II muscle fibers, which comprise approximately one-half of the fibers within the thigh (vastus) and calf (gastrocnemius) muscle in most people (6). Thus low-intensity aerobic training is not a very effective or efficient method for maximizing aerobic adaptations in skeletal muscle because it generally does not recruit type II muscle fibers”. [bold words my emphasis]

One finds maximum adaptations ONLY when one achieves maximum recruitment of the fast twitch fibers and this can only happen for limited periods of time (intervals) otherwise power output (fiber recruitment) drops below what is likely an optimum level. If we segment mixed mode workouts like Helen, we can reach near maximum power output many, many times on a variety of movements. That’s the theory. Our clinical experience has been interesting for both our top-end and raw beginners, and it reflects self-similarity. Our top-end athletes find the interval Helen to be brutal. They report peaks of discomfort not achievable with the standard Helen in which one endeavors to clock the best average time. That said, the small break between elements allows for some relief and the thought, "Just a little more, then I can rest." Most importantly, most have found an improvement in the non-interval Helen after a few exposures to this variant. For our beginners, comments are along the lines of, "The workout seems less overwhelming." Our beginners clock greater peak intensity both in magnitude and duration with this method. As I think all of you know, intensity is where we find the adaptations which we are interested.

A great question is why is this format not used more frequently? This format does not lend itself well to large groups. Timing every interval becomes impossible unless a large wall clock (or wrist watch for each client) is used and the clients track their own rest intervals. The second problem with this method is it does not create a “top dog”. If the focus is “who is elite among this group” the interval method is decidedly unsatisfying. Noting beats a pack of people starting on a foot race and encountering obstacles in the form of pull-ups and KB swings! People will even watch marathons on television! At the end a definitive winner is established, as are the also-rans. This format can be a powerful motivator but if one has shifted coaching to one-on-one training, the interval method can bring about this competitive edge by pitting the client against SELF. Each round is an opportunity to best previous efforts and it affords the coach greater opportunity to provide performance crucial cues. We use 1-2 large group, classic CF style WODs each month as a “Game Day” workout… but that is another article.


Outer Limits

When the term “Elite Fitness” or “Elite Athletics” is tossed around, it is important to define the testing parameters. For example if you hear the phrase, “We have the fittest athletes in the world…” I think it quite important to ask the question “Fit for WHAT?” I think the CrossFit definition of fitness (http://www.crossfit.com/cf-download/CFJ-trial.pdf) is the most all encompassing I’ve ever seen. Arthur Devany offers a similar definition and I think both border on genius. That’s nifty, but what if we are talking the elite levels of Olympic lifting, 100-200m sprinting, high jumping, javelin, shot-put and a host of other activities? Being “Fit” for these activities means having a mountain of type IIb (fast, non-oxidative, easily fatigued) fibers. If one is born with a bunch of these highly coveted fibers and one engages in loads of sprint intervals, Fran’s, Helen’s… essentially bathe the muscle in lactate, this person will now be fit for MMA, boxing, and being a cop, but they are most assuredly NOT fit for elite power sports. Does this type of mixed modal training have application with these athletes? Sure, off season, changing things up, addressing body composition issues and improving connective tissue integrity, but drop a few of these WODs into the lineup a few weeks out from competition for a power athlete and watch a contender become an also-ran.

Some have mentioned success with powerlifting and the use of mixed modal activities, but the powerlifter simply needs to complete the movements under any time frame, frequently up to 5 seconds for max efforts. When type IIb fibers are taxed, they convert to more fatigue resistant type IIa fibers that are slower (lower power) but are capable of the same maximum force. This works for powerlifters as evidenced by WestsideBarbell (http://www.westside-barbell.com/) and their successful inclusion of copious GPP and lactate tolerance work. Power athletes of the types I’ve mentioned, however, cannot tolerate this fiber conversion if they are to be “elite”. Some have also made the point it is important to be a craftsman and not a tool peddler. Too true. This must be said of mixed modal training. It is a tool that is enormously beneficial when used appropriately. It is not, however, the cure for all ills athletic.


Wrap

In simple terms “we” will never have the power capabilities of true power athletes using mixed mode activities. That said, the only way to push the envelope and have as much of both worlds as possible is to strive to be stronger at fundamental movements. This can be achieved by an integrated approach such as the ME Black Box or blocks of training alternating between max strength development and strength-endurance (metCon) work. Ultimately the movements used within metCon activities must shift towards those activities that allow for peak power production if we are to become truly Power Biased.