A month or two ago there was a thread about a 100m sprinter and whether he should do Crossfit to help his sprinting. I vehemently argued no that he should NOT do Crossfit, but there were a bunch of people here that said he should and it would build a good base. I recently came across this subject again discussing things and decided to take a little more in depth look at the subject so here's my take on things.
If you didn't read the original thread check it out here before you read this especially as a refresher (wfs):
Actually let me elaborate on something I feel is extremely important where max strength is concerned. As far as most people think, muscle is muscle which is obviously not true as we know depending on the type of strength deficit there is. Sarco tends to have a bigger strength deficit than myo just because myo is stimulated at heavier weights. Let's take this a bit further though. If we look at the types of fibers stimulated in hypertrophy we see that higher rep ranges tend to stimulate more type I fibers as opposed to type II fibers. Type I are the slow twitch more endurance-aerobic-oxidative fibers while type IIA are your fast twitch oxidative and type IIB are the fast twitch glycolytic fibers. Yada yada yada. We know all that right. Okay, now that the foundation is laid let's look at something very important. Here's a good analogy to the point I'm going to make but haven't said: you are what you eat. Everything we eat is metabolized and used as energy or incorporated into our bodies both the good and the bad.
So what exactly does this have to do with training you may ask? Something very important. You are what you train for. Training is cumulative in the sense that you can train for strength and endurance as well as increased muscle mass. Everything we do has a cumulative effect on each of these characteristics. If we look at the muscle profiles of power athletes like elite olympic weightlifters or elite sprinters, we'll see predominately type IIb and type IIa hypertrophy of the muscles. We'll also see a pretty high correlation between applied a large application of power and strength as opposed to say a powerlifter who has very high strength but very little power correlated to the amount of strength he/she has. So if we know this and want to train our bodies to be the strongest that they can be or the best endurance athlete around then mixed modal training is not what we are looking for. This is to say that if someone wants to be an elite sprinter, he would not want to do any if at all endurance-related work in his training. That means no metcons, no aerobic running, no tabatas or anything that promotes oxidative related fitness since the training we do is cumulative on our muscles. Enzyme profiles and fiber type confirm this. If he works with weights with reps between 10-20 RM he is doing himself a disservice by stimulating unneeded and unwanted type I hypertrophy which will inevitably reduce his max potential for type II hypertrophy. That is to say we all have a genetic limit for muscle growth. We can choose what to do with it by training strength/power or endurance. If we choose a combination of both we will never hit a maximum for either one or the other that we choose to work for. Specifically if I used up some of my genetic potential for type I fibers, that's less type II fibers I could have had to increase my explosiveness for sprinting.
So what does this actually mean? If you want to be the strongest you ever can be you shouldn't work much if at all with any type of endurance work. If you want to be the fastest you can ever be you shouldn't be running miles and miles for your sessions nor should you be doing reps over 10. Training is cumulative so it is important to decide what you want to do now rather than later if you want to compete at elite levels.
Crossfit confirms this if you didn't know already. Let's reverse engineering what Crossfit philosophy is to find out why. If you're read the "What is Fitness" from CF's main site which I'm sure you have, I'm sure you'll be able to figure out why. Here's a link anyway so we can look at it (wfs):
The motivation for the three standards is simply to ensure the broadest and most general fitness possible. Our first model evaluates our efforts against a full range of general physical adaptations, in the second the focus is on breadth and depth of performance, with the third the measure is time, power and consequently energy systems. It should be fairly clear that the fitness that CrossFit advocates and develops is deliberately broad, general, and inclusive. Our specialty is not specializing. Combat, survival, many sports, and life reward this kind of fitness and, on average, punish the specialist.
Aerobic training benefits cardiovascular function and decreases body fat – all good. Aerobic conditioning allows us to engage in low power extended efforts efficiently (cardio/respiratory endurance and stamina). This is critical to many sports. Athletes engaged in sports or training where a preponderance of the training load is spent in aerobic efforts witness decreases in muscle mass, strength, speed, and power. It is not uncommon to find marathoners with a vertical leap of only several inches! Furthermore, aerobic activity has a pronounced tendency to decrease anaerobic capacity. This does not bode well for most athletes or those interested in elite fitness.
Anaerobic activity also benefits cardiovascular function and decreases body fat! In fact, anaerobic exercise is superior to aerobic exercise for fat loss! (http://www.cbass.com/FATBURN.HTM) Anaerobic activity is, however, unique in its capacity to dramatically improve power, speed, strength, and muscle mass. Anaerobic conditioning allows us to exert tremendous forces over brief time intervals. One aspect of anaerobic conditioning that bears great consideration is that anaerobic conditioning will not adversely affect aerobic capacity. In fact, properly structured, anaerobic activity can be used to develop a very high level of aerobic fitness without the muscle wasting consistent with high volumes of aerobic exercise!! The method by which we use anaerobic efforts to develop aerobic conditioning is “interval training.”
Basketball, football, gymnastics, boxing, track events under one mile, soccer, swimming events under 400 meters, volleyball, wrestling, and weightlifting are all sports that require the vast majority of training time spent in anaerobic activity. Long distance and ultra endurance running, cross country skiing, and 1500+ meter swimming are all sports that require aerobic training at levels that produce results unacceptable to other athletes or the individual concerned with total conditioning and optimal health.
Just pulled out some of the more important points from there. If you read the whole thing (which again I'm sure most of you have), you'll understand that it is not in a sprinters best interest to be doing CF which encourages a largescale gains in endurance/cardiovascular ability/oxidative ability within the user.
Forgot where it was said but if you do CF you'll be able to outlift an elite runner and outrun and elite weightlifter. True but with CF you'll never be able to outrun an elite runner which is his goal.