Earlier this week, I was researching the topic of “cardiovascular exercise vs high intensity interval training”. I simply wanted to show that old school, long steady distance training had a great deal of benefits for both the performance focused athlete and the casual exerciser. Instead, I found a whole lot of contradictory information.
Here’s the problem: I know, as a coach of athletes of all different stripes, that if you lack an endurance base, your performance in the gym will suffer. I also know that if you have no previous experience biking, running, swimming, etc., no amount of weight room based high intensity interval training will allow you to complete a long distance race in any of those formats with considerable ease. Training is specific, whether it be movement, intensity, volume, or load, if you aren’t practicing it, its not going to be easy.
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You get better at squatting by practicing squatting. |
1. Strength training
2. Cardiovascular training
However, there are a number of exercise styles that target both of these components and the spectrum of training effects between the two is long and varied.
For example, a beginner weightlifter is going to be breathing pretty hard during his training sessions because he’s doing a taxing physical activity. His heart rate will be up and he will get better conditioned while he gets stronger. A beginner runner will also be taxing her heart rate and aerobic metabolism while also building strength in her legs and back from maintaining upright posture while she runs. A fitness enthusiast who takes his first high intensity interval training class will notice a boost in his overall conditioning while he gets stronger and more cardiovascularly fit, but not for longer durations. Notice something about these three people? They are all improving their overall fitness level. They are probably also improving their health based fitness as well as some performance based fitness.
In other words, exercise makes us fitter.
Science is the research done by exercise physiologists, physiologists, medical researchers, physical therapists and pretty much any organization with a published journal. There are studies on everything from what muscles are stimulated when we jump to how high intensity interval training affects our blood pressure. A lot of these studies are designed to answer a question, but the biases of those asking the questions can significantly influence the outcome based on how the study is set up, the populations used, and the questions asked.
Best practices are the training and coaching practices used in a variety of disciplines that are known to work over time to both improve performance and reduce the risk of injury. Although there may be periodic detours to explore other methods, the core ideas have pretty much remained constant over the decades. Although many of these best practices are indeed the best way to practice, other practices reflect the biases of the participants. Maybe they don’t include certain elements simply because they don’t like it.
Now we have a problem. Because often times Science and Best Practices are in conflict with one another. The important thing to consider with using both of these sources is context. In other words, its not so important for us to understand THAT something worked. Rather we must understand WHY it worked.
If I want to look for the answer in Science, I can find a number of articles on high intensity interval training and how it is superior to low intensity, higher volume cardiovascular training in improving health fitness markers. I can find studies that show that it improves blood pressure, VO2 max, stroke volume, and resting heart rate. I can also find studies that contradict these findings.
I can’t find any studies that show how HIIT alone improves performance over the long term. I can’t find any studies that are carried out long enough to show if there are any detrimental effects such as soft tissue injuries or burnout. I also can’t seem to find out what “untrained” or “well-trained” means in terms of the study participants. Many studies are carried out in non-athletes and are short-term. So, while the researchers are looking at the effects of “High intensity interval training” are, they may simply be seeing the effect of “exercise” in people who aren’t used to exercising. As a biochemist, the study design and context of the results is just as interesting to me as the results and the design of a lot of these studies is lacking.
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If you want to run fast, for a whole game, you must first be able to run far. |
1. Does the study sample reflect the population I am training?
2. What were the baseline fitness levels and additional training activities of the participants?
3. Is there any evidence regarding long term safety and continued improvement in performance?
4. Are there any inherent risks such as overuse and soft tissue injuries that may not show up in the duration of the study?
After you ask yourself these questions, you have some things to keep in mind as you evaluate the progress of your trainees. Remember, its always about training the individual and not everyone is going to have the same tolerance or benefits of a particular training protocol.
Best Practices aren’t going to get a free pass either. Some best practices, such as the use of long steady distance training as the foundation for most endurance based sports, is universally used and accepted by most coaches of high level athletes. Mainly because over the decades, when they divert from this practice, performance suffers. Although HIIT at various levels of intensity are used to enhance one’s speed, power, and overall endurance, best practices dictate that slow and low should be the biggest piece of the pie.
However, in the broader spectrum there are other best practices related to including or avoiding other types of training, recovery, and nutrition that may simply be best practices because they are haven’t been shown to have negative effects. For example, a lot of athletes avoid strength training because they fear injury in the weight room. (And they aren’t wrong, it happens.) However, a good strength coach and a well-designed program in an appropriate sport can not only help avoid injuries, but boost performance as well. Wrong coach, wrong program, wrong sport? Well, that may well be a disaster.
When utilizing a best practice, it is good to ask yourself “why”? Its also good to recognize that you are not going to revolutionize the human body. The body responds to exercise by getting stronger and more conditioned. Focusing specifically on one or the other will enhance that particular focus. Practicing sport specific skills will get you better at your sport. That’s exercise science in a nutshell. So, if something seems out of place, figure out whether or not its actually necessary. It may not be for the individuals you are training at their current level of fitness. For example, if you are training a group of beginners to run a 5k, just plain running is way more important than specialized intervals, lactate thresholds, and tempo runs.
As with the science, ask yourself the same questions:
1. Are the best practices used with the population I am training?
2. What were the baseline fitness levels and additional training activities of the participants?
3. Is the method you are using typically used at a specific time and for a specific duration in a training cycle? If so, when and how?
4. What are the benefits and risks of using this method? Is there a baseline level of fitness or performance that is necessary before employing this method?
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Running is how you build a running base. And its good for your body. |