Ok. So this post is going to be pretty heavy on the physiology. I’ll try and dumb it down as much as I can, but you may need to hit up the Google Machine if I start using words that seem like i’ve tried to use every vowel within each one. The Googles will help.
So there is a significant trend lately, especially with CrossFit becoming so very popular that says that you only need to go short and super hard to get all the health benefits of both a powerlifter, traditional strength training as well as distance running. Although touted as the all in one treatment, it just isn’t the case. Doing short high intensity interval training certainly does improve your endurance, it makes you stronger and more powerful for time. My focus here is on endurance so for now we can forget the strength components.
Endurance training was traditionally done going slow for long with a few intervals here and there to build some high end speed. CrossFit came along and actually showed that you can do very little endurance or prolonged exercise and when it came to say a 10km or half marathon they could actually perform “ok”, without ever having gone long in their training. CrossFit typically only trains your high end aerobic and anaerobic energy systems as most workouts are just balls to the wall. Both systems seem to work to help build endurance but because CrossFit took less time, it has slowly become the more popular one.
But let me back up. Lets discuss how your body creates energy. I’ll try to keep this simple. Your muscles contract because of a small molecule called ATP. ATP allows your muscles to contract. So for your muscles to contract repetitively you need a lot of ATP. ATP is created via your metabolism. There are two energy pathways that I’ll simply here. Aerobic which is metabolism done with oxygen, and Anaerobic which is metabolism done without oxygen. Both create ATP, but Aerobic creates much more, it just takes longer. At any given time both energy systems are being used, but think of it as a mixture. When you are sitting you are primarily aerobic and doing FRAN you are primarily Anaerobic. It’s during Anaerobic that you create lactate and you can only sustain this level of output for so long before you must stop, or slow down. The key here is a small structure within each of your cells called mitochondria that help to produce the ATP. Your body uses the mitochondria in Aerobic metabolism to create the ATP. The mitochondria can also help to get rid of the lactate and utilize it as energy when its present.
The simple summary. The more mitochondria you have in your cells the more ATP you can create during Aerobic metabolism and therefore the greater your output of energy with less metabolic load. ie. You will increase your output with the same effort. On top of this the more mitochondria you have the easier your body can get rid of lactate and utilize it as energy, allowing you to perform in the anaerobic state longer before you have to slow down or stop. The net effect. The more mitochondria you have, the better your FRAN time.
The question now is. How do I get more Mitochondria!????
Two ways. One is to go balls to the wall, as hard as you can which is why CrossFit does increase overall fitness. The second, and better way to produce more mitochondria is to do what I call Long Slow Distance (LSD). LSD training has been well known in the endurance community for years. It helps to build your “base”. Most CrossFit athletes have zero base. They have no aerobic power. To improve your fitness not only as a CrossFit athlete, but as a human being capable of doing anything physical you need to train long and slow.
So whats LSD look like. Well. How about you go for a 5-10km run at an easy pace 1-2times a week. Do an AMRAP that is 40-60min long that isn’t so crazy that you are standing around trying to recover, but allows you to keep moving throughout the workout. Being able to talk a bit while running is a good gauge as to whether you are going slow enough. If you can carry on a conversation while running then you are going slow enough. If you are gasping for breath every two words, then you are going way to hard!
So to build your overall fitness, and at the minute level increase your mitochondrial density in your cells. Incorporate one to two 60min efforts a week at low intensity. Just because you don’t want to puke at the end of them doesn’t mean they aren’t helping you immensely with your fitness. So go slow and get fit!
– Dr. Adam Wade –
Dr. Adam Wade 