So here it is guys, the real whole truth about energy system demands in motocross. This is a long one but reading this in its entirety will change what you know about motocross. I know it's a big leap to say that this is the truth and what everyone else is saying isn't but, I truly feel that people have not dedicated their mind well enough to this sport.
What I mostly hear or so is the following; motocross is an endurance sport, motocross is a "mid-range strength sport" and a host of other things. Now I'll start off by saying I'm not the only one with this same view on the demands of the sport. My theory has been backed up by Dr. John Azevedo from Chico State University and one of his friends and professor at another California State University (a former professional racer). Here we go......
Motocross is truly derived from power movements. Think about each time you jump and land, hit a large bump, pre-load off a jump, scrub the bike or hit the whoops. These are very fast movements that require a lot of power and force output in a short amount of time that is repeated for 30 minutes plus two laps. Now think about how your suspension works, it goes both ways. Many time you have to put a lot of strength into your suspension to deal with the terrain, pushing against 100's of lbs of pressure in your forks. Then when you are responding to terrain reversely, you're absorbing 100's or more lbs of force into your body. If you took that analogy and transferred that straight to training you would be somewhere between a power and Olympic lifter. However, that's not the whole equation.
You have to execute these actions 100's of times in a single race and then do it a second time that day. For this reason some people consider this for lack of a better term "a mid-range strength sport". From this people try to tell you that you need to be doing crazy circuits and that these are the answer to motocross because it directly mimics what your doing on the bike. This gets at the idea of specificity of training. While this is great it misses a huge factor that we'll address in the endurance section later.
Now I'd like to quote a man who is considered one of the greatest in strength training and physical therapy in the world. Charlie Weingroff is a world leading expert and one of the most progressive men in the science of the body. In 2013 Charlie said this during a conference,"I don't do sport specific training, I do athlete specific training. The only person who does sport specific training are the coaches of that sport." This is something incredibly true about strength coaches and something many wont admit. They think too much about mimicking the sport rather than focusing on the true demands occurring in the persons body
Many people will still argue this high intensity circuit training focus and nothing else. They argue that it's important for buffering lactic acid and that's a big deal in this sport. Unfortunately lactic acid doesn't exist in the human body, if your up to date with research. We produce LACTATE as a result of breakdown of glycogen (sugars roughly) and it helps to shuttle out the build up of hydrogen ions from the breaking of bonds during natural process of cellular respiration (cells using energy). This lactate can actually be re-used by the body as an energy source more easily than other sources in the body. Excess free hydrogen ions that are not shuttled out by lactate, cause a burning sensation in the muscles as they Decrease your PH levels to more acidic.
Following all of this the endurance equation comes into the mix. The reality of heart rates in the sport is this; you have multiple factors that are not typically aerobically based, contributing to the increase of heart rate. When you lift a really heavy weight, your heart rate increases in the moments following the completion of the exercise. This is part of your bodies natural compensation to rid itself of Co2 bi-product build up. The heart rate also increases as a result of increased motor unit recruitment to supply necessary resources for the bodies output. The heart rate increases for a period of time but, this is not an aerobic specific response despite your heart rate being in those aerobic target zones. During a race you are doing this 100's of times with a short time length between the next effort, causing a recycle in this process. This compounds one upon the other without sufficient time for recovery, keeping a sustained high heart rate.
Now here is the REALLY IMPORTANT part. All of this lactate and complex motor unit recruitment stuff is all dependent upon one major aspect. It is all dependent upon your overall strength and why I referenced early in this piece why Olympic and power lifting is so crucial. THE SINGLE DETERMINING FACTOR OF MAX POWER IS MAX STRENGTH. The "mid-range strength sport" is what is referred to a specialty strength. All specialty strengths are dependent upon MAX STRENGTH. The stronger that you are, the more power you can put out. The more power you can put out and sustain, the easier the stimulus from racing becomes. Resultantly, your required effort from your overall capacity decreases and then the range of effort where you use more precious lactate and build up more excess hydrogen ion decreases. It really is that simple. Then you just need a strong aerobic base in order to recover better between individual efforts and each race, to be more efficient at expelling bi-product from exercise.
So you need to do your cardio and build up your baseline capacity without question. Then you need to get strong, really strong! After this you build up your sustained high intensity capacity and recycle through these processes. All of a sudden, everything on the track feels easier and so smooth. I can vouch for this because I've been there and felt it and it's like you've never felt on the bike before.
