Every muscle contraction in the body is the result of a molecule called adenosine triphosphate (ATP). When the ATP is combined with water it splits apart and produces energy. ATP is broken down during a muscle contraction into adenosine diphosphate (ADP). However, ATP must be replenished for work to continue so another chemical reaction adds phosphate back to ADP to make ATP.
There are three energy systems that produce ATP.
The first being ATP–CP also know as the phosphagen system. Phosphocreatine, which is stored in muscle cells, contains a high energy bond. When creatine phosphate is broken down during muscular contraction, a large amount of energy is released. This happens in very short time durations like squatting a one rep max or short sprint.
The second is known as the glycolytic system that comes online after the ATP-CP systems expires. The body supplies glucose from glycogen stores in the liver and muscles that can be broken down to create ATP. Remember, like the ATP-PC system, the glycolytic system does not need oxygen for glycolysis. This system takes over after about 30 seconds of sustained work. Lactic acid is produced via the Kreb’s cycle as the muscle fatigues.
The third system is the oxidative system or what is commonly referred to as the aerobic system. This system is a low power system that creates ATP at rest and during low intensity exercise. Fats and carbohydrates are the primary substrates that are used to convert to ATP.
We hear all frequently about the first two systems but why would it benefit a football player to develop his aerobic (oxidative) system?
The oxidative system is vital to producing ATP for long periods of time. Developing a more efficient aerobic system will aid in recovery for more intense bouts of exercise by making your body’s ability to transition between different energy systems more efficient. Also aerobic capacity training helps develop cardiac output. Keeping intensity low will drive a maximal amount of blood through the heart and make a more efficient left ventricle. Thus moving more blood with each beat and making for a more efficient heartbeat.
Aerobic work assists the autonomic nervous system composed of the sympathetic and parasympathetic systems. It helps by calming the sympathetic nervous and reducing that “on” feeling that we get when performing any HITT or heavy rep maxes.
By creating a wide aerobic base with your athletes will result in faster recovery between heavy bouts of ATP-PC and glycolytic training efforts.
I personally fought against this for years believing that training slow made me slow and the best way to train the aerobic system was with heavy glycolytic work.
While doing some research on myself and training group we found there was a direct correlation between my strength and my aerobic base. I started doing 30 minutes of aerobic work three days a week at 70% of my max heart rate (130 BPM). I would alternate between walking with a 50 pound weight vest, Assault bike and doing GPP med ball work were I would move continuous for 30 minutes similar to what Charlie Francis would prescribe for his sprinters. I would test rep maxes and max rep sets each week and found as I pushed my conditioning to 5 days a week I made strength increases.
I found the increased conditioning allowed me to recover between sets and workouts. And paid dividends out of the gym as my sleep improved and I felt more rested.
The more interesting byproduct was the decreased body fat and better processing of carbohydrates - usually I feel sluggish and bloated after eating carbs but found this not the case when doing more aerobic work.
While what I did was more extreme, I believe three 30 minute bouts of aerobic work a week would benefit football players in the off-season and especially during the season.
In retrospect, I should have jumped on the Assault bike after each game for 30 minutes of aerobic work to help with recovery and clearing lactic acid and soreness from the body. I believe this with the use of an EMS device, like Power Dot, would have produced significant dividends in my NFL career.