Hi Christian,
I want to ask you your views on this. I’m planning an offseason for a soccer player for 12 weeks. After discussing about energy systems I got the conclusion soccer is alactic-aerobic according the match because a study by Osgnach et al. (2009) performed an analysis evaluating the workload , summarizing that the typical workload of an elite level soccer player consists of the following:
- Total distance of 10-13 km
- Spend up to 70% of the duration of the match in purely “aerobic” low intensity activities, with about 30% consisting of 15-20m higher intensity movements.
- Sprinting ended up being about 5-10% of the total distance covered in a match, yet only amounted to 1-3% of the total match time, which correlated to a 2-4 second sprint every 90 seconds.
So creatine phosphate (PCr) system is the main source of energy within a match during “non-recovery” activities, followed by aerobic recovery. The PCr system will be stressed during the intense activity, with the aerobic system lagging behind, and providing for recovery of PCr stores.
One aspect that I consider is average blood lactate levels of 4.5-5.0 mmol/L, which indicates that glycolytic activity is not consistently high during the course of a match. There are moments within the game that players may reach blood lactate levels up to 10.0 mmol/L, but those moments are rare and depend very much on position.
The soccer player should be training to save such a substrate until deep into a match. An improved ability to utilize free fatty acids and quickly replenish PCr stores will help save glycogen stores throughout competition.
Do you think it is then necessary to have the aerobic power and capacity to help replenish the ATP-PC stores in the alactic system as quickly as possible?
Traditionally, I have seen many strength and conditioning coaches focus their conditioning programs on “anaerobic” training methods, and players with an extremely high anaerobic potential are able to create large amounts of energy during matches but often appear to fatigue faster and typically display higher levels of long-term fatigue in the days following competition. In other words, an overreliance on glycolysis may actually serve to inhibit glycolysis.
Could it be that such high reliance on anaerobic metabolism will decrease RSA, thus increasing fatigue and time needed in recovery?