CrossFit incorporates many facets of athleticism like strength, power, speed and endurance. As the sport has progressed we’ve seen an evolution in the athletes with regards to these attributes. CrossFit games data show that male and female athletes have consistently added around 15 lbs to their Olympic lifts each year. As these power numbers have increased there’s been simultaneous improvements in times for conditioning benchmarks like “Fran” and “Grace”. What this means is successful CrossFitters require increasingly high levels of power and conditioning. The caveat is both systems must be developed to high levels without hindering each other, this requires efficiency and planning.
CrossFitters require development of all three energy systems: Adenosine Triphosphate-Phosphocreatine (ATP-PC), Anaerobic and Aerobic. The ATP-PC system fuels all movements during the first few seconds, this is the power energy system. The ATP-PC system will be used most during explosive exercises like performing olympic lifts. The Anaerobic System as the name implies is done without oxygen and relies on burning glucose for fuel, it usually lasts from around 20 seconds to 2 minutes. This is the dominant system during many popular time trial WODs. Developing this system is crucial for success, athletes unaccustomed to the lactic acid build up in the anaerobic zone will gas out. However training the anaerobic system is very demanding and can impede progress with other athletic goals if the training volume for this system is too high. The aerobic system uses fat as the primary fuel source, this system is the primary base for the sport of CrossFit. While specific qualities like strength, power, speed, etc are all highly valued most events will require some degree of aerobic endurance work. The Games consist of multiple events held across an entire weekend, without a large aerobic capacity it becomes difficult to compete at a high level during events in the later stages.
It’s important to remember the energy systems are not an on/off switch: While the systems are typically split up into separate groups, they actually flow into each other. As an example our aerobic system is at work when we recover from sets of anaerobic work. In CrossFit, different elements of each energy system are present in most events. Development of each energy system is needed, athletes would benefit from training each energy system independently and together. A conditioning strategy can be to develop general capacities of the energy systems independently (ATP-CP, Aerobic, Anaerobic) with a focus on individual weakness for the specific systems and then a gradual integration as competition nears. This could mean incorporating things like EMOMs, Ladders, and Complexes during the later stages of your training phase.
Balance The Energy Systems: Similar to lifting, conditioning work requires a balance between intensity, volume, and frequency. As one variable increases there needs to be a decrease in the other variables. CrossFit requires a high degree of frequency and volume because of the wide range of skills that must be developed, intensity should be used judiciously. One conditioning strategy to use is to program energy system work as a compliment to strength work by taking into account the intensity, volume and current frequency of your strength phase. This could consist of sub-maximal aerobic training days with targeted maximal days(anaerobic work). And the use of tools that can aid anaerobic training without hindering strength gains like sled pushes and loaded carries.
Efficiency: Improving efficiency with different modalities used in competition is crucial for success. Inefficient technique means you’ll be more susceptible to injury, have suboptimal performance, and burn more fuel than necessary. For multi-event/multi-day sports like the CrossFit Games, efficiency is a necessity so that you can apply more energy reserves towards the most stressful events. A high level of movement efficiency will also allow you to increase work capacity during training phases, in other words it gets easier to get more work done the better you get. Improving technical mastery in commonly used movements(olympic lifts, running, rowing, etc) will go along way for enhancing aerobic and anaerobic conditioning.
Take Home Points: CrossFitters are getting increasingly stronger each year with large work capacities to match. Target individual weaknesses in each energy system and then integrate the systems for more event specific work as competition approaches. Balance energy system work by accounting for your program’s total volume, intensity, and frequency. Increase exercise efficiency, the easier a movement becomes the less energy currency you have to spend on a workout