In the last post we discussed the importance of consistency in training loads, and introduced the acute vs chronic workload ratio (ACWR)(http://www.thescienceofstriking.com/training/applying-the-acute-vs-chronic-ratio-to-combat-sports-part-1/). Initially popular with team sports, the acute vs chronic ratio is now widely used in reference to resistance training and endurance sports. Whilst we don’t presently have any studies referencing its use in combat sports. It makes sense that regulation in terms of training load would be equaling important in decreasing injury risk within this population.
Quantifying Training Load
For those not mathematically minded, The Science of Striking worksheet is a freely available resource that makes calculation of the ACWR and other metrics easy:
For endurance athletes and field sport athletes with access to GPS monitoring, calculation of training load is simply the number of kilometers (or miles) ran, swam, cycled, etc. These days many professional field sports teams will take this a step further by breaking the running volume down into intensities (jog, run, sprint, etc.). Unfortunately for most combat sport athletes a precise metric such as this is generally not available (although there are methods becoming available, which will be covered in the next post). However, I believe we can still glean useful data by simply by recording the number of minutes of total training. This can then be multiplied by the rate of perceived exertion (how hard the session was), to calculate what Foster and others have described as an arbitrary unit of load (AU)1. The rate of perceived exertion (RPE) should be determined approximately 20 minutes after the conclusion of the session where possible, in order to gain an accurate reading. Note that the session RPE is a different metric to the set RPE discussed previously in relation to strength training and testing.
An example training week may look like this:
Skills – 60min, RPE 6
Resistance – 60min RPE 7
Skills – 90min RPE 8
Energy systems – 45min RPE 9
Skills – 45min RPE 5
Resistance – 60min RPE 8
Skills – 90min RPE 9
Energy systems – 30min RPE 5
Multiplying the time in minutes and the RPE gives us the weekly training load in arbitrary units (AU):
Mon: 360 + 420 = 780 AU
Tue: 720 AU
Wed: 405 + 225 = 630 AU
Thu: 480 AU
Fri: 810 AU
Sat: 150 AU
The sum of which give a weekly training load of 3,570
Calculating the Acute Vs Chronic Workload Ratio
The ACWR is essentially a ratio of the last weeks training load in comparison to the average of the last 4 weeks. If the training week above had been performed after previous training weeks of 3,200AU, 3,400AU, 3,650AU in volume respectively, the acute vs chronic workload ratio would be the current week (3,570), divided by the average of the last 4 weeks ((3,200+3,400+3,650+3,570)/4 = 3,455), equaling 3,570/3,455 = 1.03. As you can see, this fits within the 0.8-1.35 ratio discussed above.
However, if the training week above had been performed following training weeks of 2,100, 1,800 and 2,000, then the ACWR would be ((2,100 + 1,800 + 2,000 +3,570)/4 = 2,367), equaling 3,570/2,367 = 1.51. As this number is significantly higher than the recommended 1.35, this acute spike in training load may pose an injury risk to the athlete.
In the last post of this series we discuss some more detailed ways of quantifying training load, and how we apply these concepts to our training plan.
- Foster, C. et al. A new approach to monitoring exercise training. J. Strength Cond. Res. 15, 109–115 (2001).
A full framework of training load quantification is featured in the science of striking, available in both hard-copy and kindle formats (https://www.amazon.com/Science-Striking-Comprehensive-Physical-Preparation/dp/1729586821/ref=sr_1_2?ie=UTF8&qid=1543575646&sr=8-2&keywords=The+Science+of+Striking+Sam+Gilbert)
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