Have you ever heard the saying: ‘20% of the effort yields 80% of the results’. Interestingly, this relates to an actual phenomenon known as ‘The Pareto Principle’.
The Pareto Principle’s name comes from an Italian economist, Vilfredo Pareto, who in the late 19th century made the observation that 80% of Italy’s land belonged to just 20% of the population. Surprisingly, this observation is not only present in economics, but in many fields. In fact in science and mathematics, the Pareto Principle occurs often and is referred to as a ‘power law’, which is defined as a ‘relationship between two quantities such that one is proportional to a fixed power of the other’. The Pareto power law can be seen in various aspects of the natural world, from the the proportions at which birds shed viruses ¹ to the formations of polypeptides in our bodies ². Other examples include 20 % of Microsoft’s bugs accounting for 80 % of the company’s software problems. Additionally, in business, many companies acquire 80 % of their profits from 20 % of their customers.
So, what does this have to do with training? Well, the same principle can be applied to the results that a coach’s athletes will see from training; that is to say that 20 % of your training effort will contribute 80 % of your results. Obviously an exact ratio of 20:80 is not entirely accurate, but it is true that adaptations from training follow a pattern of diminishing returns, where every subsequent effort (be it an extra set, rep, exercise, or training session) will have a less significant effect on creating a training effect (Costill et al., 1991; González-Badillo et al., 2005).
Examples of this can be seen in the training literature on hypertrophy and strength training. A meta-analysis from Krieger et al. (2010) compared a single set to multiple sets for strength gains. The image below shows a highly pertinent chart from the research.
The effect size of differing training volumes on strength gains, from Krieger et al. (2010)
If you look closely you will notice that although 4 - 6 sets was the most effective approach, it was a non statistically significant difference from training with 2 - 3 sets. Importantly, performing only one set appears to have been approximately 60% as effective as 4 - 6. We can imagine that if we were to continue increasing the number of sets, our results would become less and less significant. What is likely to be the difference between 9 sets and 10 sets? Perhaps an added 0.5kg to your 1RM? Is that small additional reward from an increase in volume worth the elevated risks? If you are a professional strength athlete then the answer might be yes, however for most sports strength is just one aspect of performance that needs to be improved.
Why then is it that when coaches are tasked with creating a training programme for an athlete, they decide to prescribe a generic volume? In strength training prescription, 5x5 is a favourite of strength coaches, but does the athlete in question need more or less than 5 sets? Maybe 2 sets or 6 sets would be optimal for them.
The questions that more coaches should be asking themselves when designing a training programme are:
1. What is the exact adaptation the athlete requires?
It is of paramount importance that a numeric value is attached to this. Simply setting a vague goal of ‘get stronger’ or ‘increase muscle mass’ makes the task of creating a logical S&C plan much more difficult. A more intelligent approach would be to conduct a needs analysis, whereby the athlete’s current abilities are assessed and compared to the standard for their desired performance in their sport. For example, a prop in rugby competing at the U-19s level may possess a 3RM trap bar deadlift of 140kg. However the standard for a player of his age is 160kg. Therefore his target value to be deemed ‘strong enough’ is 160kg.
2. What is the sufficient volume to elicit the desired adaptation?
As could be seen in the Krieger et al. meta analysis, higher volumes will lead to increased adaptations (up to a point). However, given that more volume requires more recovery time and may increase injury risk, generally it would be illogical to use more volume than is necessary. In the same example of the prop, imagine that he hypothetically has a 12 week pre-season to increase his strength. If we have 12 weeks to make a 20 kg strength increase, then all that is realistically required is a minimum of 0.6 kg (20 divided by 12) increase in strength per week. Therefore the coach would want to just use the amount of sets needed to elicit that rate of progress. Given that most athletes have more than just one physical capacity that they need to improve on, this will free up more time and freshness for other importanr training (e.g. technical, tactical, aerobic, power, speed, etc.). Injury is a key concern here, as reserach has found that a workload that is both too low or too high can increase injury risk (Gabbet, 2016). Instead as practitioners we should seek to hit the ‘sweet spot’ as shown in the chart below.
Figure from Gabbet (2016) showing how Injury risk is elevated when workload is both too low and too high. There exists a ‘sweet spot’, where adaptations are occurring and tissues are not being overloaded beyond recovery capacity.
The important question to ask ourselves as coaches, is how much progress does our athlete really need in the given area? Weight class fighters may be better suited to training with just 1-2 sets to maintain their muscle mass, whereas one seeking to move up a weight class will in a short period of time will want to do more sets to maximise their training return.
Another way to look at this would be your results over time. The beginning stages of training will provide the most rapid results. This is evident in observing the novice effect. When you first begin training, you could shave 20 seconds off your 10 km time every week, and add 5 kg to the bar ever session. As time progresses, your gains begin to slow, and you will find yourself having to put in exponentially more effort to acquire the exponentially smaller results. More detail of this can be seen in the Starting Strength graphic below. This requires more effort in all areas of training and recovery including improved: sleep, nutrition, technique, mental focus, recovery methods, mobility, etc. To make matters more interesting, all of this extra effort also comes with an elevated risk of injury.
The point of this article is not encourage practitioners to use minimal training volume and have their athletes progress at the slowest pace possible. That would be applying the Pareto principle to every single aspect of training. Instead I think the principle should be applied to the entire performance of an athlete. This means that there are one or two small areas that will have the greatest impact on an athlete's performance. For the undersized athlete this will be hypertrophy training, for the slow but strong athlete it will be speed and power training. All that the Pareto Principle encourages is that the coach prioritise training goals, much like a business owner might prioritise a target market.
Costill, D. L., Thomas, R., Robergs, R. A., Pascoe, D., Lambert, C., Barr, S., & Fink, W. J. (1991). Adaptations to swimming training: influence of training volume. Med Sci Sports Exerc, 23(3), 371-377.
Gabbett, T. J. (2016). The training-injury prevention paradox: should athletes be training smarter and harder?. Br J Sports Med, bjsports-2015.
González-Badillo, J. J., Gorostiaga, E. M., Arellano, R., & Izquierdo, M. (2005). Moderate resistance training volume produces more favorable strength gains than high or low volumes during a short-term training cycle. Journal of Strength and Conditioning Research, 19(3), 689.
Jankowski, M. D., Williams, C. J., Fair, J. M., & Owen, J. C. (2013). Birds shed RNA-viruses according to the Pareto principle. PloS one, 8(8), e72611.
Koonin, E. V., Wolf, Y. I., & Karev, G. P. (2002). The structure of the protein universe and genome evolution. Nature, 420(6912), 218.
Krieger, J. W. (2010). Single vs. multiple sets of resistance exercise for muscle hypertrophy: a meta-analysis. The Journal of Strength & Conditioning Research, 24(4), 1150-1159.