Pawel Krotki-Borowicki
Desirable Difficulty.
The concept of 'desirable difficulty' in performance training is a vital approach for achieving long-lasting results. Current research uncovers the secret of mastering skill acquisition in sports and offers an understanding of the principles for effectively implementing difficulty in various training contexts.
Challenging the Learner.
Desirable difficulty refers to training conditions that stretch the learner's comfort zone and require more effort but ultimately lead to better retention and transfer of skills. This concept is based on the premise that easy, repetitive practice may not be the best way to achieve long-lasting learning outcomes.
Desirable difficulty, in general, requires a coach to practice various skills in a mixed order, rather than focusing on each skill separately through blocked practice. This means that instead of practicing one skill repeatedly in a row, the trainee would alternate between different skills in a prescribed order or randomly.
By switching between these skills during the practice session, players face a more challenging and engaging training experience, which ultimately leads to better retention and improved performance outcomes.

■ Visual of various session perspectives with different order strategies for skill training blocks. The schema provides simple examples of adjusting the session complexity based on skill difficulty levels, tailored to the individual performer's abilities to learn effectively from the challenges presented.
□ The letters represent abstract tasks that make up the complete skill set of an athlete, with letter 'A' being the simplest and progressing in different difficulty characteristics of movement as the alphabet advances.
Implementation Guidelines.
The following principles have been identified as effective strategies to introduce desirable difficulty in training for high-performance and skill development:
It is essential to note that the following rules are primarily applicable to skill training in sporting contexts and should not be directly replicated for the purpose of strength and power development in the gym environment, which – by nature – tends to be more repetitive, more predictable and much less varied as skill-oriented exercise.
Variable Practice: It’s a technique that involves mixing different types of practice tasks or content, rather than focusing on one type of task or content at a time. Research shows that adding variability can lead to better retention and transfer of skills in both perceptual-motor and cognitive domains. Although it may initially seem counterintuitive and less efficient than blocked practice, variable practice has been consistently shown to benefit learning by mimicking real-world situations that require the integration and application of multiple skills.
Distributed Pracite: Spacing practice sessions over time, rather than massing them together, leads to better long-term retention and performance. Incorporating delays between learning and retrieval attempts can enhance long-term retention by making the learner work harder to recall the information. The repetition of motoric skills serves a similar purpose to mnemonic techniques (flashcards), as it adds an additional layer of automation to the particular movement behaviour with each set of reps.
Testing Blocks: Retrieving information from memory through testing or self-quizzing can promote long-term retention more effectively than passive review. Furthermore, spacing out practice sessions and revisiting material after a period of time can lead to a more robust understanding of the content. This effect encourages learners to actively engage with the movement tasks and reinforces the neural pathways required for recalling the information later on.
Delayed Feedback: Immediate feedback during training can lead to dependency and hinder the development of self-assessment skills. Research suggests that delaying feedback and encouraging self-evaluation before providing feedback can help learners become more self-reliant and adaptive. This approach not only increases the difficulty of training but also fosters the development of self-evaluation and self-correction skills, which are essential for success in real-world situations.
Training Under Pressure: In directly competitive sports, athletes often encounter high-pressure situations. Studies have shown that incorporating pressure into training can help learners become better prepared to perform under challenging conditions. By simulating sports-specific scenarios and incorporating elements of pressure, training programs can foster the development of coping strategies and build resilience in the face of adversity.

■ Visual representation of diverse microcycle perspectives, emphasizing the different stages of increasing different levels of training difficulty, based on the principles outlined in the article.
Measure of Difficultness.
Measuring of optimal level of difficulty can be a challenging task, as it requires finding the correct balance between the difficulty of a task and the learner's ability to benefit from it. Based on current scientific knowledge, a few key indicators can be used to assess the effectiveness of desirable difficulty in training:
The rate of errors made by the learner during practice can be monitored. A moderate level of errors indicates that the task is challenging enough to stimulate learning without being too overwhelming.
Measuring the retention and transfer of skills over time can provide insights into the long-term effectiveness of training strategies that incorporate desirable difficulty.
Assessing the learner's level of engagement and motivation during training can also serve as an indicator of desirable difficulty, as more challenging tasks tend to keep learners engaged and motivated to improve.

Imagination of athlete's struggle to comprehend sports-specific tasks in the learning process.
Practical Commentary.
Desirable difficulty in training and skill acquisition is an evidence-based approach that can lead to long-lasting learning outcomes. By incorporating principles such as testing, spacing, interleaving, delayed feedback, and training under pressure, learners can develop skills that are better retained and more easily transferred to contextual situations of sport.
There is no one-size-fits-all approach to implementing desirably difficult training. The optimal balance of difficulty in practice conditions depends on the specific skills being learned, the context in which they are practiced, the instructors and the learners. It is important to gradually introduce challenging elements into the training, ensuring that learners experience a balance of success and difficulty.
Implementing desirably difficult training requires careful consideration of the skills being learned and the specific needs of the learners, but when done correctly, it can result in significant improvements in performance and adaptability.

Recommended Reading.
Ericsson KA et al. The Cambridge Handbook of Expertise and Expert Performance. Cambridge: Cambridge University Press (2006).
Farrow D et al. Developing Sport Expertise: Researchers and Coaches Put Theory into Practice (2nd ed.). Routledge (2013).
Magill RA et al. Motor Learning and Control: Concepts and Applications. McGraw-Hill Education (2016).
Enrich the Conversation.
Respond to the ideas raised in this text by writing to me@pawelkrotki.com.