Book Summary of Peak: Secrets from the New Science of Expertise

12 min readDec 17, 2023

Peak: Secrets from the New Science of Expertise basically makes one simple claim — expertise does not come from innate ability but instead comes from intense deliberate practice over a long period of time. The book starts by defining what it means by “deliberate practice.” Then it pushes back on the idea that expertise depends on innate traits that only a lucky few are given, and proposes a contrary point of view in which the only path to expertise is engaging in a lot of deliberate practice over a very long time. After laying these two foundational building blocks, the book turns to talking about the what mental representations are and how they interact with deliberate practice. The book finishes with a few additional practical tips on how to effectively engage in deliberate practice.

Part 1: What is Deliberate Practice?

Peak defines deliberate practice as an intense form of practice, designed to push ones self out of their comfort zone but in a safe and focused way. Deliberate practice should feel hard and is likely not very enjoyable. The authors compare deliberate practice of a mental ability to going to the gym — both deliberate practice and going to the gym are only actually effective at creating changes if they feel hard and uncomfortable. But while it is important for deliberate practice to feel hard, it should not be so hard as to result in physical injury; or in the context of a career, you should not push yourself so far out of your comfort zone that you risk getting laid off. You want to avoid major setbacks, while still constantly staying out of your comfort zone. By staying out of your comfort zone, you will move the boundary of what you can actually achieve. This will mean you continuously will have a new front upon which you need to push to actually stay outside of your comfort zone.

Deliberate practice is also highly intentional and practical. When engaging in deliberate practice there should be a specific goal in mind with a plan to achieve that goal. The goal should be oriented towards being able to do a specific skill that you cannot do today. This implies two types of goals that should NOT be used for deliberate practice. First, deliberate practice should not aim at learning new content, but should instead focus on acquiring new skills. Learning comes along for the ride during deliberate practice for skill acquisition, and the learning is actually more sticky then if it was acquired outside of the context of acquiring a new skill. Second, deliberate practice should not aim at some end outcome like winning a championship or getting a certain rating at work. Those outcome based results will come naturally from improving your skill set through deliberate practice. So before engaging in deliberate practice, think about specific skills within your domain that you need to get good at. Then pick one of them and design a practice routine around improving at that specific skill. Doing this over and over for several sub-skills within your domain will ultimately sum up to general improvement within your domain.

The final note that the authors make as they are defining what deliberate practice is, is that after reaching a certain level of baseline acceptable performance in a domain, simply doing an activity won’t make you better at it. Personally, I see this to be obviously true in my own life. I use to engage in a lot of deliberate practice of chess and I got pretty good. But now, I just play for fun online. I play the same type of stuff over and over again and I never really get better. Just doing the activity does not make me better at it. This is because I am not pushing myself out of my comfort zone and expanding what I am able to do. The authors make an even stronger claim by saying that if you do not engage in deliberate practice, the default outcome is for your skills to slowly decline. They give an example of doctors in which doctors that have been practicing for 5 years out perform doctors that have been practicing for 25 years on several benchmarks. They attribute this result to the slow decline of skills of the doctors that have been practicing for 25 years without intentionally engaging in deliberate practice. The way I have internalized this idea for myself, is to remind myself that if I am not improving, I am likely regressing.

Up until this point, the book has focused on defining what deliberate practice is. In summary deliberate practice has the following attributes

Intense: Deliberate practice should feel hard and should push you to the edge of your mental and/or physical abilities in a safe and focused way.
Focused on Doing Skills: Deliberate practice focuses on being able to do a new skill that you cannot do today. It does not focus on end outcomes or learning — those things come along for the ride when acquiring new skills.
Goal in Mind: Deliberate practice should have a specific goal in mind, a plan to achieve it and a way to know if you are making progress.
Feedback: Deliberate practice requires getting feedback on your performance so you know if you are doing something correctly.
Just Doing Something More Doesn’t Count: Just doing a skill you already know how to do is not deliberate practice. If that is all you do, then over the long haul your skills will gradually decay.

Part 2: Adaptability of the Human Brain

Next, the authors turn towards debunking the commonly held belief that truly exceptional people are the result of some innate traits that there were blessed with. In order to debunk this belief, the authors conducted studies and interviews of truly exceptional people to see what sets them apart. The most detailed study cited in the book was a study of violin students in some famous music school. The researches divided the students into three groups — the good, the great and the truly exceptional. They then interviewed each of the groups to try to understand what was the same between them and what was different. They found that all the groups agreed that intentional, solitary, intense practice was the most important factor for getting better. All the groups also agreed that this type of practice was hard and generally not very fun. The only attribute the researches could find that separated the groups from each other was the total amount of deliberate practice that they had engaged in over their lifetimes — the truly expert group simply had logged more total hours of deliberate practice then the other groups. In short, the thing that made the experts unique was not some innate trait that would have been impossible to replicate, but simply engaging in more hard, deliberate practice.

The authors continue to press their case that expertise comes from deliberate practice and not from innate abilities by citing the famous study of the London Taxi Cab Drivers. Basically, this study did scans of London Taxi Cab drivers’ brains and showed that the brain had physically changed in response to learning about the streets of London. The researches demonstrated a causal link between the changes in the brain and the practice by also scanning the brains of retired drivers — showing that the changes that had occurred during their active deliberate practice, had regressed in retirement. The generalizable principle from this study is that the brain is highly adaptable — it will actually change in response to deliberate practice. These changes include rewiring and in some case can include the development of new neurons. Additionally, the researches cited examples that demonstrated that the adaptability of the brain continues well into adulthood. While it is true that children's brains are more adaptable, the adult brain is still very adaptable.

The authors do not totally dismiss the importance of innate traits, but they reframe their importance from being a direct source of expertise to an being input factor to the total amount of deliberate practice that is engaged in. For example, rather than attributing someones amazing math abilities to some innate, exceptional math gene, the authors would instead argue that that person likely had early childhood exposure and genetic traits which made them more likely to engage in more practice of math then their peers. In order to back this claim up, the authors cite another famous study of the Polgar sisters. The Polgar sisters were very intentionally exposed to chess at an early age from their father and mother and given all the opportunity in the world to get good at it. Neither of the parents was exceptionally talented at chess, so it was unlikely the sisters had some innate chess gene. In the end all three sisters ended up being truly excellent chess players, pushing the limits of what female chess players had ever accomplished.

In summary, this section of the book addressed the adaptability of the human brain. It made the following main points -

Its Practice Not Innate Traits: The thing that makes experts unique is not some innate trait that the person was blessed with but rather that they simply engaged in more deliberate practice then their peers.
Traits Can Enable Practice: The authors do not totally dismiss the role of innate traits, but treat them much more as an input factor that influences how much deliberate practice someone will engage in rather than the actual driver of excellence.
The Brain is Adaptable: The authors point out a few examples the demonstrate the adaptability of the brain. They claim that the brain physically changes in structure in response to deliberate practice over a long period of time.
Adaptability into Old Age: While a child’s brain is special, and there are changes that can only occur at a young age, the human brain remains highly adaptable even into old age.

To conclude this section, I will mention one metaphor that the authors gave from the book that really stuck with me. They compared the human brain to a computer, saying that when we engage in deliberate practice of some skill we are not just uploading new software onto a computer with a fixed amount of RAM and CPU, but instead we are actually upgrading the hardware. In this way, engaging in deliberate practice does not just enable us to fulfill our potential, but it actually enables us to grow our potential.

Part 3: Mental Representations

After defining what deliberate practice is and making a case that deliberate practice over innate ability is the path to expertise, the book introduces mental representations and how they interact with deliberate practice. The authors define a mental representation as any structure stored in long term memory that enables processing large complex patterns quickly and effectively. In order to demonstrate what they meant by mental representations, the authors use chess players’ amazing ability to see a position only for a moment and remember where all the pieces are. What is happening in the brain of these chess masters when they do this is not that they store all the piece positions in short term (working memory), but instead that they see the board as a single whole in which the pieces relate to each other in ways they have seen many times before. These piece relationships are part of the chess players’ mental representation for thinking about the board. So when the player sees the board, they don’t need to try to store all the pieces in working memory, instead they just identify the parts of their mental representation (which is stored in long term memory) that is applicable to the current position. In this way the chess master has bypassed the limitations of working memory. Generalizing from this example, we see that mental representations offer two benefits. The first is they enable improved memory about a domain and secondly they enable processing large amounts of information quickly.

The authors then connect mental representations to deliberate practice by claiming the primary purpose of deliberate practice is to develop ever more detailed and effective mental representations. They argue the thing that makes experts really unique is the quality and detail of their mental representations for the domain in which they are an expert, and that the ONLY way to create expert level mental representations is to engage in a lot of deliberate practice over a long period of time. Additionally, the authors note that the relationship between deliberate practice and mental representations creates a virtuous cycle in which deliberate practice improves the quality of mental representations, and better mental representations enable a higher quality of deliberate practice. The reason better mental representations lead to better deliberate practice is because mental representations enable self-correction. Without a well defined mental representation, its hard to know if you got something right, or went about it in the best way. But the more expert you get, and the better your mental representations are, the more you will just develop of a sense when you are doing something correctly.

In summary, this section defined mental representations as a structure stored in long term memory that enables effective processing of large complex patterns within a specific domain. These mental representations improve memory, processing speed and learning ability within the domain.

Personal Reflections

Like most self help books, I found this book to provide an interesting idea but it could have been 90% shorter. In order to remember the learnings from this book I took some time to reflect on how I could apply it to my own life. I group these applications into two categories — tactical and mental. The tactical action items are things I can concretely do in order to incorporate the learnings of this book. The mental action items are things I should remind myself.

Tactical Action Items

Mentorship: Setup bi-weekly mentorship 1:1s with two engineers that I respect and want to learn from. The purpose of these 1:1s should be to learn more about how these engineers approach problems and to learn what skills they have that I am still missing. In order to achieve this I will work with them to plan out projects I can take on that will push my abilities and I will talk through problems with them that I am currently struggling on. The goal of these mentorship sessions is to take concrete action items that I can incorporate into my job as part of my deliberate practice.
Planning: Within a company there is already a natural cycle of yearly and quarterly planning. I am going to take these natural points as a time for my own reflection/planning of my career. I will keep a document in which I define what my goals are for the year and break down steps to acquire the skills to achieve those goals on a quarterly and monthly basis. I will share this document with my manager and do performance syncs with my manager. This will act as both an accountability mechanism and will layout an intentional plan for deliberate practice.
Morning Practice: I have already built in a morning learning block into my calendar and I have historically been decent at sticking to it. I have decided to reframe this time from “learning” time to “practice” time. While this does not seem like a meaningful change, the name change is intended to remind myself that I should be focused on engaging in deliberate practice aimed at acquiring new skills. Learning is the side effect of new skill acquisition rather than the primary focus.
Physical Todo Cards: Recently I have started using physical todo cards to manage my tasks rather than digital task lists. I have really enjoyed using these physical todo cards so far. One nice benefit of using these physical cards is that they have a backside that makes for a natural place for reflection. I just need to keep cards for daily, weekly, monthly, quarterly and yearly tasks. Then I can write notes on the backside of the card at the end of these periods to reflect on how things went. I can reflect on the things that went well that I want to continue to do, and I can reflect on the things that did not go so well that I should consider changing.

Mental Action Items

Growth Mentality: I find it so tempting to slip into the trap of thinking that I have hit some ceiling to my ability and just wishing that I had the innate abilities that others seem to have. I need to continuously remind myself that potential is expandable and the way to become an expert at something is through putting in a lot of hours of intense deliberate practice.
Health: Through several recent books on productivity, time management and now on expertise, a theme that keeps coming back up is the importance of health. Specifically, both exercise and sleep are really empathized as critical pieces to peak productivity and learning. While I don’t really like exercising or having good sleeping habits, I really do like pushing myself to the peak of my abilities. So reframing sleep and exercise from being a tax on my time, to being a critical part of peak performance is a really powerful reframing for me. My hope is that when I am tired and not wanting to go to the gym, the thing that will get me off my chair and into the gym is my desire to perform at the top of my ability in my field.