He nails it solidly. This is how I designed my training program. Anyone that's been in it knows ;)
How Experts Practice Better Than the Rest
by James Clear | Read this article on JamesClear.com
My dad and I were standing in the front yard. Maybe that’s why I remember it. We typically practiced baseball in the backyard, but for some reason we were out front that day. I was around 9 years old and learning how to pitch. My dad was walking me through the basic mechanics.
On this particular day, we were working on the backswing of my arm. The ball came out of the pocket of my glove, my elbow went up, and my arm began to swing back behind me in preparation to throw.
“Elbow up.” That was the cue. “Elbow up. Elbow up. Elbow up.”
We spent that whole session focused on one little movement of 12 inches or so when my hands parted and the backswing started. We probably repeated it hundreds of times that day. Sometimes with full throws, but mostly with drills and little practice patterns.
We kept working on this for a few days and then, at some point, we stopped talking about getting my elbow up and moved on to the next phase of the pitching motion. It wasn’t until weeks later, when I realized we hadn’t said “Elbow up” in awhile, that I noticed that I was getting into the right position automatically.
I didn’t know it at the time, but this was one of my first exposures to the concept of deliberate practice.
What Do Experts Do For 10,000 Hours?
Malcolm Gladwell published his blockbuster book, Outliers, in 2008 and the most talked about idea from the text was the 10,000 Hour Rule. Gladwell, citing research by K. Anders Ericsson, explained that the key to becoming world-class in any field was to practice a specific task for at least 10,000 hours.
As you might expect, people quickly latched onto the number 10,000 and forgot the details of the argument.
Obviously, there is no magic in the 10,000th hour, but it is true that you need to put in a lot of work to become world-class in any task. However, the important question is this, “What should that work look like? If you want to become great at your craft, what exactly should you with your 10,000 hours?”
You can’t simply put in your time and log 10,000 hours. You have to practice deliberately on a specific skill.
But what does that mean? What, exactly, does deliberate practice look like?
What is Deliberate Practice?
During a 2012 talk, programmer and author Kathy Sierra explained deliberate practice in a very simple and elegant answer. 
Deliberate practice is when you work on a skill that requires 1 to 3 practice sessions to master. If it takes longer than that, then you are working on something that is too complex.
Once you master this tiny behavior, you can move on to practicing the next small task that will take 1 to 3 sessions to master. Repeat this process for 10,000 hours. That is deliberate practice.
This is the first practical definition of deliberate practice that I have come across. It’s the first time I have seen the 10,000 Hour Rule broken down into something tangible that you can use at your next practice session or the next time you show up to work. And it also ties in quite nicely with the idea of getting 1 percent better each day. Each practice session should be focused on mastering a tiny skill that makes you slightly better at our craft.
The Idea in Practice
This basic method of deliberate practice applies to nearly any behavior, but let’s use weightlifting as an example.
This is what deliberate practice might look like if you are trying to learn the clean and jerk…
During the first session, you learn how to grip the bar properly and the fundamentals of the hook grip. There might be an additional session where you learn how to properly apply chalk to your hands before a lift.
Once you learn how to grip the bar, the next session is focused on teaching you the basic movement with a broom stick in your hand. At this point, you are simply learning the primary phases of the lift.
After a few sessions with the broom, you learn how to set the starting position of your feet. You experiment with different variations and get feedback over and over again on your foot position.
Next, you learn how to get into the set position to begin the lift. Perhaps you spend a few sessions focusing on different aspects of this set position. For example, you might spend one day working on keeping your shoulders back and your scapula down as you prepare to lift off the floor. Or, you could spend another session learning how to take the slack out of the bar before beginning the lift.
After that, you move on to actually lifting the bar off the floor (known as the “first pull”).
And so on…
Notice that during each practice session focused on one individual skill. Your energy and effort were directed toward something small enough that you could master it (or at least master the basics of it) within 1 to 3 sessions.
Also notice, however, that each skill built upon the one before it. The knowledge that you built in early sessions, like learning how to grip the bar or how to set your feet properly, was required for succeeding in later sessions as well. (This is why good teachers make such a big deal about the fundamentals. Get them right and they help you every time you go to work. Get them wrong and every task suffers because of it.)
This is what deliberate practice looks like. I like the 10,000 Hour Rule because it is a reminder that you have to put in your reps. But it’s not as simple as working for a long time. It has to be vigilant work. And in many ways, you have to be continually obsessed with building upon your current skill set in small ways.
3 Questions for More Deliberate Practice
From what I can tell, the experts who embrace the idea of deliberate practice continually ask themselves three questions…
1. Do I understand the fundamentals? No matter how advanced they become, experts never lose sight of the fundamentals. In many ways, they are advanced for that very reason: they understand the fundamentals better than anyone else.
2. Am I working on the next step? There are a lot of smart people who know what the next step is, but never do it. Similarly, there are many people who take action, but waste time working on skills that don’t build upon each other. Experts build knowledge and skills that are cumulative.
3. What am I missing? One of the greatest pitfalls of the 10,000 Hour Rule is that it makes expertise seems like a finish line that can be crossed. It can’t. Expertise is not a race that can be won, it is simply a process that can be embraced. Experts are constantly asking themselves, “What am I missing? What new information is out there? What can I learn? How can I grow?”
Expertise is a process, not an outcome. “Elbow up.”