Tuesday, October 17, 2017

This is why you need to move perfectly before you add weight


Last week I was listening to Randy teach a new lifter how to snatch. One thing he said was "Every lift goes into the bank; if you do a bad one you need to do good ones to make up for it" (or something like that, Randy's more eloquent than I am).  The basic idea is that you don't want your brain to learn how to do something wrong because it will be more work to undo it later - especially once you get to the point of "muscle memory" (Side rant from Amy, the brain doctor: Don't say "muscle memory"! There is no memory in your actual muscles; it's spinal cord and cerebellar programming plus slow cortical learning, which results in automatic coordination without obvious awareness.)

It's the same reason that I make everyone in my class do 3-5 perfect light reps when you miss a PR attempt. I don't want the last thing your brain remembers to be how to not lift the weight. And it's why I always make fun of the CrossFit "Grace" and "Isabel" workouts (That's 30 C&J for time at 135lbs and 30 Snatches for time at 135lbs, respectively). Olympic weightlifting shouldn't be done for time.

Can we quantify how bad a bad rep is for you? Maybe.

I found a really cool paper last week written by a computational linguist. He was studying how children learn to count and when they switch from memorization to pattern making (I care about this stuff because of my side-work in machine learning). If you think about it, learning "one", "two", "three", "four", "five", "six", "seven", "eight", "nine", "ten", "eleven", "twelve" is completely arbitrary. There's nothing encoded in the language that maps to the actual concepts of those numbers.  When you get to "thirteen" (almost three-teen), "fourteen", ... you can start to grasp a pattern. How quickly a child learns to count is a function of how many "exceptions" to the rule they run into. In English, once a child gets to about seventy, they have seen enough of the pattern to overcome the exceptions, and being able to count to seventy means that they can go on forever. (In Chinese languages, it's about 40 since their language is more regular, and it's longer in less regular languages - there's a whole bunch of literature on this.)

It appears that the learning research has a well-established model across many domains that if there's a rule with exceptions, you have to see n examples where n/ln n is greater than the number of exceptions to grasp the rule. Huh?

In our language example, the first exceptions to our counting rule are "one", "two", ..., "thirteen", "fifteen", "twenty", "thirty", "fifty" - 17 of them.  And 73/ln 73 is greater than 17 - and that's what they see, once you get to 73, you've learned enough to override the 17 exceptions.  That is, you need to know 56 correct examples to undo the 17 bad examples.

Since this shows up across all kinds of learning domains, I wonder what it's like in learning a movement, like the snatch or clean and jerk, which are very dependent on motor patterns. Or even something simple like a squat or deadlift? I don't know, but I imagine that there's going to be some overlap. Just like learning to count, it's your brain learning how to do something over time and with practice.

So if you do one bad rep, how many good reps to you need to undo it? One. But if you do 10 bad reps, how many good reps do you need? 26! What happens when you try to set a new sub-2:00 Grace time? According to this model, you need 121 good reps to undo those 30 crap ones.

Bad Reps  Additional Good Reps Needed To Undo The Bad Reps
 1           1
 2           2
 3           2
 5           8
 8          19
10          26
15          47
20          70
30         121

Moral of the story? Make your practice count.



Warm-up

row 500 / run 400
crawling lunge
10 KB swings or snatches
double KB overhead lunge
10 TGUs or windmills
10 goblet squats
5 pull-ups or push-ups or dips

Strength

snatch 5-3-2-3x2

Accessory/Skill

2 windmills between strength sets

Group Workout

Climb to a new KB overhead squat max

then 

5 rounds:
2L, 2R KB overhead squat one interval down from above
20 KB swings @ a moderate weight

then 

goblet squat ladder:
25-20-15-10-5
Increase weight each set.  
Work up to as heavy as possible

then

2 minute bar hang



Subscribe


Sign up for classes


Strength Metrics


Get Xero Shoes