Cutting Biomechanics: How pressures, pelvic position, and performance are related
Note: This post has a free quiz below!

Impromptu IFASTU. Let’s talk about the bootydo [30:30].

This was a fun one. Bill and I got to talking the other day about cutting mechanics and pressure moderation in the body. If you want to understand movement, you need to understand how humans manage air.

This post is more advanced. If you find yourself getting lost, you may want to watch Brandon’s intro to biomechanics.

Part 1 — Discussion

  • Video of one of our athletes so we have some context for this conversation. [0:00]
  • Two things I notice a lot in cutting (and other things) [04:19]
  • The ideal position to be in after a cut (you’ve heard of it before) [4:44]
  • How the trunk should orient in a directional step (like when stealing a base)
  • Bill’s self-proclaimed limbo ability [5:36]
  • How trunk rotation affects force application to the ground (defining it in layman’s terms) [5:51]
  • The first thing you need to understand [7:50]
  • Why we don’t need to talk about autonomics and threat AT ALL right now (outside of understanding that it’s the undercurrent of everything) [8:15]
  • How squatting with your butt up is the same thing as failing to change levels in multidirectional speed activities [9:06]
  • The different in appearance of areas of low pressure vs areas of high pressure [10:00]
  • The simple explanation of air movement and pressure (what prevents air from going up into the apical lung?) [10:34]
  • Where people with narrow infrasternal rib cage angles like to hold pressure (and why they’ll suffocate if they find abdominal tone) [11:05]
  • Why your clients need to orient their hips if they’re going to move quickly in any multidirectional activity (especially true for your intramural athletes with day jobs) [11:43]
  • The difference between a directional step and a walking step (look at the forces! [11:53]
  • Why glute max is actually NOT propelling your forward much at all in multidirectional movement (and what it’s REALLY doing) [12:37]
  • Why I like to cue people to drive off the front leg in their directional steps (I know that they actually need to drive off of both at the right time) [13:22]
  • How pressures shift in a directional step when starting in athletic stance (take the quiz to test your knowledge) [13:45]
  • What the abs are doing in all this (because abs are usually a good thing, right?) [15:03]
  • A specific example of pressure transferring (let’s take it step by step… no pun intended) [18:30]
  • What the pelvic floor does when you adduct and internally rotate your hip [20:46]
  • What has to happen before quick movements can happen (remember your muscle contractions?) [21:09]
  • Why apical lung expansion is absolutely essential for orienting the trunk in a directional step (“snap that and reverse it”) [23:50]
  • What creates the negative pressure in the upper chest (welcome to IFAST Raw) [25:26]
  • The role of all those weird grunting noises people make when they exert themselves (in both exercise and in the bathroom) [27:59]
  • How Olympic weightlifters use this mechanism to make sure there isn’t too much or too little pressure before their jerk (this porridge is juuuuust right) [28:43]
  • How Rufus remembers former IFAST intern Liz Messina (can she squat?) [29:23]
  • How someone lowers their center of gravity when they can’t posteriorly rotate their ilium (like those people feel like they’re squatting really deep but they never actually hit depth) [30:12]
  • What ultimately determines how you move [32:28]
  • When grunts are appropriate (and inappropriate) [33:09]
  • How grunts are related to landslappers (and what they mean to your coaching) [33:56]
  • The rabbit hole question (you should NOT start at this timestamp) [34:50]
  • The balance of business; I admit that there are at least 3 kids I feel I am totally failing (and what to say when your clients tell you, “I don’t want to do any of these goofball exercises”) [37:05]
  • A “hip separation, hop skip” progression walkthrough (making a Minimum Viable Product for coaching a client) [39:45]
  • Bill calls BS on “posture doesn’t matter” (what do you think?) [40:16]
  • How the soleus extends the knee (one of Bill’s favorite questions) [43:07]
  • RNT for the abs (this is mostly a joke) [44:02]
  • Here’s the lunge video I reference at the end (but Bill says some of it is wrong… what do you think?) [45:50]


Want more practice? Quiz yourself!

Click here to take the quiz


Like I said: this was a fun one.

What did we forget? Leave a comment below and let’s discuss.

Part 2 – Interns Talk Cutting

You are what you repeatedly do.

An extension of “Pressure and Cutting” with Bill and me. The interns ask questions about:

  • Plyo step – definition, what it’s for, and the drive step afterwards
  • Ground reaction forces – athletic positions, dynamic movement, and how internal and external pieces form the movements you want.
  • The mechanics behind a turn – where does the foot go, where do the forces go, where does the pressure go, how does the body orient itself
  • Crossover steps and directional steps – the wording, what the upper and lower body do, and what happens when you can’t do it


Have more questions to ask? Leave a comment below and let’s discuss.

Oh, and did you take the quiz?

Related Posts

Published by Ty Terrell

Let's have a discussion

This site uses Akismet to reduce spam. Learn how your comment data is processed.