The Lethal Gentlemen's Club

The Lethal Gentlemen's Club

Chapter 3: The Lethal Combine

Performance assessment guide inspired by the NFL Combine, Navy SEAL BUD/S Selection, and Delta Force screening protocols.

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Jack Krucial
Sep 13, 2025
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The NFL uses the combine to identify elite athletic talent from thousands of prospects. Navy SEALs use BUD/S to separate those who can operate under extreme stress from those who break. Delta Force employs selection criteria that filter the absolute best from an already elite pool of special operations candidates.

Each of these organisations has one thing in common: they cannot afford to get physical assessment wrong.

I have had direct conversations with GBRS groups DJ Shipley (former DEVGRU & SEAL Team 6 operative) when coming up with this testing battery:

Lives, careers, and millions of dollars depend on accurately measuring human performance under pressure.

We have adapted these combines into proven assessment protocol for high-performing businessmen & coined it The Lethal Combine.

The Purpose: Measuring The Lethal Standards

The Lethal Standards provide the framework for what complete physical capability looks like across four domains. But standards without measurement are useless.

The Lethal Combine is how you actually assess where you stand against those benchmarks. This testing battery transforms the theoretical standards into concrete, measurable data that reveals your current capabilities and identifies areas requiring focused development.

Without systematic testing, you're guessing about your progress. You might feel stronger or think your endurance has improved, but feelings aren't data. The combine provides objective measurement of your performance across all four critical domains: raw strength, elite gas tank, explosive power, and physique development.


When It's Applied: Quarterly Business Cycles

I run The Lethal Combine during the first week of each business quarter with each of my clients. Four times per year, aligned with your business planning cycles.

This quarterly timing serves multiple strategic purposes:

Training Effectiveness Tracking: After 12 weeks of training, you need to know if your approach is working. The testing reveals whether your strength is progressing, your cardiovascular capacity is improving, and your explosive power is developing as intended.

Training Load Calibration: The results directly inform your training percentages and loads for the upcoming quarter. Your 3-rep max bench press determines your strength training percentages. Your sprint and jump results guide your explosive power development protocols.

Program Adjustments: The data reveals imbalances and weaknesses that weren't apparent during regular training. Maybe your strength is solid but your cardiovascular numbers are lagging, requiring more focus on Elite Gas Tank sessions.

Quarterly Business Integration: Just as you review financial metrics each quarter, your physical capabilities get the same analytical attention. Your body is a business asset that requires systematic performance review.

Long-term Tracking: Quarterly assessment creates a longitudinal data set that shows trends, progress patterns, and the effectiveness of different training approaches over time.


The Specific Tests and Rationale

RAW STRENGTH

In order to mitigate testing based injuries, we will primarily utilise a specific rep scheme to keep clients safe, but also give us a very accurate 1 rep max training value.
The way we do this is as follows…

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