Trunk Strength Grinds: The Durability (Anti) Secret

If you’ve followed my training for any length of time, you know I’m big on durability. The ability to stay in the game, train hard, and keep injuries at bay is one thing that separates those who perform for a lifetime from those who burn out too soon.

Even more importantly (for me), is the ability to handle anything that life outside of the gym throws at me without "throwing out my back," "slipping a disc," hurting a shoulder or knee... you get the idea.

Moving furniture? No biggie.

Yard work? Easy... and actually quite enjoyable.

Throwing the ball for the dogs 100x, hikes, bike rides, stacking wood.... wrestling and playing with my 10 yr old nephew? I'll smoke his ass!

And being the one that friends and family call for help with anything physical? That's me.

I give most of the credit for this level of durability to these Trunk Strength Grinds.

Let’s clear one thing up first—I didn’t invent these grinds. I believe they originated with MTI (Mountain Tactical Institute). The head coach there opened a gym in Charleston (where I had just moved to at the time), and by pure luck, I stumbled upon it because I desperately needed a place to train.

First, I trained there. Then I coached classes. Then I ran the show while the boss was off at the fire academy. Eventually, I bought the gym and took over completely...

These grinds were part of the programming from the start, and I adopted them, adding my own twists along the way.

What Are Trunk Strength Grinds?

Trunk Strength Grinds are a form of structured, aerobic paced, movement focused strength and conditioning work designed to reinforce trunk integrity and reduce the risk of injury.

Each grind lasts 10 to 30 minutes and includes 3 to 6 movements cycled through continuously. The goal is not max effort but steady, controlled work that challenges your body in multiple planes of motion.

And keep in mind: the trunk is anything from the nipples to the knees and everything in between.

How Often Do You Train Them?

How often you do these grinds is goal and cycle dependent. Some cycles, we will do this once per week just as a maintenance piece. Other times, it's a bigger focus and we may have 2-3 of these circuits per week.

There are a few places they fit nicely in a microcycle:

• After the main lifts of a strength session as accessory work
• Prior to any type of training session as a warmup for 5-15 minutes
• After a hard and grueling work capacity session of any duration

I suppose if you wanted to do an entire cycle focused on trunk strength building, you could certainly do that, too.

Why These Grinds Are a Game Changer

I firmly believe these grinds have been the key to keeping me damn near injury free for the past 7-8 years (knock on wood). Sure, I’ve had the occasional nagging issue—that’s part of training hard and training often. But nothing major, nothing debilitating. These grinds help reinforce my structure and keep everything functioning smoothly.

 

 

 

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The Key to Trunk Strength Grinds: Aerobic Pace + A Lot Of Reps

Like I mentioned before, these aren’t metcons or high intensity burners. Trunk Strength Grinds are done at an aerobic pace—your average heart rate during the grind should be at your aerobic HR zone (use 180 minus your age as a guide). For most people, that’s around 150 bpm or less.

So in one session, you’re hitting:

✅ Aerobic work
✅ Hypertrophy
✅ Trunk integrity
✅ Injury reduction
✅ Mental resilience

The Movement Patterns We Train

These grinds are built around fundamental movement patterns that reinforce total body stability and strength:

• Squat patterns

• Hinge patterns (deadlifts, kettlebell swings, glute bridges, etc.)

• Lunge patterns (forward, reverse, lateral)

• Trunk rotation

• Loaded carries (farmers, single-arm, overhead, bear hug, etc.)

• Trunk anti-rotation (planks, Pallof presses, etc.)

• Mobility work (hip, spine, knees, ankles, shoulders)

See why I call it durability training?

Sample Trunk Strength Grinds 

15 Minute Grind

• 20/20 sec. Standing Founder

• 3x each side Turkish Get Up @ 15/25 lbs

• 8x Sandbag Clean + Press

20 Minute Grind

• 8x Kang Squats @ 45/65 lbs

• 12x Kneeling Halfmoon w/ 25/35# plate

• 15/15 sec. Side Planks

• 45 sec. Heavy Bear Hug Carry

15 Minute Grind

• 10x Lateral Ball Slams (5 each way)

• 20/20 sec. Standing Founder

• 10x Sandbag Ground to Shoulder

• 45 sec. Plank

15 Minute Grind

• 5x each side Windmill @ 15/25 lbs

• 12x Slasher to Halo (6 each way) @ 25/35 lbs

• 10/10x Single Leg Deadlift

• 45 sec. Farmers Walk

Trunk Strength Grinds are simple but brutally effective. They build strength, control, resilience, and work capacity—all without destroying your body. If you train hard and want to stay in the game for the long haul, incorporating these into your routine is a non-negotiable.

Now, go set a timer, pick a grind, and get to work.