Landmine Floor One-Arm Chest Fly: Form, Sets & Tips (Unilateral Chest Fly)

Learn the Landmine Floor One-Arm Chest Fly for chest hypertrophy and anti-rotation control. Step-by-step form, sets by goal, common mistakes, FAQs, and recommended equipment.

Landmine Floor One-Arm Chest Fly: Form, Sets & Tips

Chest • Unilateral Fly

Landmine Floor One-Arm Chest Fly

Intermediate Landmine + Barbell Hypertrophy / Control

The Landmine Floor One-Arm Chest Fly is a unilateral chest isolation move that combines a fly pattern with the landmine’s natural arc path. Performing it on the floor helps limit excessive shoulder extension, while the single-arm load challenges your anti-rotation core stability. Think: wide arc down, then squeeze back toward the midline—without turning your torso.

This exercise is all about control. Keep a soft elbow bend, move slowly, and stop the descent where your shoulder still feels stable. You should feel the chest working—especially near the top as you bring the arm back toward the midline—without shoulder pinching or torso twisting.

Safety tip: Stop if you feel sharp shoulder pain, numbness/tingling, or pinching in the front of the shoulder. Use a smaller range, lighten the load, and keep the shoulder blade stable (don’t let it roll forward aggressively).

Quick Overview

Body Part	Chest
Primary Muscle	Pectoralis major (sternal fibers emphasis)
Secondary Muscle	Anterior deltoid, serratus anterior (stability), core/obliques (anti-rotation), rotator cuff (stabilization)
Equipment	Landmine attachment + barbell (optional: bumper plate, floor mat)
Difficulty	Intermediate (requires shoulder control + trunk stability)

Sets & Reps (By Goal)

Hypertrophy (main work): 3–4 sets × 8–12 reps/side (60–90 sec rest)
Controlled strength: 3–5 sets × 6–10 reps/side (90–120 sec rest)
Endurance / pump: 2–3 sets × 12–20 reps/side (45–75 sec rest)
Shoulder-friendly accessory: 2–3 sets × 10–15 reps/side (smooth tempo, stop shy of discomfort)

Progression rule: Add reps first (until you hit the top of the range), then add small load. Keep every rep smooth—no twisting, no bouncing, no “pressing” the weight up.

Setup / Starting Position

Set the landmine: Anchor the barbell securely in a landmine base (or a safe corner setup).
Body position: Lie on your back on the floor, slightly angled so the bar can travel in a comfortable arc.
Feet and hips: Bend knees, feet flat, and brace your core to resist rotation.
Grip and arm: Hold the sleeve/end of the bar with one hand. Start with the hand above the chest line.
Shoulder position: Keep shoulder blade gently set (down and back), chest “proud,” neck relaxed.
Elbow: Maintain a soft bend (about 10–30°). Do not lock out or let it collapse.

Tip: If your shoulder feels stressed at the bottom, adjust your body angle so the bar path is more diagonal and shorten the range.

Execution (Step-by-Step)

Brace and stack: Ribs down, core tight, shoulders relaxed. Keep your torso square to the ceiling.
Lower in an arc: Slowly guide the arm outward and slightly down, following the landmine’s natural path.
Control the bottom: Stop where you feel a chest stretch but the shoulder still feels stable (no pinching).
Squeeze back: Pull the arm back toward the midline by contracting the chest—keep the elbow bend consistent.
Finish balanced: End above the chest/shoulder line without overreaching or twisting the trunk.

Form checkpoint: This is a fly, not a press. If your elbow starts bending a lot or you’re “punching” the weight, lighten the load and re-focus on a wide arc + chest squeeze.

Pro Tips & Common Mistakes

Keep the elbow bend “frozen”: Changing the bend turns it into a press and shifts tension away from the chest.
Don’t twist your torso: Brace your core and keep both shoulders level—rotation reduces chest stimulus and stresses the spine.
Stop before shoulder discomfort: Floor helps, but your best range is where the shoulder stays centered and stable.
Move slowly: 2–3 seconds down, brief pause, 1–2 seconds up keeps tension where you want it.
Think “hug the tree”: Arc down and then “hug” back toward center with the chest.
Avoid shrugging: Keep traps quiet—shoulder blade stays controlled, not creeping up toward the ear.

FAQ

Where should I feel this exercise?

Mainly in the chest (pec major), with a noticeable stabilization demand in the core/obliques. You may feel some front-shoulder involvement, but it shouldn’t feel like a shoulder-only movement.

Is the floor version safer for the shoulders?

Often yes—because the floor limits how far your upper arm can drop. Still, your shoulder comfort depends on your angle, load, and control. Use a range where you feel a chest stretch without pinching.

How heavy should I go?

Start lighter than you think. If the elbow bend changes, the torso rotates, or you lose control at the bottom, it’s too heavy. A fly should feel smooth and controlled, not like a grind.

Can I do it on a bench instead of the floor?

Yes. A bench can increase range of motion, but it also increases shoulder extension demands. If you’re building tolerance, the floor is a great starting point.

How do I make it harder without adding much weight?

Slow the tempo, add a 1–2 second pause at the bottom, increase reps, or add an isometric squeeze near the top (where the chest is working hardest).

Recommended Equipment

Barbell Landmine Attachment — anchors the bar securely and gives the correct pivot arc
Landmine Handle (Single-Arm / Multi-Grip) — improves comfort and grip options for unilateral work
Olympic Barbell (2" sleeve) — standard bar for landmine setups (home gym staple)
Barbell Collar Clamps (2") — keeps plates secure and prevents shifting during the arc
Thick Exercise Mat — adds comfort for floor setups and helps you stay stable

Note: I’m linking to Amazon search results so you can choose the best option available in your region (brand, price, reviews).