JM Press: Bench Press Lockout Tricep Specialist Builder

Among powerlifters who stall in the upper portion of their bench press, tricep lockout weakness is the most common limiting factor—accounting for failures at approximately 90-95% of ROM in roughly 70% of missed competition attempts. The JM Press, developed in the 1990s by Westside Barbell competitor JM Blakley, was specifically engineered to target this sticking point by combining the elbow flexion depth of a skull crusher with the pressing mechanics of a close-grip bench press.

Unlike standard tricep extensions that place maximum tension at the stretched position (near the ears), the JM Press loads the long head of the triceps most heavily through the mid-range and extension phase—precisely where lockout breakdowns occur. This article covers the biomechanical rationale, precise technique cues, evidence-informed loading zones, and how PoinT GO velocity data can optimize your JM Press programming. Related: ankle dorsiflexion test

Origin and Purpose

JM Blakley was a Westside Barbell lifter who competed at a world-class level in the 1990s and is credited with systematically cataloguing Westside accessory exercises for general application. The JM Press emerged from his observation that neither close-grip bench press nor skull crushers in isolation adequately address the specific torque demands that the triceps must handle during competitive bench press lockout—particularly under the extreme loading seen in equipped powerlifting, where the shirt releases energy rapidly between 4-8 inches from lockout.

In raw lifting, lockout weakness manifests when the bar slows dramatically 2-4 inches from full extension. Electromyographic studies (Barnett et al., 1995) confirm the lateral and medial heads of the triceps are most active during elbow extension from 90° to full extension—the exact ROM the JM Press stresses. The exercise thus provides a stimulus that is mechanically specific to the lockout failure pattern in a way that neither compound bench pressing nor isolation extensions achieve in isolation.

Tricep Anatomy and Lockout Mechanics

The triceps brachii has three heads with distinct moment arms across elbow joint angles:

• Long head (caput longum): Crosses the shoulder joint; maximally active during mid-range elbow extension when the shoulder is in slight flexion. The JM Press' descent path—bar traveling toward the lower neck/upper chest rather than the forehead—keeps the shoulder slightly flexed and maximizes long-head contribution.
• Lateral head: Most active during the final ~30° of elbow extension. The stiff-arm lockout demand of the JM Press, where intentional deceleration is avoided (unlike skull crushers where lifters typically slow the bar to protect elbows), ensures maximal lateral head recruitment.
• Medial head: Active throughout the ROM; acts as a tonic stabilizer. Benefits from the sustained time-under-tension created by the controlled descent in the JM Press.

The key mechanical insight is that during a bench press lockout at 90-95% 1RM, the elbow extensor moment demand peaks because the bar velocity is lowest—the lifter cannot rely on stored elastic energy—yet must produce maximum force to complete the lift. The JM Press replicates this specific torque demand far more closely than any standard accessory movement.

JM Press Technique Step-by-Step

Setup

1. Lie on the bench with standard bench press setup: shoulder blades retracted and depressed, feet flat on the floor, slight lumbar arch.
2. Take a close grip—thumbs 12-16 inches apart (slightly narrower than competition bench grip). Wrap thumbs around the bar for safety; an open or 'suicide' grip dramatically increases injury risk on this movement.
3. Unrack and position the bar over the lower sternum/upper chest with elbows tucked approximately 30-45° from the torso (not flared like a wide-grip bench, not pinned like a close-grip bench).

Descent Phase

1. Initiate descent by allowing the elbows to travel forward and downward simultaneously—this is the defining characteristic of the JM Press. Elbows should move toward a position roughly over the lower chest/upper abdomen.
2. The bar descends at an angle, moving slightly toward the face rather than straight down. Think of a diagonal path: the end position has the bar roughly at forehead height but with the elbows positioned below sternum level—a position that is difficult to describe but immediately intuitive when felt correctly.
3. Descent depth: until the bar is 2-4 inches from the throat/lower face. Do NOT let the bar touch. This partial ROM targets the specific range where lockout strength is required.
4. Maintain continuous tension—do not relax the triceps at the bottom. The JM Press is not a stretch exercise; it is a strength exercise for the mid-to-end range of elbow extension.

Press Phase

1. Drive the bar back toward the starting position by extending the elbows with maximal intent. The elbows and bar should travel simultaneously—do not extend the elbows first and then press, which would convert it into a skull crusher.
2. Maintain wrist stacking over the elbows throughout. Wrist collapse (excessive extension) transfers load from the triceps to the forearm flexors and increases wrist injury risk.
3. Finish with elbows not fully locked to maintain triceps tension, or with a brief full lockout depending on training goal (partial pause at lockout is recommended when training the lockout specifically).

Loading Parameters and Velocity Zones

Because the JM Press is an accessory movement—not a competition lift—it should be loaded to produce specific adaptations rather than maximal loads. Typical loading ranges from 40-65% of competition bench press 1RM:

MCV on the JM Press is inherently lower than on competition bench press at equivalent relative intensities because of the unusual bar path and the reduced stretch-shortening cycle contribution. Tracking MCV with PoinT GO allows you to distinguish genuine strength gains (upward shift of the load-velocity curve) from mere technical improvement within a given session.

A useful rule of thumb from Westside practitioners: when JM Press strength (using the lockout-specific protocol) reaches approximately 55-60% of competition bench 1RM for 5×5, lockout weakness is typically no longer the primary limiting factor, and the lifter should shift emphasis to other sticking points.

Programming the JM Press

The JM Press is most effective when placed as a direct accessory after main bench press work—while central nervous system fatigue is present but technique degradation is not yet severe. It should not replace close-grip bench pressing entirely, as the JM Press' partial ROM limits load accumulation for general upper-body pressing volume.

Weekly Placement

4-Week JM Press Mesocycle (Strength-Focused)

• Week 1: 4×6 at ~55% bench 1RM; establish baseline MCV for the load
• Week 2: 5×5 at 57.5%; verify MCV is maintained or improved vs. week 1
• Week 3: 5×4 at 60%; target lockout pause (1-2 sec) on every rep
• Week 4 (deload): 3×5 at 52.5%; focus on technique quality, no MCV targets

Common Errors and Corrections

• Error: Elbow flare on descent. Correction: Keep elbows tracking forward—not out to the sides. Elbow flare converts the movement into a modified bench press, eliminating the specific mechanical demand on the medial and long heads.
• Error: Bar descending straight down (skull crusher path). Correction: The bar must travel toward the throat/clavicle area with elbows moving simultaneously downward and forward. Practice with a very light load until the diagonal path feels natural.
• Error: Bouncing the bar at the bottom. Correction: The JM Press has no rebound point—there is no anatomical contact and no stretch-reflex contribution by design. Any bounce represents loss of muscular tension. Pause briefly or deliberately decelerate in the bottom 2 inches.
• Error: Using the same grip as skull crushers (very close). Correction: A 12-16 inch grip (shoulder-width or slightly inside) is optimal. Very close grips increase wrist torque and reduce the mechanical specificity to bench press patterns.
• Error: Excessive wrist extension. Correction: Wrists should be neutral or in very slight extension. Cue: 'keep your knuckles pointing toward the ceiling throughout the movement.'

Variations and Progressions

• Swiss bar JM Press: The neutral or angled grip of a Swiss bar reduces wrist and elbow stress while preserving the movement pattern. Excellent for lifters with chronic elbow tendinopathy who cannot tolerate a pronated grip under load. Expect MCV to be 0.05-0.10 m/s higher at equivalent loads due to improved mechanical leverage.
• Dumbbell JM Press: Each arm works independently; useful for identifying and correcting asymmetries. PoinT GO's bilateral comparison can quantify inter-limb velocity discrepancies that would go unnoticed with a barbell.
• Banded JM Press: Attaching resistance bands to the bar creates accommodating resistance—the load increases precisely in the ROM where the triceps are strongest (the lockout), more closely matching the natural strength curve. Effective for advanced lifters who have plateaued on straight-weight JM pressing.
• Pause JM Press (2-second pause at lockout): Eliminates any residual stretch-shortening cycle contribution at lockout; develops isometric-to-concentric strength specifically. Most relevant for equipped bench pressers who must control the shirt's energy release through a hold position.