Mini Study: Deadlift & Dead Hang “Maxmimal Squeeze Grip” Intervals Improve Dynometer-Assessed Max Grip Strength

By Emmett Shaul, MTI Strength & Conditioning Coach

BLUF

This Mini Study was initiated to support the Relative Hand Grip event in the Canadian Military CANSOFCOM Physical Fitness Screening Evaluation (PFSE) test, which uses a hand dynamometer to assess grip strength. Currently, the CANSOFCOM PFSE is the only tactical fitness assessment we’re aware of that includes and dynometer-assessed grip strength event, however in the past at least one US Air Force Special Tactics Assessment included a dynometer-assessed grip strength event.

The problem with a dynometer-assessed grip strength event in a high jeopardy military fitness assessment is there is no clear way for the athletes to train for it without the purchase of a dynometer. No gym has a bunch of dynometers laying around for athletes to use to prep and improve their fitness, and thus score, on this event.

The purpose of this mini study was to test the effectiveness of two different exercises which use common gym equipment to improve dynometer-assessed grip strength: Max Squeeze Dead Lifts and Maximal Squeeze Dead Hangs from a pull bar. In addition to these two events, we also tested the same protocol using an dynometer.

Over 3 weeks (9 training sessions) with 4 trained athletes, we compared three 10 x 10 second maximal crush grip protocols: barbell deadlift holds, pull-up bar dead hangs, and dynamometer squeezes. All three protocols increased max effort hand dynamometer scores, with an overall average improvement of about 15 lb (~11%). In this very small sample, the deadlift-hold and dead-hang protocols produced the largest average gains – even higher than the dynometer-specific intervals,, but all three methods were effective and can be used in any setting where improving max-effort grip strength is the goal, not just PFSE preparation.

STUDY DESIGN

• Duration: 3 weeks of training
• Frequency: 3 sessions per week (9 total sessions)
• Assessment: Max grip test on a hand dynamometer, right and left hands
  • Pre-test: Start of week 1
  • Post-test: Start of week 4
• Athletes: 4 trained MTI lab rats
• Outcome measure: Hand dynamometer score in pounds (lb), right and left hands

Session structure (all protocols)

• 10 rounds, every 60 seconds (EMOM)
• 10-second maximal crush grip on the assigned implement
• Rest for the remainder of the minute

Each athlete was assigned to one protocol and completed that same protocol for all 9 sessions.

TRAINING PROTOCOLS

Each protocol used the same EMOM structure, differing only by implement.

1. Deadlift Hold – Maximal Crush Grip (135 lb barbell)
   Athletes assigned to the deadlift protocol performed 10 rounds of a double-overhand deadlift hold at 135 lb. For each round, they stood up with the bar and applied a maximal squeeze grip (what we informally call an “over crush”) for 10 seconds, then set the bar down and rested for the remainder of the minute. Connor and Michael followed this protocol for all 9 sessions.
2. Dead Hang – Maximal Crush Grip (pull-up bar)
   For the dead-hang protocol, sessions were 10 rounds of a 10-second dead hang from a pull-up bar. During each hang, the athlete actively squeezed the bar as hard as possible for the full 10 seconds, then dropped and rested for the remainder of the minute. Cody followed this protocol for all 9 sessions.
3. Dynamometer – Maximal Crush Grip (direct practice)
   In the dynamometer protocol, the athlete completed 10 rounds of a 10-second max-effort squeeze on a hand dynamometer. Each hand was trained within the EMOM (for example, right hand on odd minutes, left hand on even minutes). For each effort, the athlete applied a maximal crush grip for 10 seconds, then rested for the remainder of the minute. Emmett followed this protocol for all 9 sessions.

RESULTS

Table 1. Individual and average grip scores by athlete (lbs)

Athlete	Protocol	Initial Right	Initial Left	Final Right	Final Left	Avg Initial (R+L)	Avg Final (R+L)	Change (lb)
Emmett	Dynamometer	138.2	137.4	146.4	145.2	137.8	145.8	+8.0
Connor	Deadlift	116.4	120.8	139.2	137.4	118.6	138.3	+19.7
Cody	Dead hang	141.6	132.4	160.4	145.6	137.0	153.0	+16.0
Michael	Deadlift	130.0	126.8	142.2	144.8	128.4	143.5	+15.1

Table 2. Results by protocol (both hands averaged)

Protocol	Athletes	Avg Initial (lb)	Avg Final (lb)	Avg Change (lb)
Dynamometer	Emmett	137.8	145.8	+8.0
Deadlift hold	Connor, Michael	123.5	140.9	+17.4
Dead hang	Cody	137.0	153.0	+16.0

Across all eight hands tested (4 athletes × 2 hands):

• Overall pre-study average: 130.5 lb
• Overall post-study average: 145.2 lb
• Average improvement: approximately +14.7 lb (~11%) over 3 weeks

DISCUSSION

All three crush grip protocols improved max effort hand dynamometer scores over just three weeks, and every athlete improved in both hands.

Within this small sample, the deadlift hold and dead hang protocols showed the largest average improvements. A likely reason is that these protocols combined maximal crush grip with additional loading: in the deadlift protocol, the hands supported a 135# barbell; in the dead hang protocol, they supported bodyweight. The combination of crush grip intent plus external load or bodyweight resistance may have increased the mechanical and neural demand on the grip compared to crush grip alone on the dynamometer.

Direct dynamometer practice still produced an 8 lb average improvement for that athlete, indicating that repeated maximal efforts against the testing device alone are sufficient to improve scores over a short cycle. Overall, both “specific practice” (dynamometer squeezes) and “loaded support holds” (deadlift holds and dead hangs) were effective, with the loaded options appearing to provide a larger training stimulus in this small, exploratory trial.

LIMITATIONS

• Small sample size (n = 4), with uneven numbers per protocol. Protocol-to-protocol comparisons should be considered tentative and exploratory.

NEXT STEPS

• Repeat this protocol comparison with a larger number of lab rats and more balanced group sizes in each method.
• Consider adding other grip-strength methods (for example, heavy farmer holds, thick-bar work, or dedicated grippers) as additional comparison protocols.

Questions, Comments, Feedback? Email emmett@mtntactical.com