MTI Mini-Study: 10-Minute Sandbag Get-Up Progression Increases Get-Up Performance but Fails to Sustain Broader Chassis Integrity Gains

By Jackson Mann

BLUF (Bottom Line Up Front)

MTI tested three sandbag get-up progression models over four weeks to determine which most effectively improved 10-minute max-rep performance. All four athletes significantly improved their get-up totals—ranging from +24% to +123%. However, when comparing July’s chassis integrity reassessment with June’s end-of-cycle results, athletes showed declines across all four core integrity metrics. These findings suggest that while the sandbag get-up trains the chassis in total it fails to develop isolated movements when used alone.

Key Outcomes

● Seung (Daily Fire progression) recorded the largest percentage improvement: +123%
● All athletes improved their 10-minute get-up scores regardless of progression used
● Chassis integrity performance declined across all four domains (flexion, extension, isometric, and rotation) when compared to June’s final assessments

Athlete Results

Background

Chassis integrity—the strength, endurance, and control of the midsection under load—is a focus of MTI’s strength and conditioning programming. Rather than training the “core” in isolation through abdominal-focused movements, MTI defines chassis integrity as the functional bridge between the upper and lower body. This includes the ability to transmit force, resist collapse, and sustain posture under fatigue, awkward loads, and unpredictable movement patterns.

To quantify this concept, we developed a four-part chassis integrity assessment that isolates the chassis across key movement planes:
● Flexion: Sandbag Sit-Ups
● Extension: Barbell Good Mornings
● Rotation: Sandbag Keg Lifts
● Isometric Control: Weighted Elevated Bridge Hold

This model was used in MTI’s June Geek Cycle and successfully produced improvements across all metrics. However, the format revealed significant challenges in execution: the full assessment took over an hour to complete and loads required adjustments for athletes with stronger chassis.

As a result, we launched this mini-study to test a more practical alternative: the sandbag get-up. This compound movement inherently incorporates all four movement demands—flexion, extension, rotation, and isometric stability.

The goal of this study was twofold:

1. To compare the effectiveness of three sandbag get-up training progressions in improving 10-minute max-rep performance with an 80-lb sandbag.

2. To evaluate whether improvements in the sandbag get-up would carry over to June’s Geek Cycle four-part chassis integrity assessment.

Study Design

Training Period (July 7–30)
Athletes trained 2–3x/week using one of three assigned progression models:

● Approach A: Operator Ugly Progression (Sam)
10-round EMOM based on 10% of max reps from the baseline test, adding +1 rep per round each session.

● Approach B: Daily Fire Progression (Seung)
Three 5-minute rounds of submaximal effort. Athletes began at 40% of their baseline get-up total and progressed to 50% by the final week.

● Approach C: Straight 10-Minute Volume (Jackson, Emmett)
Continuous, unbroken 10-minute efforts focused on pacing and total work output.

No other chassis-specific training (e.g., sit-ups, good mornings, keg lifts, bridges) was performed during this period to isolate the impact of the get-up progressions.

Final Get-Up Reassessment (July 28)

Athletes repeated the 10-minute max-effort sandbag get-up test using the same environment, equipment, and rep-counting protocols as the initial assessment. This allowed for direct pre/post comparisons of each progression’s effectiveness.

Chassis Integrity Reassessment (July 30)

Two days later, athletes completed MTI’s four-part chassis integrity test:
● Sandbag Sit-Ups (90 seconds, 60–80 lbs based on prior loading)
● Barbell Good Mornings (90 seconds at 95 lbs)
● Weighted Bridge Hold (timed hold with 25 or 45 lbs)
● Sandbag Keg Lifts (90 seconds, 60–80 lbs)

Chassis Integrity Comparison: June vs. July

Discussion

All three progression models effectively improved 10-minute sandbag get-up scores. Seung, using the Daily Fire progression, saw the largest percentage gain. The Straight 10-Minute model and Operator Ugly progression delivered steady results for Jackson, Emmett, and Sam.

However, improvements in the get-up did not translate to sustained or improved scores in the broader four-part chassis integrity assessment. Every athlete who completed the reassessment saw substantial decline in all four domains (sit-ups, good mornings, keg lifts, bridge) with the exception of Sam who increased his weighted bridge by a few seconds. This suggests that while the get-up does engage flexion, extension, rotation, and isometric tension, it does not provide enough volume or specificity to maintain those qualities in isolation.

It’s important to note that Sam, Jackson, and Seung had no prior experience with the sandbag get-up before the June assessment. By the July reassessment, their improved familiarity and efficiency likely contributed to higher increases in that specific movement despite no direct training. Emmett, on the other hand, had previously trained sandbag get-ups in previous training and began the cycle with a more refined technique—so his results were likely a more accurate reflection of expected gains in get ups for athletes familiar with the movement.

In sum, the 10-minute sandbag get-up is a valuable and efficient training tool, but it does not fully replace isolated chassis training when the goal is to develop or maintain strength endurance across all chassis integrity movement patterns.

Limitations

This study was limited by a small sample size (n=4), which restricts the generalizability of the findings. Each athlete followed only one progression model, so individual differences in adaptation or background could have influenced results more than the progression itself.

Jackson did not complete the sit-up reassessment due to back abrasions, resulting in incomplete data for one of the four chassis domains.

Next Steps

Based on the outcomes of this study, we will begin restructuring the chassis integrity assessment to balance logistical simplicity with performance relevance. We may also take the chassis integrity assessment and redo it entirely.

While the 10-minute sandbag get-up proved to be an effective integrated training movement and assessment tool, it did not adequately preserve chassis integrity markers when used in isolation.