Above: The author lab rats the prone to sprint portion of the Urban Fire work capacity event.
By Emmett Shaul
December 30, 2025
Before MTI publishes a training plan, it is tested. Programming is built in-house, then trained ahead of release by MTI coaches and lab rats. If the first iteration does not hold when trained as written, it is refined and tested again. This process continues until the programming holds under real work.
Recently, we applied this process to two separate but related efforts:
- a 10-minute work capacity progression for Urban Fire Rescue Sessions, and
- a new working strength methodology for the bench press.
Both efforts began with specific performance requirements. Testing exposed where the initial designs broke down. From there, we adjusted the programming and re-tested until each effort met its intent.
Urban Fire Work Capacity Event
The task for the Urban Fire Rescue work capacity effort was to build a 10-minute event that could progress across four weeks. In a well-designed work capacity event, the athlete reaches both cardiovascular and muscular failure near the end of the prescribed duration—not early, and not due to a single limiting factor.
Good work capacity design is as much art as science. Beyond duration, there are several common mistakes that undermine the intent of “work capacity.” One of the most frequent errors is loading too heavy. If an exercise requires rest within a round in order to complete the prescribed reps, the load is too heavy. Rest allows heart rate to drop, and maintaining an elevated heart rate is a primary objective of work capacity training.
In this case, exercise selection was not the issue. The challenge was designing the rep and interval structure—specifically, how to create a multi-modal event that landed at the correct duration and could be progressed over four weeks without degrading into poor design.
The event was built around a loaded movement and a sprint: sandbag clean and press paired with 40-foot prone-to-sprints. Four prone-to-sprints work well for 10-minute efforts because the work interval stays short and, after the fourth sprint, the athlete returns to the starting point. Choreography matters in work capacity design.
The first iteration was intentionally simple:
10 Rounds, Every 1:00
4x Sandbag Clean and Press @ 60 lb
4x 40-foot Prone-to-Sprint
— The faster the athlete finishes, the more rest they earn before the next round
The clean and press was set at four reps because it is easy to remember under fatigue—“4 and 4.” Simplicity matters during high-intensity efforts, but simplicity alone does not guarantee good design.
From the outset, the progression plan was to keep the work constant and reduce rest across the four-week progression. Shortening the interval increases density without increasing volume. Adding reps, particularly to the clean and press, would have pushed shoulder volume too high—a common failure point in work capacity design. When every exercise stresses the same limitation—shoulders, low back, or grip—the athlete stops because that area fails, not because the event is properly balanced.
Tightening the interval allowed us to increase difficulty without overworking the shoulders.
Where the First Iteration Failed
After testing the first iteration, the event did not hold across all ten rounds. Rest became insufficient in the later rounds, output dropped, and the work/rest balance degraded.
We adjusted the design. The interval was extended to 1:05, and sandbag clean and press reps were reduced from four to three. The prone-to-sprints remained unchanged. From there, the event progressed by tightening the interval in five-second increments:
- Progression 1: 10 Rounds, Every 1:05
- Progression 2: 10 Rounds, Every 1:00
- Progression 3: 10 Rounds, Every :55
At the top of the progression, the event became:
10 Rounds, Every :50
3x Sandbag Clean and Press
4x 40-foot Prone-to-Sprint
We tested the event at the top of the progression to confirm two things: that shoulder volume remained appropriate, and that the event was sustainable at the tightest interval. Testing occurred the week after an intense 20-minute Touch/Jump/Touch to Box progression—one of MTI’s most demanding work capacity efforts—so fitness levels were sufficient to evaluate the top end.
The event held. Output remained sustainable, rest was appropriate, and shoulders were not overworked.
Bench Press Working Strength
At the same time, we were testing a 10-minute working strength interval for the bench press. Working strength sits between max-effort strength and strength endurance. It is the ability to lift a high percentage of 1RM for repeated reps—too heavy, and generally too few reps, to be classified as strength endurance.
Unlike progressions that increase load weekly while keeping reps constant, working strength can also be developed by accumulating more reps at a fixed load.
We had already run a similar progression successfully for the hinge (deadlift). In that progression, athletes tested a 1RM, then used 75% of 1RM for the initial progression:
50 Rounds, Every 12 Seconds
1x Hinge Lift @ 75% 1RM
The hinge lift recruits significantly more and larger muscle groups—glutes, hamstrings, quads, and spinal erectors—than the bench press. Bench pressing relies primarily on the pecs, triceps, and shoulders. While we wanted to maintain the same overall structure—10 minutes, 50 total reps—we were uncertain about the appropriate starting percentage for the bench press.
We first tested 75% 1RM. I completed just 15 of 50 rounds before failing. Another lab rat, Michael, completed just 16. That result ruled out 75% as a viable starting point.
After a rest day, we re-tested. Michael tested 60% and completed all 50 rounds, reporting it was manageable. I tested 65%. It was difficult but sustainable. 65% 1RM became the starting point for the bench press working strength progression:
50 Rounds, Every 12 Seconds
1x Bench Press @ 65% 1RM
Progression Model
Working strength can be progressed by either adding reps or increasing load. In this case, due to the narrow 12-second interval, we chose to increase load while maintaining the same structure.
The second progression moved to:
- 80% 1RM for hinge lift
- 70% 1RM for bench press
Subsequent progressions continued to increase load (85/75, etc.). Each progression is trained for two sessions. After the third progression, athletes re-assess 1RM before restarting the cycle.
This is the general programming method for all MTI programming.
First comes the idea.
Next comes testing and measurement.
Iteration then re-testing, etc. … until we get it right.
Only then do we publish.
Questions?
Email: Emmett@mtntactical.com