After the successful development of GORUCK’s very first footwear item, The MACV-1, the jungle boot team was back together for a new challenge: a training shoe. Spearheaded by Paul Litchfield, shoe dog and inventor of the Reebok Pump, they were ready to break the rules.
Our goal was to create the best functional fitness shoe on the market. From the get go, we knew we wanted to create a flexible forefoot with breathability along with a structured midfoot and heel to create stability and abrasion resistance. We used biomechanical research, material science and the best shoe construction techniques to create the Ballistic Trainer.
REFINING THE MATERIALS
Initially, we chose SuperFabric for the midfoot and heel, however, the material did not provide the durability and support we needed and it did not look cool. We experimented with 1680D Ballistic Nylon (one of the toughest fabric materials available) and determined the 1680D was the best material for midfoot/heel support and resistance to abrasion encountered in rope climbing.
We wanted the front knit area to be flexible, but the first versions were TOO flexible. Your toes shouldn’t be able to poke out the top.
We went back to the engineered knitting factory and worked with them on dozens of different knit patterns to determine the best possibilities for the combination we needed in the forefoot of the shoe; flexibility when pushing off your toes, reinforcement around the front to eliminate toes pushing through the fabric and breathability on the top of the forefoot
TOE CAP OPTIONS
We investigated different toe cap overlays for reinforcing the toe area. By modifying the engineered knit pattern, we were able to create the reinforcement necessary without a reinforcing overlay. The one piece specifically designed engineered knit pattern was the best performing and lightest weight option.
THE LACE DESIGN
We also went through a number of lace system options. We wanted to have the lacing system compliment the 1680D Ballistic Nylon midfoot cage by allowing the athlete to really tighten this cage around the foot while also making the lace system not interfere when using the J-Hook technique in rope climbing.
A shoe last, pictured above, is critical in developing a shoe because the shape of the last determines the fit, performance, ergonomics, and style of a shoe. The last must match the shoe’s function. Ours was built to have generous forefoot volume with a medium width forefoot base and most importantly an 8mm drop.
We tested zero heel drop, 4mm heel lift and 8mm in blind weartests (the testers did not know which shoe was which). Despite a popular opinion in the functional fitness space that zero drop is the way to go, the 8mm heel lift midsole option was overwhelmingly preferred for lifting performance and under foot stability. The 8mm heel lift provides better mechanical advantage which allowed our testers to maximize their power output.
The outsole is made up of 3 different compounds that you can see in the colors green, yellow, and blue above. The green forefoot compound is high traction for excellent grip during fast movements. The blue heel compound is high abrasion with good traction for heel strike and underfoot stability The yellow is an extremely highly abrasion resistant material that is used in mountain climbing shoes to provide the ultimate performance in rope climbing. After a number of weartests, we positioned these materials in the three zones (pictured on left) to give the maximum performance for each.
THE FINAL PRODUCT
Here are the final drawings for what we were calling the X-Fit trainer, but is much better known (for good reason) the Ballistic Trainer.
– Paul Litchfield
30 Year Shoe Dog, Inventor of the Reebok Pump (and 160+ other patents)
Senior Director, GORUCK Footwear