Skip navigation
Life Fitness
Hammer Strength
Contact
Arabic - Arabic Dutch - Belgium Dutch - The Netherlands English - Belgium English - Europe English - Hong Kong SAR English - Netherlands English - United Kingdom English - United States French - Belgium French - France French - Switzerland German - Germany German - Switzerland Hungarian - Hungary Italian - Italy Italian - Switzerland Japanese - Japan Norwegian - Norway Portuguese - Brazil Portuguese - Portugal Simplified Chinese - China Spanish - Latin America Spanish - Spain Traditional Chinese - Hong Kong SAR Turkish - Turkey

Fitness Solutions for Your Market

Health Clubs

Hospitality

Multi-Unit Housing

Home Gyms

Sports & Athletics

Corporate & Medical Wellness

Equipment for All Training Types

Learn about our brands: Life Fitness Hammer Strength

Explore the full Equipment Catalog

Cardio

  • Treadmills
  • Ellipticals
  • Bikes & Indoor Cycles
  • Arc Trainers
  • Stair Climber & Stepper Machines
  • Rowers
  • Consoles

Strength Training

  • Selectorized
  • Plate Loaded
  • Racks, Rigs, & Platforms
  • Cable Machines & Functional Trainers
  • Benches
  • Storage Racks

Accessories

  • Dumbbells & Fixed Barbells
  • Barbells & Plates
  • Functional Training Accessories
  • Conditioning Accessories
  • Mobility Accessories

Digital Solutions

  • Life Fitness Connect
  • Facility Connect
  • Life Fitness™ On Demand+
  • Connect Kit

Integrity+ Cardio

Featured Lineups

Symbio Cardio Hammer Strength Performance Trainers LFX Empower potential

Support

Facility Layout

Service Hub

Education Hub

Plate Loaded Strength Training Equipment Catalog Home
hammer strength

Ground Base® Jammer

Built for raw power and explosive performance, the Hammer Strength Ground Base® Jammer is the real deal—no imitations, no compromises. While racks try (and fail) to mimic its movement, only the Jammer delivers the perfect blend of converging and diverging motion, unlocking true athletic drive. 

Designed in the ‘90s and still unmatched today, it’s the gold standard for developing force, power, and on-field dominance. When it comes to training like an athlete, there’s no substitute—there’s only the Jammer.

Dimensions (L x W x H): 79 in x 66 in x 83 in (202 cm x 167 cm x 212 cm)

Weight: 370 lb (168 kg)

View All Specs +

Life Fitness Brand Plate Loaded Ground Base® Jammer
Built for Explosive Power Unmatched Since the ‘90s Customize your own Jammer Product Specifications Product FAQs Additional Ground Base Products Accessories on this Product Riley Moss Contact Us
Contact


Built for Explosive Power

Athletes don’t just lift—they drive, push, and explode. The Ground Base® Jammer trains force production in the most athletic way possible, mimicking the powerful pressing movements seen in sport. Whether it's linemen battling in the trenches or sprinters driving out of the blocks, the Jammer builds the kind of strength that translates to real performance.

Unmatched Since the ‘90s

The Ground Base® Jammer isn’t new—it’s legendary. While other companies try to replicate its movement with half-measures, only Hammer Strength delivers the true Jammer experience. Designed in the mid-90s and still dominating weight rooms today, it remains the ultimate training tool for explosive strength.

Product Configurator

Customize your own Jammer

Customize your equipment like never before with our 3D configurator tool, featuring augmented reality to visualize and drop your design directly into your space.

Specs

Dimensions (L x W x H) 79 in x 66 in x 83 in (202 cm x 167 cm x 212 cm)
Weight 370 lb (168 kg)
Max Load Capacity (per arm) 4 x 45 lb plates (4 x 20 kg plates)
Starting Resistance 8 lbs (3.6 kg)
Product Code GB-J
Standard Weight Horns 6
Recommended Plate Mix 4 x 45 lb plates, 4 x 25 lb plates, 4 x 10 lb plates

FAQ

Rack-mounted press arms may look similar, but they don't move like a true Jammer. Without independent, converging, and diverging arms, they lack the natural pressing path that builds real-world power. The Jammer was engineered for explosive strength, allowing athletes to drive force through the ground while pressing in an athletic motion—something rack-mounted arms simply can't match.
Standing presses demand total-body activation. Instead of isolating the upper body, the Plate Loaded Jammer forces athletes to engage their core, legs, and hips to generate force—just like they would in competition. This builds functional power, improves coordination, and transfers directly to on-field performance.
Any athlete who needs explosive power, speed, and strength. Football players use it to build the drive and punch needed for the trenches. Combat athletes use it for powerful strikes. Sprinters and jumpers develop forceful hip extension. Whether it's contact sports, track and field, or any discipline requiring raw power, the Ground Base Jammer delivers.
Yes—but they're not the Jammer. Our Lightning Arms are lightweight yet durable pressing attachments designed for our HD Elite iD, HD Athletic NX, and HD Perimeter systems. They offer versatile pressing options, but for true explosive, ground-driven power, nothing replaces the original Hammer Strength Jammer.

Additional Ground Base Products

Ground Base Combo Twist
Ground Base® Squat / High Pull
Ground Base Multi-Squat

Accessories on this Product

Round Urethane Olympic Plates - 45 lbs
Round Urethane Olympic Plates - 25 lbs
Round Urethane Olympic Plates - 10 lbs

Riley Moss Our Athlete

  • NFL Cornerback
  • 2-Time All BIG10 Football Player
  • All-American
See other products Riley trains on

SCHEDULE A CONSULTATION WITH A LIFE FITNESS REPRESENTATIVE.

Step One

Specify and select your need below.

Customer Support

Step Two

Fill out the form with the required information.

EXPLORE OUR BRANDS
Life Fitness Hammer Strength
Arabic - Arabic Dutch - Belgium Dutch - The Netherlands English - Belgium English - Europe English - Hong Kong SAR English - Netherlands English - United Kingdom English - United States French - Belgium French - France French - Switzerland German - Germany German - Switzerland Hungarian - Hungary Italian - Italy Italian - Switzerland Japanese - Japan Norwegian - Norway Portuguese - Brazil Portuguese - Portugal Simplified Chinese - China Spanish - Latin America Spanish - Spain Traditional Chinese - Hong Kong SAR Turkish - Turkey

Markets

Health Clubs Hospitality Multi-Unit Housing Home Gyms Sports & Athletics Corporate & Medical Wellness

Equipment

Cardio Strength Training Accessories Digital Solutions

Customer Support

Facility Layout Service Hub Education Hub
About Find a Distributor Find a Store Legal Accessibility Careers Sign in to Facility Connect
Contact Us Privacy Settings Privacy Policy Terms and Conditions

Copyright © 2025 Life Fitness

Menu

  • Health Clubs
  • Hospitality
  • Multi-Unit Housing
  • Home Gyms
  • Sports & Athletics
  • Corporate & Medical Wellness
Learn about our brands:
Life Fitness Hammer Strength

Explore the full Equipment Catalog

  • Cardio
    • Treadmills
    • Ellipticals
    • Bikes & Indoor Cycles
    • Arc Trainers
    • Stair Climber & Stepper Machines
    • Rowers
    • Consoles
  • Strength Training
    • Selectorized
    • Plate Loaded
    • Racks, Rigs, & Platforms
    • Cable Machines & Functional Trainers
    • Benches
    • Storage Racks
  • Accessories
    • Dumbbells & Fixed Barbells
    • Barbells & Plates
    • Functional Training Accessories
    • Conditioning Accessories
    • Mobility Accessories
  • Digital Solutions
    • Life Fitness Connect
    • Facility Connect
    • Life Fitness™ On Demand+
    • Connect Kit
  • LFX
    • LFX - Virtual Tour
  • Hammer Strength Performance Trainers
  • Symbio Cardio
  • Integrity+ Cardio
  • Facility Layout
  • Service Hub
    • Service Solutions
    • Warranties
    • Battery Recycling
  • Education Hub
    • Life Fitness Academy
    • Blog
    • Ebooks
    • Whitepapers
    • Success Stories
    • Events
    • Press Releases
Contact
About Find a Distributor Find a Store Product Catalog Legal Careers Sign in to Facility Connect

My quote builder

For additional customizations, including color, material selections, weight options, etc., a sales representative will follow up with you.

Still Searching?

Looking for something specific?