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Hack Squat vs Pendulum Squat — Full Comparison, Muscle Activation & Best Home Gym Options

December 01, 2025

When it comes to building strong, powerful legs at home, two machines stand above the rest: the Hack Squat and the Pendulum Squat. Both are designed to target your quads, glutes, and hamstrings—but they deliver a very different training experience. If you're designing or upgrading your home gym, understanding these differences will help you make the right investment.

In this comparison, we break down biomechanics, muscle activation, benefits, and which machine suits different training styles. We’ll also show you specific options available at GearForFit.

What Is a Hack Squat?

A Hack Squat is a machine where you stand at an angle with your back fixed against a pad while your feet are placed on an elevated platform. As you lower into a squat, the machine guides your movement along a set track. This creates an extremely stable environment, making it ideal for lifting heavy and isolating the legs.

Key Characteristics of a Hack Squat

  • Angled track that guides the motion
  • Fixed back support for extra stability
  • High quad activation with less balance demand
  • Very stable and predictable movement pattern
  • Beginner-friendly and easy to learn

Hack Squat Options at GearForFit

If you’re looking for a hack squat for your home or semi-commercial gym, consider:

What Is a Pendulum Squat?

The Pendulum Squat uses a swinging arm that moves in a natural arc. This creates a variable strength curve throughout the movement—heavier at the top, lighter at the bottom—which mimics how your legs naturally produce force. As a result, the exercise feels smooth, powerful and joint-friendly, even at higher loads.

Key Characteristics of a Pendulum Squat

  • Arc-shaped pendulum motion instead of a fixed straight track
  • Smooth, natural biomechanics that match your strength curve
  • Deep, controlled range of motion
  • Extremely joint-friendly on knees and lower back
  • Ideal for athletic performance, muscle growth and advanced leg training

Pendulum Squat Options at GearForFit

For pendulum squat machines, you can choose from:

  • GF PHOENIX PENDULUM SQUAT — a premium pendulum squat machine with consistent resistance from start to finish, an adjustable rubber stop and a forward-rotating spotter arm for safety and control.
  • GF Pendulum Squat Max Leg Press — a pendulum-style leg press and squat combo that offers full range-of-motion leg training with heavy load capacity, perfect for serious lifters who want maximum versatility.

Hack Squat vs Pendulum Squat: Muscle Activation

How the Hack Squat Loads Your Legs

The hack squat places a heavy emphasis on your quadriceps, especially the lower portion of the thigh (vastus medialis). Because the movement is guided and stable, you can safely overload the quads with substantial weight. This makes the hack squat a favorite for building overall quad thickness and lockout strength.

How the Pendulum Squat Loads Your Legs

The pendulum squat keeps tension on the legs through a long range of motion and shifts the focus through different parts of the quads and glutes:

  • Upper quads
  • Glutes, especially at the bottom of the movement
  • Hamstrings during the eccentric (lowering) phase
  • Outer quad sweep (vastus lateralis)

Because of the arc motion and resistance curve, the quads stay engaged longer, creating a deep burn and strong hypertrophy stimulus.

Biomechanics: Which Is Better for Knees & Lower Back?

Hack Squat: Stable but Demanding

The fixed track of a hack squat provides excellent stability but can, depending on foot placement and individual mechanics, place more pressure on the knees. For most lifters, this is manageable and even beneficial, but those with a history of knee pain should be mindful of stance and depth.

The hack squat is:

  • Great for beginners who need stability
  • Ideal for heavy quad work
  • Potentially stressful for the lower back if you round at the bottom or go too deep

Pendulum Squat: Extremely Joint-Friendly

The pendulum squat is widely considered one of the most knee-friendly squat variations. Its arcing motion reduces pressure at the bottom of the squat while still maintaining strong muscular tension. This makes it a fantastic option if you:

  • Have a history of knee discomfort
  • Struggle with lower back issues
  • Have limited ankle mobility but still want deep squats

Which Machine Builds More Muscle?

Both machines can build impressive strength and muscle, but they shine in slightly different ways:

For Pure Hypertrophy (Muscle Growth): Pendulum Squat

The pendulum squat’s resistance curve keeps the muscles working hard throughout the entire movement and significantly increases time under tension. This is ideal for lifters who want maximum hypertrophy with a smooth, controlled feel.

For Progressive Overload and Heavy Strength Work: Hack Squat

The hack squat’s stability makes it easier to load heavy and push near your limits safely. If your primary goal is to progressively add plates and drive up leg strength, the hack squat offers a very straightforward path.

Which Is Better for a Home Gym?

Choose a Hack Squat If You Want:

  • The ability to lift heavy with confidence
  • A machine that’s easy and intuitive for beginners
  • Maximum quad isolation and stability
  • A slightly smaller and more compact footprint

Choose a Pendulum Squat If You Want:

  • The smoothest, most natural squat biomechanics
  • A very knee- and back-friendly leg day
  • Deep range of motion with constant muscle tension
  • A modern, premium leg-training experience

If you have limited space, a compact hack squat or a combined leg press + hack squat unit (such as the GF Leg Force Fusion or GF TN Leg Press / Hack Squat Machine ) can be the most practical solution.

If you’re building an elite or semi-commercial home gym and want the most comfortable, joint-friendly squat possible, a pendulum unit like the GF PHOENIX PENDULUM SQUAT or GF Pendulum Squat Max Leg Press is absolutely worth the space.

Final Verdict: Which One Should You Buy?

You really can’t go wrong with either machine—both deliver massive leg development. The right choice depends on your training style, your joints, and your available space:

  • Choose the Hack Squat if you love stable, heavy quad work and want a straightforward way to overload your legs.
  • Choose the Pendulum Squat if you want premium biomechanics, a very joint-friendly experience, and deep hypertrophy with a smooth feel.

In high-end home gyms, both machines complement each other perfectly. But if you must choose just one, most lifters today lean toward the pendulum squat for its superior comfort and muscle engagement.

Upgrade Your Leg Day with GearForFit

Ready to upgrade your home gym? Explore these featured lower-body machines:

Build the lower body you’ve always wanted—right at home.

Click here to find your gear