Flex Fitness Hamtractor

Name: Flex Fitness Hamtractor
Brand: Flex Fitness
Rating: 5.0 (3 reviews)

The Hamtractor is a seated leg curl machine from Flex Fitness that’s become a cult favorite among commercial gym owners, but it hasn’t been manufactured in years — the only way to get one today is a used listing from a vintage-equipment dealer. Its draw is a roller pad whose pivot lines up precisely with the knee, so reviewers can confirm correct alignment by watching whether the roller stays still (aligned) or rolls during the movement (not aligned). A fully adjustable seat and back pad, plus lift-assist handles that raise the stack into position before you swing your legs onto the pad, make it possible to lock in a snug, cheat-resistant setup. Pointing the toes up versus down shifts the emphasis higher or lower on the hamstring, letting lifters vary the exercise within a single set.

Buying guide

Best GHD for a Home Gym — July 2026

Adjustments	Adjustable seat and back pad (fore/aft and height); lift-assist handles to pre-load the stack; toe-up/toe-down foot position to shift hamstring emphasis
Availability	Discontinued — resale/used market only, no current manufacturer listing
Weight stack	285 lbs.
Movement type	Seated hamstring curl, plate/stack-loaded
Machine weight	400 lbs.
Footprint width	40"
Footprint height	51"
Footprint length	70"

What is a Machine?

What a strength machine is

A strength machine guides the resistance along a fixed path so you can train a movement safely, often without a spotter. The main types: selectorized (pick weight with a pin), plate-loaded (add your own plates for a heavier ceiling and better feel), and functional trainers / cable machines (adjustable pulleys for dozens of exercises).

Machines vs. free weights

Machines shine for isolation, safety, and high-rep hypertrophy, and for training hard alone. Free weights build more stabilizer strength and carry over better to sport. Most well-rounded home gyms use a rack and barbell as the core and add one machine — often a cable/functional trainer or a lat-pulldown/row — to fill the gaps.

The sub-types worth knowing

“Machines” covers several categories that barely compete with each other: GHDs for hamstring and posterior-chain work, belt squats for loading the legs without the bar on your back, leg press / hack squat combos for heavy quad volume, reverse hypers for posterior-chain work and lower-back decompression, cable towers and functional trainers for pulling movements, and row machines. Pick the one that fills a gap in what your rack and barbell already do. Almost nobody needs two.

Space and standalone vs. rack-mounted

Most of these come in a standalone version and a cheaper rack-attachment version. The attachment saves floor space and money, but often gives up stability or range of motion — a tradeoff worth checking on the specific product rather than assuming, since it varies a lot between designs.

A note on ratings

Machine listings frequently show a manufacturer’s own on-site rating, which runs high (4.7–5.0 is typical) and sometimes pools reviews across a whole product family rather than the exact configuration you’re buying. Where we have independent hands-on coverage, our summaries anchor to that instead, and say so on the product page.

How it compares

	Flex Fitness Hamtractor	Athena® Selectorized Side-Mount Functional Trainer	Hack squat pro	Arcadia™ Functional Trainer
GymRadar rating	5.0/5	5.0/5	5.0/5	5.0/5
Price		$949.99	$10,850.00	$2,199.99
Adjustments	Adjustable seat and back pad (fore/aft and height); lift-assist handles to pre-load the stack; toe-up/toe-down foot position to shift hamstring emphasis
Availability	Discontinued — resale/used market only, no current manufacturer listing
Weight stack	285 lbs.	170 lbs per side stock (feels like 85 lbs at 2:1 ratio); upgradeable to 220 lbs per side (feels like 110 lbs)
Movement type	Seated hamstring curl, plate/stack-loaded
Machine weight	400 lbs.
Footprint width	40"
Footprint height	51"
Footprint length	70"

5.0/5 · 3 GymRadar reviews

Reviews by source

Expert	5.0/5	3 reviews
Youtube	4.7/5	2 reviews	Two independent gym-floor demo videos both call it arguably the best seated leg curl ever made — precise pivot alignment and adjustable seat/back pad make for a cheat-resistant curl; only knock is a short trial-and-error period to dial in alignment on first use.

The Hamtractor is a discontinued Flex Fitness seated leg curl that’s become a cult favorite among commercial gym owners for its precise pivot alignment and a toe-angle trick for shifting hamstring emphasis mid-set — both GymRadar’s small sample and independent demo videos describe it as one of the best seated leg curls ever made. Functionality is the standout: an adjustable seat and back pad, lift-assist handles, and a roller pad that tracks the knee pivot combine for a genuinely cheat-resistant curl. Value is the weakest dimension by far — it hasn’t been manufactured in years, so the only way to get one is a resale listing with no fixed price, which makes it a poor buy for anyone not already committed to hunting one down.

+Functionality: The roller pad's pivot lines up precisely with the knee, and pointing the toes up vs. down shifts emphasis higher or lower on the hamstring mid-set (YouTube: Prodigy Gym and Fitness)
+Functionality: Lift-assist handles pull the stack into loaded position before you swing your legs onto the pad, and full seat/back-pad adjustability locks in a snug, cheat-resistant fit (YouTube: mr. Fit world)
+Build quality: 285 lb. weight stack in a heavy iso-lateral-style frame; three separate resale listings each describe their unit as being in excellent condition and working order (Fitness Equipment Empire)
+Durability: Units changing hands are typically decades old and still fully functional, which is the strongest durability signal available for a discontinued machine (Fitness Equipment Empire, Exercise Unlimited)

−Value: No manufacturer or retailer sells it new — every listing found is resale-only and unpriced ('contact for pricing'), and rarity pushes asking prices up unpredictably (Fitness Equipment Empire, Exercise Unlimited)
−Versatility: Single-purpose seated hamstring curl with no complementary stations — every source describes only the one movement
−Functionality: Alignment takes real trial and error the first time; reviewers note you need a few practice reps to find the correct pivot point before it feels right (YouTube: mr. Fit world)
−Durability: Independent coverage is thin (a 3-review GymRadar aggregate plus two demo videos), so long-term reliability data beyond 'still works on old units' is limited