{"product_id":"onyx-leg-extension","title":"ONYX Leg Extension","description":"\u003c!-- Product Description --\u003e\n\u003cp\u003eThe ONYX Leg Extension is a premium plate-loaded strength machine engineered specifically for quadriceps development with smooth, controlled knee extension performance. Built for commercial gyms and high-end personal training studios, its modern aesthetic and solid construction support reliable training in high-traffic environments.\u003c\/p\u003e\n\u003cp\u003eAn ergonomically contoured backrest is infinitely adjustable to accommodate users with different leg lengths, ensuring correct posture alignment and stable support throughout the full range of motion. A wide seat pad improves comfort for users with varying leg circumferences, while the ergonomically designed ankle roller follows the natural movement path of the lower leg for effective, joint-friendly quad activation. An isolated arm design supports unilateral training to reduce compensation and promote balanced strength development between both legs.\u003c\/p\u003e\n\n\u003cstyle\u003e\n.accordion-section {\n  margin-bottom: 10px;\n  border: 1px solid #ddd;\n  border-radius: 6px;\n  overflow: hidden;\n}\n.accordion-label {\n  display: block;\n  background-color: #f7f7f7;\n  padding: 12px;\n  font-weight: bold;\n  cursor: pointer;\n}\n.accordion-content {\n  max-height: 0;\n  overflow: hidden;\n  background: #fff;\n  padding: 0 12px;\n  transition: max-height 0.4s ease, padding 0.4s ease;\n}\ninput.accordion-toggle {\n  display: none;\n}\ninput.accordion-toggle:checked ~ .accordion-content {\n  max-height: 4000px;\n  padding: 12px;\n}\n.accordion-content ul {\n  margin: 0;\n  padding-left: 20px;\n  list-style-type: disc;\n}\n\u003c\/style\u003e\n\n\u003cdiv class=\"accordion-section\"\u003e\n  \u003cinput class=\"accordion-toggle\" id=\"accordion-onyx-leg-extension-features\" type=\"checkbox\"\u003e\n  \u003clabel for=\"accordion-onyx-leg-extension-features\" class=\"accordion-label\"\u003eKey Features\u003c\/label\u003e\n  \u003cdiv class=\"accordion-content\"\u003e\n    \u003cul\u003e\n      \u003cli\u003e\n\u003cstrong\u003ePlate-Loaded Leg Extension:\u003c\/strong\u003e Designed for isolated quadriceps training and controlled knee extension strength.\u003c\/li\u003e\n      \u003cli\u003e\n\u003cstrong\u003eInfinitely Adjustable Backrest:\u003c\/strong\u003e Easily adapts to different leg lengths for optimal posture alignment and training comfort.\u003c\/li\u003e\n      \u003cli\u003e\n\u003cstrong\u003eWide Seat Pad:\u003c\/strong\u003e Comfortable support for users with varying leg circumferences, improving stability during heavy sets.\u003c\/li\u003e\n      \u003cli\u003e\n\u003cstrong\u003eErgonomic Ankle Roller:\u003c\/strong\u003e Aligns with natural lower-leg movement path for smooth, effective quad activation.\u003c\/li\u003e\n      \u003cli\u003e\n\u003cstrong\u003eIsolated Arm Design:\u003c\/strong\u003e Supports unilateral training to reduce compensation and promote balanced left\/right strength development.\u003c\/li\u003e\n      \u003cli\u003e\n\u003cstrong\u003eStable Commercial Construction:\u003c\/strong\u003e Reinforced build designed for high-frequency use in commercial gym environments.\u003c\/li\u003e\n    \u003c\/ul\u003e\n  \u003c\/div\u003e\n\u003c\/div\u003e\n\n\u003cdiv class=\"accordion-section\"\u003e\n  \u003cinput class=\"accordion-toggle\" id=\"accordion-onyx-leg-extension-training\" type=\"checkbox\"\u003e\n  \u003clabel for=\"accordion-onyx-leg-extension-training\" class=\"accordion-label\"\u003eTraining Options\u003c\/label\u003e\n  \u003cdiv class=\"accordion-content\"\u003e\n    \u003cul\u003e\n      \u003cli\u003e\n\u003cstrong\u003eLeg Extension:\u003c\/strong\u003e Primary quad isolation movement to build knee extension strength and muscle definition.\u003c\/li\u003e\n      \u003cli\u003e\n\u003cstrong\u003eQuadriceps Hypertrophy:\u003c\/strong\u003e Ideal for controlled volume training to build quad size, shape, and endurance.\u003c\/li\u003e\n      \u003cli\u003e\n\u003cstrong\u003eStrength Development:\u003c\/strong\u003e Plate-loaded progression supports heavier training and progressive overload programming.\u003c\/li\u003e\n      \u003cli\u003e\n\u003cstrong\u003eUnilateral Quad Training:\u003c\/strong\u003e Train one leg at a time to improve symmetry and correct muscular imbalances.\u003c\/li\u003e\n      \u003cli\u003e\n\u003cstrong\u003eLower-Body Accessory Work:\u003c\/strong\u003e Complements squats, leg press, hack squat, and athletic performance routines.\u003c\/li\u003e\n    \u003c\/ul\u003e\n  \u003c\/div\u003e\n\u003c\/div\u003e\n\n\u003cdiv class=\"accordion-section\"\u003e\n  \u003cinput class=\"accordion-toggle\" id=\"accordion-onyx-leg-extension-specs\" type=\"checkbox\"\u003e\n  \u003clabel for=\"accordion-onyx-leg-extension-specs\" class=\"accordion-label\"\u003eProduct Specifications\u003c\/label\u003e\n  \u003cdiv class=\"accordion-content\"\u003e\n    \u003cul\u003e\n      \u003cli\u003e\n\u003cstrong\u003eDimensions (L × W × H):\u003c\/strong\u003e 63.0 × 63.0 × 49.6 in\u003c\/li\u003e\n      \u003cli\u003e\n\u003cstrong\u003eTotal Weight:\u003c\/strong\u003e 243 lb\u003c\/li\u003e\n      \u003cli\u003e\n\u003cstrong\u003eResistance Type:\u003c\/strong\u003e Plate-loaded\u003c\/li\u003e\n      \u003cli\u003e\n\u003cstrong\u003eTarget Muscle Groups:\u003c\/strong\u003e Quadriceps (primary)\u003c\/li\u003e\n      \u003cli\u003e\n\u003cstrong\u003eIntended Use:\u003c\/strong\u003e Commercial gyms and high-traffic training facilities\u003c\/li\u003e\n    \u003c\/ul\u003e\n  \u003c\/div\u003e\n\u003c\/div\u003e\n\n\u003cdiv class=\"accordion-section\"\u003e\n  \u003cinput class=\"accordion-toggle\" id=\"accordion-onyx-leg-extension-why\" type=\"checkbox\"\u003e\n  \u003clabel for=\"accordion-onyx-leg-extension-why\" class=\"accordion-label\"\u003eWhy Choose ONYX\u003c\/label\u003e\n  \u003cdiv class=\"accordion-content\"\u003e\n    \u003cul\u003e\n      \u003cli\u003eInfinitely adjustable backrest supports proper alignment for more effective quad training\u003c\/li\u003e\n      \u003cli\u003eErgonomic ankle roller improves comfort and ensures smoother reps\u003c\/li\u003e\n      \u003cli\u003eIsolated arms enable unilateral training to build balanced lower-body strength\u003c\/li\u003e\n      \u003cli\u003eCommercial-grade construction designed for daily high-traffic use\u003c\/li\u003e\n    \u003c\/ul\u003e\n  \u003c\/div\u003e\n\u003c\/div\u003e\n","brand":"VO3 Fitness","offers":[{"title":"Default Title","offer_id":59780449501265,"sku":null,"price":2499.0,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/1050\/9418\/files\/ONYXLegExtension_1.png?v=1783632222","url":"https:\/\/spartanfitness.ca\/products\/onyx-leg-extension","provider":"Spartan Fitness Equipment","version":"1.0","type":"link"}