What is a tendon, and what is its composition?
A tendon is a structure made of dense connective tissue that connects muscles to bones—transmitting the force of muscle contraction to produce movement. It is characterized by its poor blood supply, which explains why it heals slowly and why targeted nutrition is so important. Our joint collagen line offers active ingredients that support tendon synthesis.
- Composition: 65–80% type I collagen (parallel fibers that are extremely resistant to tension) — extracellular matrix — tenocytes (cells that synthesize collagen) — water (55–70%)
- Mechanical strength: The Achilles tendon can withstand up to 12 times the body’s weight while running—the rotator cuff tendons withstand the repeated stresses of arm movements
- Poor vascularization: limited blood supply → slow healing (4–12 weeks for a partial tear) → dependence on nutrients supplied by synovial fluid and the peripheral circulation
- Main tendons at risk: Achilles tendon (running and jumping), rotator cuff (shoulder, overhead arm movements), patellar tendon (jumper’s knee), finger flexor tendons (manual labor)
How can nutrition help maintain tendon health?
Tendon nutrition is specific—the active ingredients that support type I collagen synthesis are the most well-documented for tendon health and recovery. Find these formulas in our joint collagen and sports wellness lines.
- Hydrolyzed marine collagen: directly provides glycine, proline, and hydroxyproline—structural amino acids of tendon collagen—take 15 g/day 30–60 minutes before strength training to maximize synthesis
- Vitamin C: an essential cofactor for prolyl hydroxylase—the enzyme that stabilizes collagen’s triple helix—500 mg per day—collagen’s effectiveness is significantly reduced in the event of a vitamin C deficiency
- Total protein: 1.5–2 g/kg/day — tenocytes require an adequate protein intake to synthesize new collagen during tendon repair
- Zinc: a cofactor for metalloproteinases involved in tendon remodeling — 10–15 mg/day
- Omega-3 (EPA/DHA): Modulate the tendon inflammatory response — promote flexible healing without excessive fibrosis
Tendon Injuries: Tendinitis, Tendinosis, and Rupture
Tendon disorders form a spectrum—ranging from acute inflammation to complete rupture—each requiring specific treatment. For details by location, see our tendinitis page.
- Acute tendinitis: true inflammation—heat, swelling, sharp pain—treatment: cold + rest + topical NSAIDs—short-term phase (a few days)
- Chronic tendinosis: collagen degeneration without inflammation—a “cotton-like” appearance on MRI—treatment: eccentric strengthening for 12 weeks + collagen + vitamin C
- Partial tear: tear of a portion of the fibers—acute pain + functional weakness—MRI essential for assessment—conservative or surgical treatment depending on the extent
- Complete rupture: total loss of continuity—cracking sound + inability to contract—surgical emergency (Achilles tendon, rotator cuff)—immobilization + suturing + long-term rehabilitation (6–12 months)
- Fluoroquinolones: 4-fold increased risk of tendinitis and rupture — immediate discontinuation if tendon pain occurs while taking antibiotics in this class
Eccentric strengthening and advanced treatments for tendinopathies
- Eccentric strengthening: muscle contraction during lengthening (slow lowering) — stimulates tendinous collagen synthesis — Alfredson protocol (Achilles) and similar programs — 12 weeks of rigorous training required for a lasting effect
- Extracorporeal shock waves: stimulate blood flow and collagen synthesis — recommended by physical therapists for chronic, treatment-resistant tendinosis
- PRP (platelet-rich plasma): injection of autologous growth factors — accelerates tendon collagen regeneration — an option prior to surgery or for refractory cases
- Surgery: resection of degenerated tissue (tenotomy), suturing of tears—a last resort after conservative treatments have failed for > 6 months
- Return to sports: after treated tendinosis — strength ≥ 90% of the healthy side + no pain during exertion + specific movement tested — never based on a fixed timeframe alone
