Recovery

After a season of swim-bike-run training, racing, and the accumulated micro-damage of thousands of repetitive loading cycles, the triathlon off-season is not a break from training — it is a strategic recovery and rebuilding period. Tendons, which adapt 3–10 times more slowly than muscle tissue, bear the brunt of multi-sport training: the Achilles tendon absorbs 6–8 times body weight with each running stride, the patellar tendon withstands 3,000–5,000 loading cycles per hour of cycling, and the rotator cuff tendons experience fatigue from 1,500+ swim strokes per hour. By season's end, these structures carry accumulated micro-damage that — if not addressed — becomes the tendinopathy that sidelines athletes in the first 6–8 weeks of the next season.

A 2022 prospective study of 420 age-group triathletes found that those who followed a structured off-season tendon rehabilitation and aerobic maintenance programme had a 62% lower injury rate in the first 12 weeks of the following season compared to those who either stopped training entirely or jumped straight into structured work without a rebuild phase. The off-season sweet spot is 6–8 weeks of targeted tendon loading, controlled aerobic maintenance, and nutritional support for collagen synthesis.

Tendon Collagen Turnover: The 48–72 Hour Rule

Tendon adaptation follows a fundamentally different timeline than muscle adaptation. When a tendon is loaded (through running, jumping, or heavy resistance exercise), collagen synthesis peaks at 24 hours post-loading and remains elevated for 48–72 hours. However, collagen degradation also peaks — at 24–36 hours — creating a net-positive synthesis window only between 36–72 hours post-loading. This means loading tendons every day actually accelerates breakdown faster than synthesis, while loading every 48–72 hours optimises net collagen production.

During the off-season, structure tendon-loading sessions (heavy slow resistance, isometrics, or plyometrics) every 2–3 days, with lighter aerobic work on the intervening days. This contrasts sharply with in-season training, where daily loading is often unavoidable. The off-season is the only period where you can respect this biological timeline.

The Gelatin + Vitamin C Protocol

A protocol developed at the Australian Institute of Sport and validated in multiple studies has shown that consuming 15 g of gelatin (or hydrolysed collagen) with 200 mg of vitamin C 30–60 minutes before tendon-loading exercise increases collagen synthesis rate by 50–100% compared to loading alone. Vitamin C is a required cofactor for prolyl hydroxylase, the enzyme that stabilises collagen triple-helix structure. Without adequate vitamin C, newly synthesised collagen is structurally weak.

• Dose: 15 g gelatin or hydrolysed collagen peptides + 200 mg vitamin C
• Timing: 30–60 minutes before each tendon-loading session
• Form: Dissolve gelatin in warm water or juice. Collagen peptides can be mixed in cold liquid. Add a vitamin C tablet or 200 ml of orange juice (provides ~100 mg vitamin C — supplement the remaining 100 mg).
• Duration: Throughout the entire 6–8 week off-season rebuild. Benefits are cumulative — studies show measurable tendon cross-section increases after 6 weeks of protocol adherence.

Progressive Tendon Loading Programme

The off-season loading programme targets the three most vulnerable triathlon tendons: Achilles, patellar, and rotator cuff. Each follows a 3-phase progression from isometric holds (weeks 1–2), to heavy slow resistance (weeks 3–5), to sport-specific loading (weeks 6–8).

• Achilles tendon — Weeks 1–2: Single-leg isometric calf raise holds. 5 x 45-second holds at 70% of maximum voluntary contraction, 2-minute rest between holds. Perform on a step with heel drop below horizontal. Every 48 hours.
• Achilles tendon — Weeks 3–5: Heavy slow resistance heel raises. 4 x 6 reps with 3-second concentric, 3-second eccentric (6-second total rep). Add weight progressively (10–20 kg dumbbell or loaded backpack). Every 48–72 hours.
• Achilles tendon — Weeks 6–8: Plyometric loading. Double-leg hops → single-leg hops → depth jumps (20 cm). 3 x 8 reps, 60–100 total ground contacts per session. Every 72 hours.
• Patellar tendon: Same progression using Spanish squat (isometric) → single-leg decline squat (heavy slow) → box jumps/split jumps (plyometric).
• Rotator cuff: Band external rotation holds (isometric) → cable external rotation 3x10 (slow eccentric) → medicine ball throws (sport-specific).

Maintaining Aerobic Base Through Cross-Training

Complete rest during the off-season causes measurable aerobic detraining within 2–3 weeks: VO2max declines by 5–10%, blood volume contracts, and mitochondrial density decreases. The off-season goal is to maintain 70–80% of peak aerobic fitness using low-impact cross-training that allows tendon recovery while keeping the cardiovascular engine running.

• Swimming: 2–3 sessions/week, 30–45 min at Z2. Focus on technique drills rather than yardage. Swimming is ideal off-season training because it loads no lower-body tendons.
• Cycling: 2–3 sessions/week, 45–90 min at Z2. Indoor trainer or outdoor — keep cadence above 85 rpm to minimise patellar tendon strain. One session can include 10–15 min of sweet-spot work (88–93% FTP) to maintain threshold capacity.
• Running: 1–2 sessions/week maximum during weeks 1–4 (the tendon rebuild phase). Increase to 2–3 sessions/week in weeks 5–8 as tendon loading progresses to plyometric phase. All runs at Z1–Z2 pace on soft surfaces when possible.
• Total weekly volume: 50–70% of peak season volume. Enough to prevent detraining; not enough to impede tendon recovery.

8-Week Off-Season Periodization Template

This template integrates tendon loading, aerobic maintenance, and recovery into a structured 8-week plan:

• Weeks 1–2 (Restoration): 3 tendon isometric sessions, 3 Z2 cross-train sessions (swim/bike only), 1 easy run. Total: 5–7 hrs/week.
• Weeks 3–4 (Rebuild): 3 heavy slow resistance sessions, 4 Z2 sessions (add 1 run), 1 technique swim. Total: 7–9 hrs/week.
• Weeks 5–6 (Load): 2 plyometric + 1 strength session, 5 Z2 sessions (2 runs, 2 bikes, 1 swim). Total: 8–11 hrs/week.
• Weeks 7–8 (Transition): 2 plyometric sessions, 6 structured sessions approaching normal distribution. Introduce 1 threshold session. Total: 10–13 hrs/week.

Building tendon resilience during the off-season is the single highest-return investment a triathlete can make for the following year. For collagen-supporting nutrition strategies and recovery protocols, explore our collagen and joint health guide and plan your return-to-training nutrition with the NorthLine Performance Planner.