# Tendons and ligaments under load: what collagen does in a training context

> The core of the Achilles tendon is barely renewed after the age of seventeen. What that means for connective tissue in training - and why the window before a session has been studied.

Tendons and ligaments carry a lot of load in training and get very little attention. They are less well perfused than muscle and respond markedly more slowly to stimuli.

## Tendons are slow tissue

Heinemeier et al. (2013) used carbon-14 from the atmospheric nuclear tests of the 1950s as a time marker in tissue. The result: the core of the Achilles tendon consists essentially of collagen formed up to around the age of seventeen. After that, practically no remodelling takes place in the tendon core. Turnover happens mainly in the outer layers - and there it depends on mechanical loading. Thinking in weeks with tendons is thinking too short; the timescale is months.

## Mechanical load is the primary signal

Tenocytes are mechanosensitive: they translate tension into biochemical signals. After a loading session, collagen synthesis in peritendinous tissue rises measurably, peaking roughly 24 to 72 hours later - but degradation rises at the same time. Whether anything is added on balance depends on the ratio of stimulus to recovery (Magnusson, Langberg & Kjaer 2010). For nutrition that means: substrate without a training stimulus stays substrate.

## The window before the session

Shaw et al. (2017) investigated exactly this sequence: gelatin with vitamin C, taken one hour before six minutes of rope skipping. In the higher-dose group, blood PINP - a marker of collagen formation - doubled. Lis and Baar (2019) then compared different collagen sources and doses and found markedly higher availability of relevant amino acids in blood at 15 g than at 5 g.

From this a sober practical rule follows: the serving 30 to 60 minutes before the session, together with vitamin C.

## What has been studied in tendon complaints

In a small randomised trial on Achilles tendinopathy, Praet et al. (2019) combined specific collagen peptides with calf-strengthening exercise. The combination performed better functionally than exercise alone. The caveats belong with it: small sample, short period, a single peptide preparation. EFSA has approved no health claim for collagen as such. Vitamin C, by contrast, demonstrably contributes to normal collagen formation.

## How WOO® Kollagen Pfirsich is set up in the sachet box

**[WOO® Kollagen Pfirsich](/en/shop/woo-collagen-peach-box)** consists of 85% collagen hydrolysate and 13% collagen tripeptides from bovine sources, plus peach flavouring, 2% mango fruit powder with the Careflow® extract, citric acid and steviol glycosides as sweetener. A 15 g serving comes to under 0.5 g of carbohydrate, 13 g of protein and 53 kcal - a composition that does not sit in the stomach before a session.

The box holds 30 individual sachets. One sachet goes into the gym bag and gets stirred into 200 ml of water on the way. Vitamin C is not included - **[WOO® Beauty Caps](/en/shop/woo-beauty-caps-can)** or a vitamin C source from the meal fill that gap. Not suitable for vegans and vegetarians.

## Frequently asked questions

**How long until something changes in a tendon?**
Connective tissue adapts over months. Studies with functional endpoints typically run three to six months.

**Why vitamin C with it?**
Hydroxylation of proline in the collagen molecule is vitamin C dependent.

**Drinking it right before training - does that sit well?**
At 53 kcal and virtually no carbohydrate the serving is light; a 30 to 60 minute lead time is unproblematic for most people.

## Sources

Heinemeier KM et al. (2013), FASEB Journal - Lack of tissue renewal in human adult Achilles tendon is revealed by nuclear bomb 14C.
Magnusson SP, Langberg H & Kjaer M (2010), Nature Reviews Rheumatology - The pathogenesis of tendinopathy: balancing the response to loading.
Shaw G et al. (2017), American Journal of Clinical Nutrition - Vitamin C-enriched gelatin supplementation before intermittent activity augments collagen synthesis.
Lis DM & Baar K (2019), Journal of Strength and Conditioning Research - Effects of different vitamin C-enriched collagen derivatives on collagen synthesis.
Praet SFE et al. (2019), Nutrients - Oral supplementation of specific collagen peptides combined with calf-strengthening exercises in Achilles tendinopathy.

*WOO® Kollagen Pfirsich in the sachet box - in the NEMAPO shop.*