The Claim

In older women undergoing 12 weeks of resistance training, a daily protein intake of 1.4 g/kg/d from lean beef or mixed sources prevents a reduction in distal patellar tendon cross-sectional area, while a daily protein intake of 0.8 g/kg/d is associated with a significant decrease in distal patellar tendon cross-sectional area.

Source: Greater Protein Intake Emphasizing Lean Beef Does Not Affect Resistance Training-Induced Adaptations in Skeletal Muscle and Tendon of Older Women: A Randomized Controlled Feeding Trial

What the research says

Supports is higher

Support is ahead, but a single strong opposing study can change this.

Supports
69score
Challenges
0score

These are independent scores, not a percentage. Higher-grade studies count more, so a single strong opposing study can outweigh several weaker ones.

Cause and effect
1 study reviewed
In plain English

In older women doing resistance training for 12 weeks, consuming 1.4 grams of protein per kilogram of body weight daily maintains the thickness of the tendon below the kneecap, while consuming 0.8 grams per kilogram daily results in a measurable thinning of this tendon.

See the scientific wording

In older women undergoing 12 weeks of resistance training, higher daily protein intake (1.4 g/kg/d) from lean beef or mixed sources prevents a reduction in distal patellar tendon cross-sectional area, whereas intake at the recommended level (0.8 g/kg/d) is associated with a significant decrease in this region, suggesting protein may help maintain tendon structure in this specific location.

Why this might work

When older women lift weights, the tendons in their knees experience tension that triggers cells in the tendon to make more collagen. If they eat more protein rich in glycine and proline, those amino acids become more available around the tendon, allowing the cells to produce even more collagen, which keeps the tendon from getting thinner.

Supported mechanismbased on 1 study

What the research says

1 study

  1. Study: Greater Protein Intake Emphasizing Lean Beef Does Not Affect Resistance Training-Induced Adaptations in Skeletal Muscle and Tendon of Older Women: A Randomized Controlled Feeding Trial

    When older women did strength training, those who ate the usual amount of protein saw their knee tendon get slightly thinner, but those who ate more protein — even from beef — kept their tendon the same size. So more protein helped stop the thinning.

Score breakdown, mechanism chain, raw evidence, ideal studies needed & 1 supporting studies

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