Randomised trial · Nutrients · 2020Conflicts declared

Whey and pea protein after intense exercise in men

What it found

In 92 non-athletic men, whey protein taken for 5 days after a tough workout lowered blood markers of muscle damage compared with water.

Pea protein had a smaller, non-significant effect, and neither protein changed soreness or fitness test results.

What they found

Studies in people

Muscle damage markers

Whey protein significantly lowered blood levels of creatine kinase and myoglobin compared with water during the last 2 to 3 days of recovery. The effect was large. Pea protein had an intermediate, non-significant effect, and there was no significant difference between pea and whey protein.

Soreness and performance

Neither whey nor pea protein changed delayed onset muscle soreness or results on bench press, vertical jump, leg-back strength, or 30-second cycling tests compared with water.

Inflammation

The exercise caused a modest rise in C-reactive protein after 24 hours, but there were no significant differences between the protein and water groups.

Blood urea nitrogen

Blood urea nitrogen was higher during recovery in both protein groups, but levels did not reach clinically significant amounts.

Other findings

Amino acid difference

Pea protein has a lower leucine content than whey protein. The authors suggest this may partly explain why whey had a stronger effect on muscle damage markers.

What the authors conclude

“Taken together, these data support the strategy of using three 0.3 g/kg doses per day of whey protein isolate during several days of recovery from intensive eccentric-based exercise to reduce serum levels of muscle damage biomarkers in untrained males.”
Nieman DC, Zwetsloot KA, Simonson AJ, et al, 2020

Also in their conclusions

  • They conclude that taking three 0.3 g/kg doses of whey protein isolate per day during several days of recovery from intense eccentric exercise reduces serum levels of muscle damage biomarkers in untrained males.
  • They note that pea protein had an intermediate but non-significant effect compared to water, with no differences found between pea and whey proteins.
  • They suggest that future studies should consider using leucine-fortified pea protein isolate supplements or greater dose volumes to match the leucine and BCAA profile of whey protein isolate.

How it was done

Protein supplements are often used by athletes hoping to recover faster from intense exercise, but studies have not agreed on whether they actually reduce muscle damage and soreness. The authors wanted to compare pea protein, whey protein, and water directly.

They randomly assigned 92 non-athletic, non-obese men aged 18 to 55 to whey protein, pea protein, or water only. For 5 days after a 90-minute eccentric exercise session, the men took 0.9 g protein per kg of body weight per day, split into three doses, or water. Blood markers, soreness, and fitness tests were measured each morning.

What it can’t tell you

  • This trial was in non-athletic, non-obese men aged 18 to 55, so the results may not apply to women, athletes, or other age groups.
  • The study did not control or measure diet, so other foods eaten during the week could have influenced the results.
  • The trial lasted only 5 days, so it cannot show what happens with longer use.

The paper

Title
Effects of Whey and Pea Protein Supplementation on Post-Eccentric Exercise Muscle Damage: A Randomized Trial
Type
Randomised controlled trial
Evidence
Studies in people
Summarised from
Full text
Cite
Nieman DC, Zwetsloot KA, Simonson AJ, et al (2020). Effects of Whey and Pea Protein Supplementation on Post-Eccentric Exercise Muscle Damage: A Randomized Trial. Nutrients. doi:10.3390/nu12082382Free full textPubMed 32784847DOI

Summary written 26 Sep 2026. Check it against the paper before it changes what you eat. How we summarise papers · Report an error