Pea Protein vs. Whey Protein: Which Helps Muscles After Exercise?

observational-study PMID: 36678213

Quick Summary: A recent study looked at how pea protein and whey protein affect muscle recovery in older adults after long walks. The research found that whey protein helped reduce muscle damage, while pea protein didn't show the same benefit.

Does Pea Protein Help Muscles Recover?

This study compared pea protein and whey protein to see how they affect muscle damage after exercise. The researchers measured levels of certain substances in the blood that indicate muscle damage. They found that whey protein helped reduce these levels, suggesting it aided in muscle recovery. Pea protein, however, didn't have the same effect.

Study Details

Who was studied: 47 active adults over 60 years old.

How long: The participants took the supplements for 13 days.

What they took: Participants were split into three groups:

Whey protein (25 grams per day)
Pea protein (25 grams per day)
A placebo (a substance with no active effect)

All groups then went for a long walk (20-30 km). Researchers measured muscle damage before and after the walk.

What This Means For You

If you're an older adult who exercises: If you're looking to reduce muscle soreness and damage after long walks or similar activities, whey protein might be a better choice than pea protein, based on this study.

Pea protein for general health: Pea protein is still a good source of protein and can be part of a healthy diet. This study doesn't mean pea protein is "bad," just that it didn't show the same muscle-recovery benefits in this specific situation.

Consider your goals: If your main goal is muscle recovery after endurance exercise, whey protein might be worth considering. If you have dietary restrictions or preferences, pea protein can still be a good option for overall protein intake.

Study Limitations

Small group: The study only included a small number of people, so the results might not apply to everyone.

Specific exercise: The study focused on long-distance walking. The results might be different for other types of exercise, like weightlifting.

Older adults only: The study only looked at older adults. The results might be different for younger people.

Other factors: The study didn't control for everything, like what people ate or how active they were outside of the study.

Key Findings

The study found that 13 days of whey protein supplementation (25 g/day) significantly reduced exercise-induced muscle damage (EIMD) in older adults, as evidenced by lower creatine kinase (CK) levels 24 hours post-exercise compared to pea protein and placebo. Pea protein supplementation did not differ from placebo in CK, lactate dehydrogenase (LDH), muscle strength, soreness, or skeletal muscle mass (all p > 0.05).

Study Design

This was a randomized, placebo-controlled observational study involving 47 physically active adults aged ≥60 years. Participants were divided into three groups: whey protein (n=15), pea protein (n=15), or iso-caloric placebo (n=15). After 13 days of supplementation, all underwent a single prolonged walking bout (20–30 km). Blood biomarkers (CK, LDH), muscle strength (isokinetic knee extension), skeletal muscle mass (bioelectrical impedance), and soreness (visual analog scale) were assessed pre-exercise and at 24h, 48h, and 72h post-exercise.

Dosage & Administration

Participants consumed 25 g/day of either whey protein isolate (WPI) or pea protein isolate (PPI) in powder form, mixed with water or milk, for 13 consecutive days. The placebo group received 25 g/day of iso-caloric maltodextrin. Supplementation timing or co-ingestion with meals was not specified.

Results & Efficacy

CK levels: Whey protein reduced CK by 42% at 24h post-exercise (175 ± 90 U/L) compared to pea protein (300 ± 309 U/L, p < 0.001) and placebo (330 ± 165 U/L, p < 0.001). No differences were observed between pea and placebo (p = 0.89).
LDH levels: No significant differences across groups at any timepoint (p > 0.05).
Muscle strength: No changes in isokinetic knee extension torque (p > 0.05).
Muscle soreness: No group differences (p > 0.05).
Skeletal muscle mass: No significant changes (p > 0.05).

Limitations

Small sample size: Only 15 participants per group after dropouts, limiting statistical power.
Observational design: May introduce confounding variables (e.g., dietary intake, activity levels) not fully controlled.
Single-exercise bout: Findings may not generalize to chronic exercise or other modalities (e.g., resistance training).
Protein quality: Whey’s higher leucine content and faster absorption rate could explain superior efficacy, but this was not directly measured.
Population specificity: Results apply only to active older adults; effects in sedentary individuals or younger populations remain unclear.

Clinical Relevance

For older adults engaging in endurance activities like long-distance walking, whey protein may offer protective benefits against acute muscle damage, as indicated by reduced CK levels. Pea protein (25 g/day) did not demonstrate similar efficacy in this context, suggesting it may not be optimal for mitigating EIMD in aging populations. However, the lack of differences in muscle strength, soreness, and mass highlights the need for further research on pea protein’s role in muscle recovery. Practically, older athletes or exercisers prioritizing muscle damage reduction might prefer whey protein, while pea protein could still be considered for general protein intake needs. Future studies should explore higher pea protein doses, combination with other plant-based proteins, or longer-term supplementation effects.

Source: PubMed (2023)