Nutrition

Protein Intake and Recovery from Muscle Soreness

How dietary protein supports muscle repair after exercise, what research says about DOMS and strength recovery, and which other nutrients may help.

Date 06.11.2025

Author

maq

Topics

What is muscle soreness (DOMS), really?

Muscle soreness, scientifically known as delayed-onset muscle soreness (DOMS), is that feeling of discomfort or stiffness that appears between 24 and 48 hours after an effort to which the muscle is not accustomed.
For years it was believed that it was caused by the crystallization of lactic acid, but today we know that this is not true: lactate does not crystallize at physiological pH.

The most widely accepted cause today is microscopic damage to muscle fibers (micro-tears), especially after eccentric contractions such as going down stairs, slowing down a stride or cushioning a descent.
This damage triggers inflammatory processes and oxidative stress, which explains the pain and temporary loss of strength.

Why is protein important in recovery?

Because muscles repair themselves using amino acids from protein. After exercise, the body activates muscle protein synthesis to regenerate damaged tissue.
An adequate intake of protein – either through diet or supplements – promotes this repair, helping to recover strength and performance sooner.

Can protein supplementation reduce muscle soreness?

Scientific evidence shows nuances.
A recent meta-analysis that looked at 29 studies found that protein consumption before or after exercise does not significantly reduce the sensation of pain, but it does improve muscle strength recovery and reduces blood levels of creatine kinase (CK), a marker of muscle damage.

In other words, although it does not prevent you from feeling soreness, it can help you perform better in the following days.

What if I already eat enough protein a day?

In that case, adding more protein doesn't always bring additional benefits.
For example, a study in runners who ran a 15 km race found no difference between taking protein or carbohydrates if the participants' diet already covered daily needs (at least 1,1 g/kg of body weight).
The conclusion is clear: quality and daily distribution are just as important as quantity.

What other nutrients can help?

In addition to protein, stiffness is associated with inflammatory processes and oxidative stress. For this reason, certain micronutrients with antioxidant function can contribute at specific times, especially after very demanding workouts.

A meta-analysis that reviewed 18 studies on vitamins C and E showed that their combination can reduce oxidative stress, inflammation (e.g., interleukin 6), and muscle damage (as measured by CK).
However, no clear improvements in perceived strength or pain were observed.
Ideally, you should maintain an adequate consumption of fruits and vegetables on a daily basis, and reserve supplementation only for specific contexts.

What can I do to prevent or reduce muscle soreness?

Some practical tips:

Avoid making sudden changes in training (especially intense eccentric exercises) right before a race or important week.
Maintain an adequate and well-distributed protein intake throughout the day.
Get plenty of rest and sleep, as muscle regeneration occurs mostly during sleep.
Hydrate well and do not neglect the intake of carbohydrates after intense workouts.
After particularly hard sessions, a diet rich in natural antioxidants (berries, kiwi, citrus fruits, green leafy vegetables) can be helpful.

In summary

Soreness is a natural consequence of training, the result of muscle micro-tears, inflammation and oxidative stress.
Protein plays a key role in muscle repair and strength recovery, although it does not always reduce pain.
When the diet is already adequate, it is not necessary to add more protein, but a balanced diet, with enough energy, protein and natural antioxidants, will be your best strategy to minimize its impact.

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