by Reed Mangels, PhD, RD
Have you ever felt sore the day after a vigorous workout? If you have, you’ve experienced exercise-induced muscle damage. This is the technical name for the muscle soreness and stiffness that you feel after unfamiliar or more intense exercise. Some of the symptoms can last for several days and muscle soreness may take 5-7 days to resolve. Exercise-induced muscle damage can temporarily have a negative effect on performance by reducing strength and speed. Protein plays a role in muscle recovery after exercise. While the Recommended Dietary Allowance (RDA) for protein is no higher for athletes than for non-athletes, many experts recommend that athletes get between 1.2 and 2.0 grams of protein per kilogram body weight (0.55 to 0.91 grams of protein per pound of body weight).
What is the study?
Researchers wondered if vegetarian athletes would recover faster if they consumed the higher amount (2.0 g/kg) of protein compared to the lower amount (1.2 g/kg). In order to examine this question, sixteen individuals (9 males and 7 females) with an average age of 24 years were studied. All study subjects had followed a vegetarian diet for at least 3 months before the study started. They could eat eggs and dairy products. The subjects kept a record of what they ate for 3 days before the study started. Their baseline protein intake was calculated using these records and the subjects were given unflavored pea protein isolate to add to their diet so that they were getting either 1.2 or 2.0 g/kg/day of protein.
Subjects were randomly assigned to consume either 1.2 or 2.0 g/kg/day of protein for 5 days, eat their usual diet for 2 weeks, and then switch to the other protein level for 5 days. At the beginning of the time that the subjects were eating a measured amount of protein, they completed a muscle damage protocol in which they did controlled exercise that led to muscle soreness and stiffness. They reported the degree of muscle soreness they experienced and did various tests to measure strength and power both before and for 5 days after they completed the muscle damage protocol.
What did this study find?
There was no difference in recovery of strength and power or of recovery from soreness in people following a vegetarian diet who consumed the lower (1.2 g/kg) or upper (2.0 g/kg) ends of protein recommendations for athletes. These results suggest that vegetarian athletes do not need to consume extra protein above the lower end of the protein recommendation for athletes to successfully recover from exercise-induced muscle damage.
Reference:
Presti N, Rideout TC, Temple JL, et al. Recovery of strength after exercise-induced muscle damage in vegetarians consuming the upper and lower ends of protein recommendations for athletes. Nutrients. 2025;17:1046.
More VRG articles for Vegan and Vegetarian Athletes are available here.