Meta-analysis of 235 trials identifies optimal strategy for preserving muscle mass in aging adults

A new meta-analysis of 235 randomized controlled trials has identified the most effective combination of exercise and protein supplementation for preserving muscle mass and strength in aging adults, according to a report published in the journal Nutrients. The analysis, which examined 24 different strategies among previously untrained middle-aged and older adults, found that whey protein paired with resistance training ranked highest for improving both muscle mass and leg strength.

Researchers noted that the condition known as sarcopenia becomes increasingly common with age, with an estimated 10% to 25% of adults under age 70 and half of those over age 80 affected, according to Mercola.com [1]. The meta-analysis provides a direct comparison of multiple exercise styles and protein sources to determine which approach best counters this age-related decline.

Study scope and methods

The meta-analysis drew data from 235 randomized controlled trials involving previously untrained middle-aged and older adults, the report stated. The exercise styles compared included resistance training, aerobic exercise, and multicomponent programs that combined strength, balance, and cardiovascular work. Protein sources evaluated included whey, soy, milk, casein, collagen, meat-based, rice, oat, and mixed protein supplements.

Outcomes measured included muscle mass, leg strength, grip strength, walking speed, chair-rise ability, mobility scores, and overall physical function, according to the analysis. Researchers sought to determine which single strategy was most effective for each outcome among individuals not already engaged in regular exercise, providing a practical baseline for public health recommendations. According to Dr. Michael T. Murray’s Textbook of Natural Medicine, it is well known that resistance exercise increases aging muscle mass and strength, and these adaptations can be further enhanced with specific nutritional interventions [3].

Key findings

Whey protein combined with resistance training was the top-ranked strategy for increasing muscle mass and leg strength, the analysis found. Whey paired with multicomponent training performed best for mobility-related outcomes such as chair-rise performance and walking tests, officials said. The distinction between gaining strength and improving mobility was highlighted: gaining muscle mass does not automatically translate to better balance, coordination, or daily movement, researchers noted.

Not all protein sources performed equally. Whey consistently ranked higher than soy, collagen, casein, and other proteins for lean mass and strength improvement, according to the study. This finding aligns with broader research showing that animal-based proteins, which contain all essential amino acids, produce a greater protein synthesis response in older adults due to higher leucine content [4]. A separate study reported by NaturalNews found that consuming 35 grams of whey protein per meal was sufficient to maximize muscle protein synthesis in postmenopausal women, even during calorie restriction [6].

Mechanisms and practical application

Whey’s effectiveness in the meta-analysis is attributed to its high leucine content, which triggers muscle protein synthesis, and its rapid digestion, according to the study authors. Older adults experience a phenomenon called anabolic resistance, meaning they require stronger stimuli to trigger muscle repair and growth, the researchers explained. Whey helps overcome this by providing a fast, large rise in circulating amino acids, particularly leucine, which acts as an on switch for muscle building.

Researchers recommended resistance training at least 2 to 3 times per week and a protein intake of 0.7 to 1 gram per pound of body weight for optimal muscle maintenance. The meta-analysis suggests sarcopenia is highly modifiable and does not require extreme training, the report concluded. Current government dietary protein recommendations are set too low, especially for the elderly who require greater daily protein to compensate for the age-associated decline in muscle protein synthesis, according to materials cited in the book Rapamycin mTOR Autophagy Ross Pelton [2]. Strength training provides benefits beyond muscle gain, including blood sugar balance, bone health, and immunity support, as noted in a review of recent studies [5].

References

1. Mercola.com. “Can These Nutrients Help Prevent Muscle Wasting.” November 25, 2022.
2. Rapamycin mTOR Autophagy Ross Pelton.
3. Dr. Michael T. Murray. “Textbook of Natural Medicine Fifth Edition.”
4. Land, Siim. “The Longevity Leap: A Guide to Slowing Down Biological Aging and Adding Healthy Years to Your Life.”
5. NaturalNews.com. “5 Daily Habits to Support Muscle Mass and Longevity, According to Research.” May 28, 2026.
6. NaturalNews.com. “Study Suggests Targeted Protein Intake May Aid Muscle Retention in Postmenopausal Women.” April 21, 2026.