Protein supplementation and weight gain
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Protein Supplementation and Weight Gain: Effects on Muscle Mass, Strength, and Body Composition
Protein Supplementation and Resistance Training: Muscle Mass and Strength Gains
Multiple studies show that protein supplementation significantly increases muscle mass and strength when combined with resistance exercise training in healthy adults, older adults, and frail elderly people. These benefits include greater gains in fat-free mass (FFM), muscle size, and one-repetition maximum strength compared to resistance training alone 13610. The effect is more pronounced in resistance-trained individuals and diminishes with age, but remains beneficial for both younger and older populations 1310. In frail elderly people, protein supplementation is necessary to achieve muscle mass gains during exercise training, although improvements in strength and physical performance can occur with exercise alone .
Protein Supplementation in Older Adults: Lean Body Mass and Physical Function
In older adults, especially those with low habitual protein intake, daily protein supplementation leads to increases in lean body mass and improvements in muscle strength and physical performance 57810. Supplementing protein at breakfast and lunch, the meals typically lower in protein, has been shown to increase whole-body lean tissue mass, particularly in the limbs . These effects are observed in both physically active and frail older adults, suggesting that optimizing protein intake throughout the day can help preserve muscle mass during aging 78.
Protein Supplementation and Endurance Training: Body Composition and Performance
Protein supplementation during endurance training also results in greater lean mass gain, improved aerobic capacity, and better exercise performance compared to endurance training alone . This suggests that protein supplementation is not only beneficial for resistance training but also supports adaptations to endurance exercise, enhancing both body composition and physical performance .
Protein Supplementation After Bariatric Surgery: Weight and Body Composition
In patients who have undergone metabolic bariatric surgery, protein supplementation leads to greater reductions in weight and fat mass, and increases in muscle mass and fat-free mass compared to controls. However, it does not significantly affect BMI or lean body mass, indicating that while protein supplementation can improve some aspects of body composition, its effects on overall body weight metrics may be limited in this population .
High Protein Intake and Long-Term Weight Gain
While protein supplementation is effective for increasing muscle mass and strength, especially when combined with exercise, high dietary protein intake over the long term has been associated with an increased risk of body weight gain and higher all-cause mortality in populations at high cardiovascular risk. This risk is particularly notable when protein replaces carbohydrates in the diet, and is more pronounced with higher animal protein consumption .
Conclusion
Protein supplementation is a proven strategy to enhance muscle mass, strength, and lean body mass, especially when combined with resistance or endurance training. These benefits are seen across age groups, including older and frail adults, and in specific populations such as those recovering from bariatric surgery. However, excessive long-term protein intake, particularly from animal sources, may increase the risk of weight gain and adverse health outcomes in certain populations. For most people, optimizing protein intake—especially in combination with exercise—can support healthy body composition and physical function, but moderation and balance remain important.
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