Protein supplements for weight gain
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Protein Supplements and Weight Gain: Muscle Mass and Strength
Research consistently shows that protein supplementation can help increase muscle mass and strength, especially when combined with resistance or endurance training in both younger and older adults1234+5 MORE. Protein supplements are particularly effective for those who may not get enough protein from their regular diet or who are engaged in regular exercise programs1279+1 MORE.
Protein Supplementation and Resistance Training
Multiple studies and meta-analyses have found that adding protein supplements to a resistance training program leads to greater gains in muscle mass (fat-free mass) and strength compared to training alone1245+2 MORE. The benefits are more pronounced in people who are already resistance-trained and in those who are older or frail, although the effect may decrease with age1245+2 MORE. For most adults, consuming more than about 1.6 grams of protein per kilogram of body weight per day does not provide additional muscle gain benefits.
Protein Supplements for Older Adults
Older adults, especially those over 60, can benefit from protein supplementation to support muscle mass and strength gains during resistance training2457+1 MORE. Milk-based protein supplements may be more effective than whey protein alone for increasing lean body mass in this age group. However, the overall effect is moderate, and the greatest benefit is seen in those who do not already consume enough protein in their diet59.
Protein Supplementation and Endurance Training
Protein supplements also help increase lean body mass and improve aerobic capacity when combined with endurance training38. These benefits are seen in both healthy and clinical populations, with protein supplementation leading to greater improvements in aerobic fitness and muscle mass compared to endurance training alone38.
Protein Supplements and General Weight Gain
While protein supplements can help increase lean body mass (muscle), they do not typically lead to significant increases in fat mass when used as part of a balanced diet and exercise program1238+2 MORE. The main effect is an increase in muscle, not overall body fat, making protein supplements a useful tool for healthy weight gain focused on muscle rather than fat1238+2 MORE.
Special Considerations: Pregnancy and Undernutrition
In specific populations, such as pregnant women in low- and middle-income countries, balanced energy and protein supplements can help increase healthy weight gain during pregnancy and reduce the risk of inadequate weight gain. Targeted supplementation is most effective for those with undernutrition or low body weight.
Conclusion
Protein supplements are effective for supporting weight gain through increased muscle mass and strength, especially when combined with resistance or endurance training. The benefits are most significant for those who do not get enough protein from their diet, older adults, and individuals engaged in regular exercise. For most people, consuming more than 1.6 grams of protein per kilogram of body weight per day does not provide extra benefits for muscle gain. Protein supplements are a safe and practical option for healthy weight gain focused on building muscle rather than fat1234+6 MORE.
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