madman
Super Moderator
Abstract
Purpose Several supplements are purported to promote muscle hypertrophy and strength gains in healthy subjects, or to prevent muscle wasting in atrophying situations (e.g., ageing or disuse periods). However, their effectiveness remains unclear.
Methods This review summarizes the available evidence on the beneficial impacts of several popular supplements on muscle mass or strength.
Results Among the supplements tested, nitrate and caffeine returned sufficient evidence supporting their acute beneficial effects on muscle strength, whereas the long-term consumption of creatine, protein and polyunsaturated fatty acids seems to consistently increase or preserve muscle mass and strength (evidence level A). On the other hand, mixed or unclear evidence was found for several popular supplements including branched-chain amino acids, adenosine triphosphate, citrulline, β-Hydroxy-β-methylbutyrate, minerals, most vitamins, phosphatidic acid or arginine (evidence level B), weak or scarce evidence was found for conjugated linoleic acid, glutamine, resveratrol, tribulus terrestris or ursolic acid (evidence level C), and no evidence was found for other supplements such as ornithine or α-ketoglutarate (evidence D). Of note, although most supplements appear to be safe when consumed at typical doses, some adverse events have been reported for some of them (e.g., caffeine, vitamins, α-ketoglutarate, tribulus terrestris, arginine) after large intakes, and there is insufficient evidence to determine the safety of many frequently used supplements (e.g., ornithine, conjugated linoleic acid, ursolic acid). Conclusion In summary, despite their popularity, there is little evidence supporting the use of most supplements, and some of them have been even proven ineffective or potentially associated with adverse effects.
Conclusion
A great variety of supplements have been purported to provide benefits for strength and muscle mass. However, of all the supplements analyzed, only nitrate and caffeine seem to consistently lead to acute muscle strength gains. When taken over longer periods, only creatine, protein and PUFAs have provided strong evidence supporting their capacity to improve or preserve muscle mass or strength. Nevertheless, their effects could depend on doses (e.g., a linear relationship between protein intake and LBM gains has been observed up to a maximum of 1.6 g/kg/day), type (e.g., not all protein or creatine supplements forms [WP versus other forms of protein, or CM versus other forms of creatine] provide the same benefits), and on the individual’s physiological status (e.g., higher protein doses are required in elderly people or athletes) (Table 1). Despite their popularity, most of the supplements available on the market lack scientific support for their alleged effects and some have even proved ineffective or have been found to give rise to serious adverse effects. Although some supplements have shown promising results in the basic research field, their effects in humans have not been consistently analyzed in the scientific literature (Tables 2 and 3). These findings could have important economic and practical implications, as the use of supplements should be avoided until there is sufficient scientifically backed evidence of their benefits. There is a clear need for studies designed to examine the effectiveness of supplements in terms of improving muscle mass and strength gains in healthy subjects or attenuating muscle wasting during catabolic states such as those produced in situations of ageing, injury or inactivity.
Purpose Several supplements are purported to promote muscle hypertrophy and strength gains in healthy subjects, or to prevent muscle wasting in atrophying situations (e.g., ageing or disuse periods). However, their effectiveness remains unclear.
Methods This review summarizes the available evidence on the beneficial impacts of several popular supplements on muscle mass or strength.
Results Among the supplements tested, nitrate and caffeine returned sufficient evidence supporting their acute beneficial effects on muscle strength, whereas the long-term consumption of creatine, protein and polyunsaturated fatty acids seems to consistently increase or preserve muscle mass and strength (evidence level A). On the other hand, mixed or unclear evidence was found for several popular supplements including branched-chain amino acids, adenosine triphosphate, citrulline, β-Hydroxy-β-methylbutyrate, minerals, most vitamins, phosphatidic acid or arginine (evidence level B), weak or scarce evidence was found for conjugated linoleic acid, glutamine, resveratrol, tribulus terrestris or ursolic acid (evidence level C), and no evidence was found for other supplements such as ornithine or α-ketoglutarate (evidence D). Of note, although most supplements appear to be safe when consumed at typical doses, some adverse events have been reported for some of them (e.g., caffeine, vitamins, α-ketoglutarate, tribulus terrestris, arginine) after large intakes, and there is insufficient evidence to determine the safety of many frequently used supplements (e.g., ornithine, conjugated linoleic acid, ursolic acid). Conclusion In summary, despite their popularity, there is little evidence supporting the use of most supplements, and some of them have been even proven ineffective or potentially associated with adverse effects.
Conclusion
A great variety of supplements have been purported to provide benefits for strength and muscle mass. However, of all the supplements analyzed, only nitrate and caffeine seem to consistently lead to acute muscle strength gains. When taken over longer periods, only creatine, protein and PUFAs have provided strong evidence supporting their capacity to improve or preserve muscle mass or strength. Nevertheless, their effects could depend on doses (e.g., a linear relationship between protein intake and LBM gains has been observed up to a maximum of 1.6 g/kg/day), type (e.g., not all protein or creatine supplements forms [WP versus other forms of protein, or CM versus other forms of creatine] provide the same benefits), and on the individual’s physiological status (e.g., higher protein doses are required in elderly people or athletes) (Table 1). Despite their popularity, most of the supplements available on the market lack scientific support for their alleged effects and some have even proved ineffective or have been found to give rise to serious adverse effects. Although some supplements have shown promising results in the basic research field, their effects in humans have not been consistently analyzed in the scientific literature (Tables 2 and 3). These findings could have important economic and practical implications, as the use of supplements should be avoided until there is sufficient scientifically backed evidence of their benefits. There is a clear need for studies designed to examine the effectiveness of supplements in terms of improving muscle mass and strength gains in healthy subjects or attenuating muscle wasting during catabolic states such as those produced in situations of ageing, injury or inactivity.
