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Novel Insights on Nutrient Management of Sarcopenia in Elderly
Published in Chad Cox, Clinical Nutrition and Aging, 2017
Mariangela Rondanelli, Milena Faliva, Francesca Monteferrario, Gabriella Peroni, Erica Repaci, Francesca Allieri, Simone Perna
Beta-hydroxy-beta-methylbutyrate (HMB) is a product of leucine metabolism that has been shown to slow protein breakdown in muscle tissue [48]. HMB may be effective at limiting the demands placed on the elderly subjects by acute stresses, such as sudden increases in physical activity, an immunologic challenge, or acute malnutrition [48, 49].
β-Hydroxy β-methylbutyrate (HMB)
Published in Linda M. Castell, Samantha J. Stear (Nottingham), Louise M. Burke, Nutritional Supplements in Sport, Exercise and Health, 2015
HMB is a metabolite of the essential branched chain amino acid leucine (LEU), the amino acid with the greatest ability to stimulate protein synthesis. Approximately 2–10% of LEU oxidation proceeds to HMB. Initial research on HMB focused on animals, assessing effects on immune function, morbidity/mortality, colostral milk fat content, growth rates, safety and toxicity. Despite unconvincing results in animal research, HMB supplementation was promoted to humans in the mid 1990s presuming that it might enhance gains in muscle size and strength while reducing muscle damage and soreness associated with resistance training (Nissen et al., 1996), and possibly enhance aerobic capacity.
ß-hydroxy-ß-methylbutyrate
Published in Jay R Hoffman, Dietary Supplementation in Sport and Exercise, 2019
β-hydroxy-β-methylbutyrate (HMB) is a metabolite of leucine, a branched chained amino acid which functions as an effective stimulator of muscle protein synthesis (MPS). While Russian chemists originally reported the chemical synthesis of HMB in 1877 (46), the first documentation of HMB in humans was in 1968 from a patient with isovaleric acidemia, a condition that disrupts leucine metabolism (69). Commercially, HMB became available in the late 1990s and was primarily marketed to athletes and exercising individuals. Over the past 20 years, our understanding of this nutrient has increased immensely as hundreds of articles have been published investigating the mechanistic and applied effects of HMB across a variety of populations. However, the story of HMB begins with the initial work done by Steve Nissen’s group at the University of Iowa aimed at improving the quality and quantity of meat produced from domestic animals. Their early manuscripts revealed that seven weeks of HMB feeding in broiler chickens resulted in a faster growth rate, reduction in mortality and increased muscle yield (50). Subsequent findings showed positive results as HMB decreased morbidity by 40% and mortality by 50% in young calves undergoing physiological stress from being transported cross-country (76), as well as increased milk fat percentage and weanling pig weight (49). From this initial animal work, it appeared that HMB possessed unique effects on promoting the retention and growth of lean mass while providing support to the immune system. The first human study by Nissen et al. (52) suggested that HMB exerts both anabolic and anti-catabolic effects which drew attention from athletes and clinicians as a means to augment and/or preserve muscle mass alone or in conjunction with training. In this chapter, we will begin by exploring the proposed mechanisms of action for HMB raging from its effect on intramuscular signalling to its immunomodulatory properties. In relation, we will also compare common formulations of this compound along with effective dosing strategies. With this foundation laid, we will discuss the effects of acute supplementation with HMB and its influence on markers of muscle damage, immune cells, physical function and recovery from strenuous muscular exertion. Further, and perhaps most importantly, we will uncover the effects of HMB on chronic adaptations to resistance, anaerobic and endurance training. While HMB has gained popularity primarily in the athletic realm, we will review its efficacy in relation the clinical populations such as those with sarcopenia, cachexia and other chronic conditions. Finally, this chapter concludes with a discussion of the safety and legality of HMB for various populations and application in sport.
Low Dose of β-Hydroxy-β-Methylbutyrate (HMB) Alleviates Muscle Strength Loss and Limited Joint Flexibility following Eccentric Contractions
Published in Journal of the American College of Nutrition, 2021
Yosuke Tsuchiya, Hisashi Ueda, Naoki Sugita, Eisuke Ochi
β-hydroxy-b-methylbutyrate (HMB), a metabolite of a-ketocisocaproate (KIC) and the amino acid leucine, is a nutritional supplement originally used to increase muscle mass and reduce subcutaneous fat in livestock (5). Leucine is first metabolized by enzymes in the body into KIC, which is subsequently metabolized into isovaleryl-CoA and HMB (6). Finally, approximately 5% of leucine becomes HMB. It assumes that HMB increases dynamic strength (7), fat-free weight (8), activation of muscle protein synthesis signals (7,9,10), inhibition of proteolysis (7,11), and a positive effect on increasing aerobic and anaerobic capacity (12). In addition, HMB is thought to activate muscle satellite cells and increase the capacity of muscle regeneration (11,13). However, there is no consensus on the effects of HMB supplementation on muscle damage following exercise in a short time frame. We recently studied the effects of 2- and 4-week HMB supplementation (3 g/day) on ECC-induced muscle damage; both the 2- and 4-week treatments decreased muscle strength reduction, ROM, and muscle swelling and increased muscle stiffness (14). Therefore, HMB has positive effects on exercise performance and discomfort following temporal exercise.
Cognitive function is preserved in aged mice following long-term β-hydroxy β-methylbutyrate supplementation
Published in Nutritional Neuroscience, 2020
Michael Munroe, Ziad S. Mahmassani, Svyatoslav Dvoretskiy, Justin J. Reid, Benjamin F. Miller, Karyn Hamilton, Justin S. Rhodes, Marni D. Boppart
β-Hydroxy β-methylbutyrate (HMB) is a leucine metabolite frequently used as a nutritional supplement to enhance the beneficial physical adaptations associated with exercise training. Increases in lean mass and muscle strength, as well as protection from muscle damage post-exercise, have been observed with HMB supplementation in young individuals beginning a resistance exercise training program.11–13 Older adults and individuals with disease also benefit from HMB supplementation, as improvements in body composition and strength have been observed, particularly after long-term use in conjunction with exercise.14–17 Recent rodent studies have expanded the potential benefits of HMB supplementation to include maintenance of cognitive function with age. Improvements to working memory and visuospatial learning have been observed in aged rats following long-term HMB supplementation.18,19 These results are promising, yet the specific mechanisms underlying such benefits are not known. In addition, the ability for HMB to concomitantly preserve both muscle mass and cognitive function from middle age to end of life has not been tested.
Two and Four Weeks of β-Hydroxy-β-Methylbutyrate (HMB) Supplementations Reduce Muscle Damage Following Eccentric Contractions
Published in Journal of the American College of Nutrition, 2019
Yosuke Tsuchiya, Kinjiro Hirayama, Hisashi Ueda, Eisuke Ochi
This study investigated the effects of 2 and 4 weeks of HMB supplementation on muscle damage induced after transient ECCs. The decreased muscle strength, restricted ROM, muscle swelling, and increased muscle stiffness seen after ECCs were inhibited in the supplemental groups. These findings support the hypothesis of this study. Conversely, there was no difference between the 2 and 4 weeks of supplementation, which rejected our hypothesis. Based on our results, HMB may be a useful ergogenic aid for maintaining muscle performance. Importantly, since previous study has demonstrated that the single HMB supplementation for 6 days did not cause a beneficial effect on the muscle damage (19), the supplemental period should set more than 2 weeks to obtain these phenomena.