HMB (or β-Hydroxy β-Methylbutyrate) is needed by the body to protect and repair muscle tissue. It is thought to do this by slowing muscle protein breakdown and speeding protein synthesis, and also by preserving the structural integrity of your muscle cells.
In athletes where muscle tissue is damaged (causing soreness), repaired and built more frequently through training it stands to reason that you need more HMB. Sure enough research has now shown that supplementing the diet with 3g HMB per day improves exercise performance. It has been shown to speed strength and muscle mass gains in strength athletes, and improve endurance performance in cyclists and runners.
HMB is one of the most researched supplement ingredients proven to improve athletic performance right behind Creatine Monohydrate. It was initially patented by Iowa State University however these patents expired in 2018. This has led to less control over the HMB supply and quality of HMB products.
This page is a full guide to how HMB works, the research backing it and who should be using it.
Where your body gets HMB from:
2.What will taking HMB do for you?
Reduces the recovery time needed between training sessions (16)
Found to have a number of health benefits such as reduced blood pressure and cholesterol level (18)
3.How does HMB work?
HMB works by slowing protein breakdown and speeding up protein synthesis in repair. HMB is also a vital structural component used to maintain the integrity of muscle cell membranes, preventing them from damage and supporting rebuild.
HMB is important in muscle health. It is stored in the muscles and used to build, maintain and repair muscle cells.
HMB is bound to Calcium to keep it stable as a powder and more soluble in water. Calcium is also good for bone health. Evidence from cancer studies suggests that HMB may inhibit the ubiquitin-proteasome proteolytic pathway, a series of chemical reactions that work to break down muscle protein (15).
This means you are less likely to lose muscle mass through damage or inactivity. HMB is also thought to stimulate the production of muscle protein to be used in the muscle adaptation process through a series of chemical process collectively called the m-TOR pathway.
Considering the way that HMB is thought to work, it is likely to be more beneficial to athletes that experience muscle damage and soreness on a regular basis. This is especially relevant for pre-season training, and constantly varied training methods such as CrossFit. Learn the benefits of HMB for CrossFit athletes here.
In endurance athletes this means that muscles rapidly change to become more energy efficient whereas in the strength athlete muscle cells will grow more quickly to generate more power. Overall, using HMB enhances your recovery from, and adaptation to all types of training. It is a product that can be used by all athletes that are training hard, and at high volume, regardless of their sporting event. Constantly varied functional fitness programs like CrossFit as well as weightlifting and powerlifting are well known for causing frequent muscle soreness.
Did you know?
HMB is one of the few supplement ingredients to get the thumbs up from the International Society of Sports Nutrition (ISSN)
You can read their recommendations here:
4.The research on HMB
The published research on HMB is varied in many ways: From the level and type of athlete used as subjects (from novice to highly trained, weightlifter to distance runners and football players) to the duration of study (weeks to several months). Much of this research is listed at the end of this article.
What usually remains the same is the dosage of HMB (3g/day), which is considered an effective supplementation dose. This is usually broken down into two to three doses a day. This is because HMB is cleared from the system relatively quickly.
Most of the research on HMB is focused on performance in athletes doing strength training/power lifting (squats, bench press, deadlifts etc.) however a select few look at endurance performance in rowers and runners. Recent research suggests that one of these doses should be taken before you train for optimal results (18).
Athletes that will benefit from HMB
Athletes wanting more from their training
Ageing athletes wanting to keep muscle
Injured athletes wanting to get back to training quicker
Weightlifters wanting to keep weight down
Team sports athletes
5.HMB is legal and completely safe to take
In 2000, research was published that took blood samples from 128 men and women of all ages using HMB. The research found that HMB was completely safe to take with no reported side effects (19). In spite of this, HMB has not been tested on athletes below the age of 18, or during pregnancy.
HMB is classified as a dietary supplement and is NOT on the World Anti Doping Agency (WADA)'s list of banned substances, meaning it is OK to take if you are an athlete who is drug tested. It is also a regulated supplement meaning that licensed HMB sellers are held to manufacturing quality requirements that will also reduce the likelihood of contamination. This being said, you should always find out what your supplement providers do to protect you as an athlete if you are drug tested.
6. Adding creatine for the strength athlete
Our bodies require Creatine to store energy in the muscles for high power explosive movements like sprinting or heavy weightlifting. We normally get Creatine from eating meat.
Supplementing the diet with creatine has been shown in many research studies to enhance strength and mass with training, thought to be through increased muscle water and providing energy for better training (20)
HMB and Creatine are two of the most researched sports supplements available on the market, having been tested in over 100 research labs. Their ability to increase muscle mass and strength with weight training are similar, yet research has shown that they work differently, meaning that using them together combines their effects. Research into the combination found that they may even double the effects of training (6).
7.Other interesting facts about HMB
HMB is difficult and expensive to make. For this reason, there are a lot of low quality or even fraudulent products on the market. Click here for a guide on how to choose better HMB.
HMB doesn't really have much taste to it so it is often mixed with juices like grape or orange. HMB is linked to calcium meaning it quickly and easily dissolves in liquid and is absorbed into the body.
Calcium-HMB, which is the form we use in our supplements, is the same form it has been tested in. Calcium HMB is completely safe to take with no reported side effects. Ever.
HMB’s effects will be reduced if you are not training hard or, as in the case of highly trained athletes, your potential for adaptation to training is smaller (think how much training a 100m sprinter puts in for a tenth of a second speed improvement). For this reason, research on elite athletes has found that HMB only results in small gains in strength and endurance.
HMB's effects are most beneficial when you are pushing your body to its limits in order to stimulate muscle adaptation.
1. Thomson et al. (2009): Controlled 9 week study on trained men. HMB increased lean mass, decreased fat mass and resulted in a substantial increase in lower body strength. Read the research
2. Nissen & Sharp (2003): A meta-analysis of all research to date on supplementation for strength and mass. Found that HMB and creatine are the only two supplements that have been shown to enhance strength and mass with resistance training. Read the research
3. Rowlans & Thomson (2009): A meta-analysis of existing research. HMB supplementation resulted in clear overall increases in strength in men starting a resistance training program, but the benefit of HMB in trained athletes was smaller. Read the research
4. Vukovich et al. (2001): Controlled 8 week study in weight training elderly men. HMB increased muscle strength and lean mass while increasing fat loss. Read the research
5. Lamboley et al. (2007): Placebo controlled study in college students. HMB supplementation increased maximal oxygen consumption by 5%. Read the research
6. Jowko et al. (2001): Controlled study in weight training males using creatine and HMB in combination. HMB and creatine supplementation results in even greater strength and lean gains than either HMB or creatine supplementation alone. Read the research
7. Baier et al. (2009): 1 year long controlled study in the elderly. HMB with two amino acids increased lean mass and protein turnover in older adults. Read the research
8. Slater et al. (2001): Controlled study in trained males. HMB enhanced strength and mass but the increases were small over the research period. Read the research
9. Vukovich & Dreifort (2001): Controlled study in trained cyclists. HMB supplementation increased cyclist endurance as measured by VO2 peak and lactic acid build-up. Read the research
10. Panton et al. (2000): Controlled study using male and female trained and untrained subjects. The study showed that regardless of gender or prior training, HMB increases strength and minimizes muscle damage when combined with a four week resistance-training program. Read the research
11. Kraemer et al. (2009): 12 week study on resistance trained men. HMB combined with two amino acids doubled the effects of training on lean mass and increased fat loss. Read the research
12. Gallagher et al. (2000): Controlled study with male weight lifters. HMB increased lean mass and peak muscle torques. It also decreased blood markers of muscle damage. Read the research
13. Knitter et al. (2000): Controlled study in male and female runners. HMB reduced muscle damage after a prolonged run as well as the perception of muscle soreness. Read the research
14. Kreider et al. (1999): Controlled study of 40 experienced, resistance trained men over just 4 weeks. HMB numerically increased lean mass and strength over the period of the study. Read the research
15. Wilson et al. (2008): A review of research on HMB. Concluded that collectively there is not only clinical data, but also mechanistic data supporting HMB's effect on increasing muscle mass and strength. Read the research
16. Nissen et al. (1996): Two controlled studies in weight training males for three and seven weeks. HMB increased strength and muscle mass while reducing muscle damage in all subjects. Read the research
17. Ransone et al. (2003): Controlled study in 35 trained collegiate football players. HMB increased muscle mass and reduced body fat however this was not statistically significant probably because the athletes only used HMB for 4 weeks so gains were small. Read the research
18. Wilson et al. (2013): The official position paper of the International Society of Sports Nutrition on HMB supplementation. HMB is one of the few supplements considered to be both safe and effective by the society. Read the research
19. Nissen at al. (2000): A series of small research studies looking at HMB safety in different age groups and genders found HMB to be safe to take and even beneficial to health. Read the research
20. Buford et al. (2007): The ISSN position stand on Creatine summarizes the research on the supplement ingredient. Read the research
21. Durkalec-Michalski & Jeszca (2016): A placebo controlled crossover study in 58 highly trained male athletes showed an increase in lean mass, reduction in fat mass and improvements in aerobic training performance. Read the research