Benefits of Calcium HMB for Endurance Athletes

Before we get into the benefits of Calcium HMB for endurance, you probably want to know what exactly it is.

What is HMB?

Beta-hydroxy-beta-methylbutyrate (HMB) is a naturally occurring chemical that can be found in foods such as grapefruit.  Humans naturally produce HMB from the amino acid leucine.  This process is long and complicated, so I will skip those details.  Let me just tell you that to produce the recommended supplementation dose of HMB, a person would need to consume over 600g of high-quality protein (Wilson et al., 2013).

Obviously, that is just a tad impractical.  Therefore, HMB is typically taken via a dietary supplement.  Currently, two forms of HMB have been used in supplementation: Calcium HMB and a free acid form (HMB-FA).  However, research with HMB-FA is relatively new, and there is not enough data to say if it is as effective as Calcium HMB for endurance.  Read on to learn about the benefits of HMB supplements, especially for endurance athletes.

Benefits of Calcium HMB for Endurance Athletes:

As always, here is a quick rundown of the scientifically studied effects of calcium HMB supplementation.

1. Improves body composition/lean mass (Wilson et al., 2013)                                        
2. Preserves muscle during prolonged exercise (Park et al., 2013)                                 
3. Preserves muscle when calorically deficient (Park et al., 2013)                                  
4. Improves recovery (Wilson et al., 2013)                                                                      
5. Decreases soreness when taken before exercise (Wilson et al., 2008)                      
6. Improves fat oxidation (Wilson et al., 2008)                                                                
7. Improves aerobic performance (Durkalec-Michalski & Jeszka, 2016)
8. Stimulates protein synthesis (Wilson et al., 2013)                                                     
9. Improves mitochondrial biogenesis (He et al., 2016)                                                 

For all the research nerds out there, let’s talk about what the science says about calcium HMB for endurance athletes.

Wilson et al. (2013) stated in the International Society of Sports Nutrition’s position stand on HMB that it:

1. Improves recovery by reducing skeletal muscle damage caused by exercise.
2. Enhances skeletal muscle growth, strength, and power when the appropriate exercises are used.
3. Increases lean body mass.
4. May result in greater decreases in fat mass when used in conjunction with a structured exercise regimen.
5. Inhibits proteolysis (the breakdown of proteins into amino acids) and increases protein synthesis (the process in which cells make proteins)

Park et al. (2013) found that HMB supplementation preserved muscle during two scenarios.  The first scenario showed that HMB supplementation preserved muscle during prolonged bouts of endurance exercise.  Second, the results showed that HMB supplementation preserved muscles when the subject was in a calorie deficit.

However, researchers pointed out that the ergogenic effects of HMB increase when the potential for muscle damage during exercise is high.  It is also inferred that the decrease in muscle soreness after working out is due to the protective effects HMB supplementation has on muscles during exercise.

Body Composition, Lean Muscle Mass and Aerobic Capacity

Durkalec-Michalski and Jeszka (2016) investigated whether HMB supplementation affected body composition and aerobic capacity.  This study showed significant increases in fat-free muscle mass, maximal oxygen uptake, and time to reach the ventilatory threshold.  Researchers also discovered a reduction in fat mass.

According to Wilson et al. (2008), several studies have produced results that support the conclusion that HMB decreases body fat, blood cholesterol, and muscle proteolysis.  Additionally, researchers posit that the increased protein synthesis and reduced protein degradation lead to improved body composition and lean muscle mass (Wilson et al., 2008).

Mitochondrial Biogenesis

What a mouthful!  If you can think back to your school days, you probably remember learning that the mitochondria are the cell’s powerhouse.  This means that they are responsible for energy production within the cell and are the main producers of ATP within cells and tissues.  Evidence shows that mitochondria may function as a vital regulator of skeletal muscle fiber types and overall health (He et al., 2016).

Furthermore, maintaining skeletal muscle mitochondrial content and function is crucial for sustaining health.  All this information becomes more relevant to this blog when you factor in that HMB has been shown to enhance the efficiency of mitochondrial biogenesis in skeletal muscle (He et al., 2016).

These benefits are great for ultra-runners and any other athlete that exercises for extended durations.  Does this not sound like the perfect supplement for these types of athletes?