HMB: What Is It and What Can it Do For You?

HMB

People are often looking for a way to reduce muscle soreness following intense exercise....or when it's their first time back to the gym in a few months and are dreading the dreadful delayed onset muscle soreness (DOMS).  There may be a supplement that can help with this issue. Hydroxy-beta-methylbuterate or HMB, is a metabolite of the branch-chain amino acid, leucine.  Leucine has been shown to have several positive effects when consumed in conjunction with a structured training program due to its anti-catabolic effects:

1.  Leucine may help increase lean muscle, strength and decrease body fat following a resistance training program.

2. Help decrease muscle soreness following intense exercise.

3. Help prevent declines in testosterone levels following intense training periods.

4. Help stimulate protein synthesis and slow down protein breakdown.

It was originally assumed that leucine was the key player in the afore-mentioned processes until the notion of HMB being involved came about in the late 90's.  When HMB is combined with a training program it appears to help aid with recovery.  Specifically it may help slow down muscle breakdown during/following intense exercise (i.e. heavy resistance training or 2-a-days).  Therefore if someone is beginning a new training program or upping the intensity, adding HMB to your daily supplement stack may help improve gains in muscle mass, strength and power over time.  It could also help an individual who is trying to cut weight, specifically fat, during a cutting phase by helping maintain lean muscle tissue even though their is a negative energy balance.  Your body does produce leucine each day however only about 5% of leucine is converted into HMB daily....so,

 "To put this into perspective, an individual would need to consume over 600 g of high quality protein to obtain the amount of leucine (60 grams) necessary to produce the typical 3 g daily dosage of HMB that is commonly used" 
                          -ISSN Position Stand on HMB

The following conclusions were released by the International Society of Sports Nutrition in their position stand:

1. HMB can be used to enhance recovery by attenuating exercise induced skeletal muscle damage in trained and untrained populations.

2. If consuming HMB, an athlete will benefit from consuming the supplement in close proximity to their workout. 

3. HMB appears to be most effective when consumed for 2 weeks prior to an exercise bout. 

4. Thirty-eight mg/kg of Body Mass daily of HMB (or about 3-4 g for a 200 lb individual) has been demonstrated to enhance skeletal muscle hypertrophy, strength, and power in untrained and trained populations when the appropriate exercise prescription is utilized.

5. HMB has been demonstrated to increase Lean Body Mass and functionality in elderly and sedentary populations. 

6. HMB ingestion in conjunction with a structured exercise program may result in greater

declines in fat mass (FM). 

7. HMB's mechanisms of action include an inhibition and increase of proteolysis and

protein synthesis, respectively. 

8. Chronic consumption of HMB is safe in both young and old populations.

Reference:

Wilson et al.: International Society of Sports Nutrition Position Stand: beta-hydroxy-beta-methylbutyrate (HMB). Journal of the International Society of Sports Nutrition 2013 10:6.