HMB: Overrated, Overpriced, or
Overlooked Part 3
By: Derek Charlebois B.S. CPT
In part I of this series on HMB, we examined the proposed mechanism
by which HMB exerts its effects. Part II examined three studies
that examined HMB on three diverse populations. At this point,
it appeared as if everyone agreed that HMB was beneficial. But
this is not the case according to some researchers.
The Studies That Concluded HMB to be Ineffective
Kreider RB, Ferreira M, Wilson M, Almada AL. Effects of Calcium
b-Hydroxy-b-methylbutyrate (HMB) Supplementation During Resistance-Training
on Markers of Catabolism, Body Composition and Strength. Int J
Sports Med 1999; 20: 503–509[1]
This study by Kreider et al. concluded that supplementing with
HMB (3 or 6 g/day) does not effect changes in body composition
or strength and does not increase markers or catabolism. This conclusion
is the same as Kreider’s conclusions in his two previous studies
on HMB [2,3]. Let’s examine the methodology of Kreider’s third
study.
Subjects
This study consisted of 40 males with at least
one year of resistance training experience. The average training
experience of the subjects was 5.5 years. The subjects’ average
weight was 82.4 kg.
Experiment Design
All subjects were to continue their current training
program and diet. They were to record their workouts (weights used,
repetitions completed, etc.) on workout logs and nutritional intake
on diet logs. Since all subjects were doing different workouts
and consuming different diets, there was no training or dietary
control.
|
Group |
Start |
End |
Caloric Intake |
Control |
36.4 |
42.4 |
(kcal/kg/day) |
HMB (3 g) |
34.1 |
37.6 |
|
HMB (6 g) |
35.8 |
38.7 |
If the average subject weighed 82.4 kg, this means the Control
group consumed 2999.36 kcals/day, the 3 g HMB group consumed 2809.84
kcal/day, and the 6 g HMB group consumed 2949.92 kcal/day at the
first nutritional data entry.
The final nutritional input showed that the Control group consumed
3493.76 kcals/day, the 3 g HMB group consumed 3098.24 kcal/day,
and the 6 g HMB group consumed 3188.88 kcal/day. We see that the
Control group was consuming 395.52 kcals/day more than the 3 g
HMB group and 304.88 kcal/day more than the 6 g HMB group. Clearly
this caloric difference would impact the results.
Results
Body Composition
|
Group |
Start |
End |
Change |
Body Mass (kg) |
Control |
74.6 |
75.1 |
+0.5 |
|
HMB (3 g) |
76.3 |
77.3 |
+1.0 |
|
HMB (6 g) |
78.6 |
80.0 |
+1.4 |
Fat/Bone Free Mass |
Control |
59.9 |
60.2 |
+0.3 |
(kg) |
HMB (3 g) |
61.3 |
62.0 |
+0.7 |
|
HMB (6 g) |
64.1 |
65.1 |
+1.0 |
Fat Mass (kg) |
Control |
12.3 |
12.4 |
+0.1 |
|
HMB (3 g) |
12.5 |
12.8 |
+0.3 |
|
HMB (6 g) |
11.9 |
12.3 |
+0.4 |
Though the increases are small, we see that despite the caloric
difference between the groups (the Control group consuming more
calories) the 6 g HMB group gained three times as much lean mass
as the Control group. This pattern and gains are similar to the
results in one of the studies done by Nissen [4].
Strength
|
Group |
Start |
End |
Change |
Bench Press (kg) |
Control |
113.5 |
115.3 |
+1.8 |
|
HMB (3 g) |
116.5 |
117.7 |
+1.2 |
|
HMB (6 g) |
115.0 |
118.2 |
+3.2 |
Leg Press (kg) |
Control |
247.3 |
249.5 |
+2.2 |
|
HMB (3 g) |
255.2 |
263.7 |
+8.5 |
|
HMB (6 g) |
249.7 |
256.5 |
+5.8 |
Again, despite the small increases, the HMB groups’ strength increased
more than the Control group’s.
Even though the Control group consumed more total calories per
day, the HMB groups made better progress. Though the difference
is not statistically significant, it still exists. One flaw I see
in this study is that there was no dietary control. Therefore,
it is difficult to isolate other variables to further identify
either positive or negative contributions from HMB . Since the
HMB groups’ caloric intake was hundreds of calories lower than
the control group, I think this demonstrates how effective HMB
can be. I would like to know what the results would have yielded
if the HMB groups consumed the same number of calories?
Another flaw in the study is there was no training control. We
do not know if the subjects were training to failure, what % of
their 1-RM they were using, whether or not they were increasing
the weights they used when possible, etc. Training provides the
stimulus for growth. If the subjects were not inflicting a stimulus
strong enough to cause growth, they will not grow or get stronger.
The study concluded that HMB does not affect lean mass or strength,
but the results show it does. However, the lack of control in the
study makes the results questionable. This findings show why it
is important to read entire study articles and not just the abstracts.
So How Should You Use HMB?
In part II of this series, we examined a study
by Nissen et al [4] The subjects using HMB experienced much better
results than the control group, but all three groups increased
their lean mass. The increases in lean mass seen during this three-week
study were greater than the lean mass gains seen in Kreider’s study.
This could be due to the fact that the subjects in Nissen’s study
were untrained and the subjects in Kreider’s study were trained,
or it could be due to the strict training protocol in the Nissen
study.
In the Nissen study, all subjects started out by lifting at 90%
of the one repetition maximum (1-RM), which should have allowed
them to get a complete three to five repetitions. When a subject
became stronger, the weight used was increased so he would stay
within a range of three to five repetitions. Each training session
was monitored by a supervisor who decided when they subjects should
increase the weights they used. This is different from the Kreider
study in which the subjects just continued to follow their current
training routine. Why would this make a difference?
The body is like a machine that wants to maintain a state of homeostasis
(a relatively steady environment). A common example of this is
the body’s desire to maintain internal temperature. When we get
hot, we sweat. When we get cold, we shiver. The body does what
it needs to in order to adapt to the current stimuli being applied.
This principle holds true for resistance training.
Resistance lifting can be viewed as a stress being placed upon
the body. When this stress is greater than what the body is accustomed
to, it tries to adapt by strengthening itself. Resistance training
causes damage to muscle cells and connective tissue. The body then
repairs this damage and becomes stronger in order to prevent further
damage [5]. If these strengthening adaptations did not occur, we
would never have to increase the weight we are lifting in order
to grow.
Types of Training
There are two specific times
when a muscle is really stressed to adapt: after time off or strategic
reconditioning and when you increase the weight you lift. If you
have ever taken a week off from exercising, you know that during
the week you return you experience a large degree of delayed onset
muscle soreness (DOMS). Why? Because this stress is now something
your body is unaccustomed to. After about two weeks, the amount
of DOMS you experience will have most likely decreased.
When you increase the amount of weight you lift, you are applying
an unaccustomed stress to your body. It would be great if you could
continuously increase the weight you lift every workout,
but that is not possible. That is why people use periodization
in their training programs. Periodization is organizing training
sessions into workable units. A periodized program is broken up
into:
- Training Session- A single workout
- Micro Cycle- Made up of training sessions during a certain
span. The most common are 5 to 10 days.
- Mesocycle- A 1 to 4-month period made up of different micro
cycles.
Each training session, micro cycle, and meso cycle should all
have a specific purpose. It could be to cause hypertrophy (myofibrillar
or sarcoplasmic), increase capillary density, maximal strength,
muscular endurance, etc.
Periodization based programs* allow you to continually apply an
unaccustomed stress to your body by using different strategies.
This is accomplished by methodically varying your training by changing
the rep range you use, the number of sets you complete, the % of
your 1-RM you use, changing exercises, etc.
*Popular examples of programs that use periodization are Hypertrophy
Specific Training (HST) and West Side Barbell’s Cybernetic Periodization.
Why Some People Don’t See Results With HMB
What happens when you follow the same training program for a long
period of time? Your body adapts to it and you eventually reach
a plateau. Often times, people will add HMB to their program because
their gains have slowed. The problem is they do not change their
training. Therefore, HMB will not be as beneficial because their
body is not trying to adapt to an unaccustomed stress. They are
most likely not lacking the substrates needed to proper repair
cellular damage. It would be like adding water into an already
full pitcher; the excess water would just spill over the sides
and be wasted. If you are not causing damage to muscle cells, HMB
will not be effective for you (though it will have effects on protein
degradation).
With the above in mind, it would make sense that using HMB during
periods of unaccustomed training (after time off or with periodization)
would improve recovery. The body is trying to adapt to this new
stress and damage. Supplementing with HMB would provide the necessary
substrate needed to restore muscle cell membrane integrity.
Another reason why some people do not see impressive results is
they are using HMB while bulking, which means they are in a caloric
surplus. HMB exerts one of its main effects by decreasing protein
breakdown. While protein breakdown is definitely a concern while
you are hypercaloric, one will be eating sufficient calories to
negate the protein breakdown. I feel HMB is much more useful when
one is hypocaloric and trying to lose fat while maintaining muscle.
Dosage and Timing
Now that we understand how HMB
works, the studies that support it, and when it should be used,
we need to know how to use it. Most research has shown positive
results when using 3 g HMB per day. I personally feel this should
be the minimum amount used.
About half of the supplemented HMB is the studies by Nissen was
loss in the urine [6]. This is due to its short half-life. The
half-life of HMB was measured as 1 hour in rats, 2 hours in pigs,
and 3 hours in sheep, with human HMB metabolism found to be the
same as pigs’ [7] with a half-life of 2-3 hours [8]. This means
your HMB doses should be spread out evenly. I suggest taking a
serving before and after training because of the increased blood
flow to the contracting muscles. First thing in the morning and
before bed would also be good times.
Example for someone who works out in the morning taking 3 grams
a day:
- 6 AM (Pre-workout)- 500 mg
- 7 AM (Post workout)- 500 mg
- 11 AM- 500 mg
- 3 PM- 500 mg
- 7 PM- 500 mg
- 10 PM (Bedtime)- 500 mg
If you decided to take more than 3 grams per day, you could spread
the doses out more or increase the amount you take at certain times
(such pre/post workout and before bed).
Final Conclusion
From the research I’ve done and
my experiences with HMB, I feel it is a great supplement. It can
be especially useful for natural athletes looking to decrease protein
degradation while dieting or are looking for a decrease in recover
time from workouts while bulking. It is important to remember though
that if you are not creating an environment for growth with your
training 1) you will not progress and 2) HMB will not be as effective.
Anyone dieting would also benefit from HMB due to the reduced substrates
for protein synthesis and repair from their decreased caloric intake.
Since HMB’s price tag has become more reasonable, maybe you should
give it a second look. I recently added it back into my supplement
arsenal, and so far I am very pleased.
References
- Kreider RB, Ferreira M, Wilson M, Almada AL. Effects of Calcium
b-Hydroxy-b-methylbutyrate (HMB) Supplementation During Resistance-Training
on Markers of Catabolism, Body Composition and Strength. Int
J Sports Med 1999; 20: 503–509
- Almada A, Kreider R, Ferreira M, Wilson M. Effects of calcium
b-HMB supplementation with or without creatine during training
on strength and sprint capacity. FASEB J 1997; 11: A374
- Kreider R, Ferreira M, Wilson M, Almada A. Effects of calcium
b-HMB supplementation with or without creatine during training
on body composition alterations. FASEB J 1997; 11: A374
- Nissen, S. et al. Effect of Leucine Metabolite b-hydroxy-b-methlbutyrate
on muscle metabolism during resistance-exercise training. Journal
of Applied Physiology. 81(5):2095-104, 1996 Nov.
- Katch, Frank. Katch, Victor, McArdle, William (2001). Exercise
Physiology: Energy, Nutrition, and Human Performance (5th Ed.).
Maryland: Lippincott William and Wilkins.
- Nissen, S. et al. Effect of Leucine Metabolite b-hydroxy-b-methlbutyrate
on muscle metabolism during resistance-exercise training. Journal
of Applied Physiology. 81(5):2095-104, 1996 Nov.
- Nissen, Steven and Naji, Abumrad. Nutritional Role of the Leucine
Metabolite b-hydroxy-b-methlbutyrate (HMB). J. Nutr. Biochem.
8:300-311, 1997.
- Vukovich, M. D., G. Slater, M.B. Macchi, M.J. Turner, K. Fallon,
T. Boston and J. Rathmacher. b-hydroxy-b-methlbutyrate (HMB)
kinetics and the influence of glucose ingestion in humans. J.
Nutr. Biocehm. 12:631-639, 2001.
