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Jumat, 12 Februari 2016

HMB for Every, Not Just Strength Athletes? Lower Body Fat, Improved VO2, Muscle, Testosterone in 2x12 Week Study

Lean muscle for athletes? HMB could help, irrespective of exercise type - by increasing strength, lean mass and VO2. In the study at hand, all three increased and that is / was in highly trained athletes.
You've read all articles about HMB at the SuppVersity? In that case you will be aware that HMB has hitherto been perceived rather as a strength / bodybuilding than an endurance supplement. Against that background it may come as a surprise that researchers from the Poznán University of Life Sciences in Poland chose to study the effects of HMB on the aerobic capacity (Burkalec-Michalski. 2016), instead of the usual study outcome, the subjects' strength. Is that a bad thing? Not at all!

After all, there are  more sports that require optimal aerobic performance than sports that require (only) optimal strength performance. It thus makes perfect sense that Krzysztof Durkalec-Michalski and Jan Jeszka chose aerobic performance as their primary, but not only study outcome.
Learn more about the potential beneficial effects of HMB at the SuppVersity:

HMB For Fat Loss?

Hica & HMB in Yogurt

More on HMB Free Acid

Breakthrough HMB Science

HMB + Whey = Useless?!

HMB Hampers Fat Loss?
Don't worry, though! With the body composition (unfortunately only BIA data) as second outcome measure, the results the scientists derived in an experiment that involved 58 male athletes aged 22 ± 6 years, with body weight of 82.9 ± 12.3 kg and height of 181 ± 7 cm, practicing wrestling (n = 12), judo (n = 10), Brazilian jiu-jitsu (n = 14), karate (n = 6), and rowing (n = 16) are still interesting and relevant for those of you who don't care that their aerobic conditioning forces them to take the elevator.

The subjects were asked to complete dietary records every second week to ensure that they did not change their dietary habits during the two 12-week supplementation periods during which the subjects alternately consumed HMB or a placebo supplement (for 12 weeks each with 10 days wash-out inbetween).
"The experiments were conducted using a preparation of calcium salt of β-hydroxy-β- methylbutyric acid, produced by Olimp Laboratories. A single capsule contained 1250 mg Ca-HMB, which corresponds to 1000 mg β-hydroxy-β-methylbutyrate. The producer also prepared a placebo preparation containing maltodextrin. The tested group of athletes was administered 3 capsules of the assigned preparation a day, in 3 doses as follows: upon waking, immediately after training, and before sleep. On nontraining days, the participants were instructed to consume one serving with each of three separate meals throughout the day" (Burkalec-Michalski. 2016 | my emphasis).
As you will remember based on previous SuppVersity articles, the HMB dose of 3g per day (in 3x1g doses) is what previous studies have shown to trigger significant improvements in performance and body composition in even shorter times-spans (Nissen. 1996; Lamboley. 2007; Wilson. 2008; Portal. 2011; Zanchi. 2011).
Ca-HMB or free acid? There is no doubt that this is another study to put a questionmark behind the necessity of buying the expensive free acid gel of HMB. More than 90% of the previous (mostly promising) HMB studies have been conducted with calcium HMB consumed either once or, as in this case, thrice a day. In contrast to the functionality of Ca-HMB, however, the increased speed of absorption scientists have observed for the free acid form of HMB has yet to be proven to have practical relevance.
In conjunction with the previously not mentioned blood draws, the weighing and BIA measurements, as well as the ergometer tests that were performed at the beginning and end each of the 12-week study periods clearly support the scientists conclusion that...
"[t]he results indicate that supplying HMB promotes advantageous changes in body composition and stimulates an increase in aerobic capacity, while seeming not to significantly affect the levels of the analyzed blood markers" (Burkalec-Michalski. 2016).
Here, the scientists refer to the observed beneficial effects on fat-free mass (+0.2 kg HMB vs. -1.0 kg PLA, P = 0.021), with a simultaneous reduction of fat mass (-0.8 kg HMB vs. +0.8 kg PLA, P < 0.001), as well as the augmented increases in maximal oxygen uptake (VO2max: +0.102 L·min-1 HMB vs. -0.063 L·min-1 PLA, P = 0.013), time to reach ventilatory threshold (TVT: +1.0 min HMB vs. -0.4 min PLA, P < 0.0001), and the threshold load and heart rate at ventilatory threshold (WVT: +20 WHMB vs. -7 WPLA, P = 0.001 // HRVT: +8 bpm HMB vs. -1 bpm PLA, P < 0.0001).
Figure 1: HMB supplementation lead to sign. improvements in body composition (BIA | Burkalec-Michalski. 2016)
If and to which extent these effects were related to statistically significant increase in testosterone levels (P = 0.047), which, in contrast to the increase in cortisol, occurred only in the HMB group, is difficult to say (see Figure 1).
Figure 2: Changes in testosterone and cortisol during the treatment phase; * p < 0.05 (Burkalec-Michalski. 2016).
In view of the fact that the testosterone to cortisol ratio did not differ significantly in the two groups, it is yet very unlikely that the hormonal changes played a decisive role in terms of the previously discussed study outcomes.
As you can see, the study at hand confirmed that HMB is not a "strength supplement"; increases in VO2max, the ventilatory threshold and even the maximal wattage in trained athletes are an argument in favor of Ca-HMB for every, not just endurance athletes. I mean, who wouldn't want to get faster, stronger, and in better shape.
Bottom line: Even though the supplement company that produced the HMB product that was used in the study is explicitly mentioned in the methodology section of the paper, the authors report "no conflicts of interest with this work". It does therefore appear unwarranted to question the results based on potential bias. What you should question, though, is your own interpretation of the results. The use of HMB did, after all, not provide a steroid-like advantage to the athletes.

What's even more relevant than the effect sizes, though, is the fact that the benefits occurred in the absence of protein supplementation. If we assume that the differences persist and that similar effects would be observed if HMB is consumed on top of three whey protein shakes per day, though, the study at hand provides one of the most convincing arguments in favor of a supplement that is close to being unpalatable (buy caps, boys & girls ;-) | Comment!
References:
  • Durkalec-Michalski, Krzysztof, and Jan Jeszka. "The Effect Of Hmb On Aerobic Capacity And Body Composition In Trained Athletes." The Journal of Strength & Conditioning Research (2016).
  • Lamboley, Cédric RH, Donald Royer, and Isabelle J. Dionne. "Effects of beta-hydroxy-beta-methylbutyrate on aerobic-performance components and body composition in college students." International journal of sport nutrition and exercise metabolism 17.1 (2007): 56.
  • Nissen, S., et al. "Effect of leucine metabolite β-hydroxy-β-methylbutyrate on muscle metabolism during resistance-exercise training." Journal of Applied Physiology 81.5 (1996): 2095-2104.
  • Portal, Shawn, et al. "The effect of HMB supplementation on body composition, fitness, hormonal and inflammatory mediators in elite adolescent volleyball players: a prospective randomized, double-blind, placebo-controlled study." European journal of applied physiology 111.9 (2011): 2261-2269.
  • Wilson, Gabriel J., Jacob M. Wilson, and Anssi H. Manninen. "Effects of beta-hydroxy-beta-methylbutyrate (HMB) on exercise performance and body composition across varying levels of age, sex, and training experience: A review." Nutrition & metabolism 5.1 (2008): 1.
  • Zanchi, Nelo Eidy, et al. "HMB supplementation: clinical and athletic performance-related effects and mechanisms of action." Amino acids 40.4 (2011): 1015-1025.

Kamis, 29 Oktober 2015

Cardio After Weights! Doing Resistance Before Endurance Training Has More Beneficial Effects on Leptin, Cortisol, Testosterone and Body Composition in Young Men

I can almost guarantee that the results of this study are not sex-specific. Ladies, pick up the weights fater you hit the treadmill, stairmaster, elliptical or other torture instrument you like to use!
It has been a while since the last study on exercise order (cardio or weights first) has been published. Now, scientists from the University of Kurdistan have conducted another study to investigate the effects of intrasession sequencing of concurrent resistance and endurance training on the serum leptin, testosterone, cortisol responses and body composition in obese men.

And don't worry, we are not talking about useless acute-phase data that shows no correlation with either strength or muscle gains, or fat loss (West. 2012). Sheikholeslami-Vatani and colleagues conducted an eight-week study on thirty obese young male students without continuous exercise history (age: 23.2±1.4 year, BMI: 31.8±1.6 kg/m²).
You can learn more about the optimal exercise order at the SuppVersity

Before, After or In-Between?

Exercise Order and Leptin Levels

Cardio First for Anabolism?

Large Muscle Groups First?

Combine Cardio & Strength, Right

Exercise Order Reloaded
The subjects were randomly divided into three groups: concurrent resistance-endurance (CRE, n = 10) group, concurrent endurance-resistance (CER, n = 10) group and control (C, n = 10) group (no training program). The concurrent training groups (CER and CRE) trained three times a week on alternate days for 8 weeks. The training itself consisted of which consisted of ...
"running with 70—75% of maximal heart rate (HRmax) for 10 minutes which gradually increased to 80% HRmax for 21.5 minutes [plus] resistance training consisted of 3 sets of 8 repetitions at 80% of 1 repetition maximum (1RM) in 5 resistance exercises (leg extensions, lying leg curl, triceps pushdown, bench press and lateral pull down)" (Sheikholeslami-Vatani. 2015). 
In-between the endurance and resistance (or vice versa) training parts of the workouts, the subjects rested for 5 minutes. Blood sampling and skin-fold measurements to asses the body composition was conducted 48 hours before the start of the course and again 48 hours after the last training session (learn why waiting longer for the body comp test may have been better, but no study does that).
Figure 1: Relative changes in hormone levels (left) and absolute and relative changes in body fat fat free mass and body fat % (right) after 8 weeks of doing nothing (C) or doing cardio (CER) or weights (CRE) first (Sheikholeslami-Vatani. 2015).
I've plotted the most important results in Figure 1a & b. So, let's take a look: The first thing that everyone should see is that both workout regimen had relevant health and physique effects:
  • Similar gains w/ weights vs. cardio first in trained men | more.
    normalization of leptin levels (health)
  • slight increases in testosterone (health)
  • increases in cortisol (which are benign | learn why)
  • significant reductions in body fat (health + physique)
  • increases in fat free mass (health and physique)
In that, the resistance training first (CER) group came off slightly better in all tested study outcomes. Statistical significant inter-group differences, however, were observed only in comparison to the control group. In view of the fact that the body fat (total and %) improvement reached statistical significance compared to control only in the endurance first, group, yet not in the strength first group, one may still argue that the difference between cardio first (CER) and weights first (CRE) was "almost significant" ;-)
Weights or Cardio? What's the Best Visceral Fat Burner + How Often, Long and Intense Do You Have to Train | Learn more!
So, weights first is the way to go? Well, I assume I should write that doing both on separate days and thus doing having 5-6 workout days per week may have even more pronounced effects on the body composition of obese young men. In the end, though, I have no evidence to prove that doing the same amount of cardio on a separate day would actually have yielded greater improvements in body composition. Against that background and in view of the fact that three workouts per week is everything that fits into the busy schedules of the average trainee, we are left with the confirmation that (a) doing (intense) cardio and weights in one session feasible and effective when the goal are health and physique improvements and that (b) if you or your clients combine both, you better start with the weights, not the cardio part | Comment!
References:
  • Sheikholeslami-Vatani, D., et al. "The effect of concurrent training order on hormonal responses and body composition in obese men." Science & Sports (2015).
  • West, Daniel WD, and Stuart M. Phillips. "Associations of exercise-induced hormone profiles and gains in strength and hypertrophy in a large cohort after weight training." European journal of applied physiology 112.7 (2012): 2693-2702.

Rabu, 21 Oktober 2015

Low Grade Metabolic Acidosis May Eat Away Your Bones and Blow Up Your Belly Via Empowering Glucocorticoids!

The way we eat and live is not just obesogenic it is also acidogenic... or is the former just a consequence of the latter? 
I've written about the nasty effects of low grade metabolic acidosis which include calcium loss and brittle bones, nitrogen / protein loss and decreased protein synthesis, impaired growth hormone and IGF-1 production and more in a 2013 SuppVersity Science Round-Up (read it).

For you, as a SuppVersity veteran who's read this and related articles, it should thus not be surprising that scientists from the German Aerospace Center in Cologne were now able to establish a new, mechanistic link between the "long-term ingestion of habitually acidifying western diets may constitute an independent risk factor for bone degradation and cardiometabolic diseases" (Buehlmeier. 2015).

As Judith Buehlmeier and her colleagues point out, we have long been aware of the ill effects of low-grade metabolic acidosis (LGMA), as induced by high dietary acid load or sodium chloride (NaCl) intake and a lack of alkaline foods and nutrients in the average Western diet. What has hitherto not been fully elucidated is the underlying mechanisms, which is not as simple as the dissolving tooth in a glass of coke would suggest.
You can learn more about bicarbonate and pH-buffers at the SuppVersity

The Hazards of Acidosis

Build Bigger Legs W/ Bicarbonate

HIIT it Hard W/ NaCHO3

Creatine + BA = Perfect Match

Bicarb Buffers Creatine

Alkalosis Boosts Muscle Activity
In their latest study, the researchers from the German Aerospace Center in Cologne and their colleagues from the Universities of Bonn and Heidelberg do now present the first convincing evidence that the previously cited catabolic / anti-anabolic effects of chronic low-grade acidosis (LGMA) are triggered by interactions of the acid–base balance with the metabolism of glucocorticoids (GC). In said, study, the researchers "aimed to investigate GC activity/metabolism under alkaline supplementation and NaCl-induced LGMA" in eight young, healthy, normal-weight men who participated in two crossover designed interventional studies.
Figure 1: Correcting a diet-induced low grade metabolic acidosis with K-bicarbonate reduces the nitrogen loss of 750mg - 1000mg per day (per 60kg BW) in post- menopausal women in a prev. study (Frassetto. 1997)
  • In Study A, two 10-day high NaCl diet (32 g/d) periods were conducted, one supplemented with 90 mmol KHCO3/day.
     
  • In Study B, participants received a high and a low NaCl diet (31 vs. 3 g/day), each for 14 days. During low NaCl, the diet was moderately acidified by replacement of a bicarbonate-rich mineral water (consumed during high NaCl) with a non-alkalizing drinking water. 
In repeatedly collected 24-h urine samples, potentially bioactive GCs (urinary-free cortisol / free cortisone), as well as tetrahydrocortisol (THF), 5a-THF, and tetrahydrocortisone (THE), were analyzed.
Even Low Grade Acidosis Will Increase Your Diabetes Risk | learn more!
Beware! It does not take much to mess you up! A quantitative analysis of the data from the study at hand shows that even increases of dietary acid loads in the magnitude of only 30 mEq/d, which drive the renal net acid excretion into a range that is commonly seen in people on the standard Western diet (60–70 mEq/d), suffice to affect glucocorticoid activity in ways that may ruin your bone, heart and muscle health. In that, the main offenders are grains, not meats. Grains contribute an estimated 38% to the net acid load of the avg. Westerner (Sebastian. 2002).
A brief glimpse at the glucocorticoid levels in the urine of the subjects (see Figure 2) shows that with supplementation of 90 mmol KHCO3, the marker of total adrenal GC secretion dropped (p = 0.047) and potentially bioactive-free GCs were reduced (p = 0.003).
Figure 2: aily adrenal cortisol secretion as indexed by the sum of excretion rates of the 3 major urinary glucocorticoid (GC) metabolites tetrahydrocortisol, 5a-tetrahydrocortisol, and tetrahydrocortisone (THF + aTHF + THE) as well as excretions of potentially bioactive-free GCs (UFF + UFE | Buehlmeier. 2015)
This is particularly interesting if we also take into account that in Study B, the GC secretion and potentially bioactivefree GCs did not exhibit the expected fall with NaCl-reduction as net acid excretion was raised by 30 mEq/d. In conjunction study A + B do thus underline the important role of alkalizing agents like bicarbonate or potassium - irrespective of the total intake of NaCl, of which the study at hand confirms that it is part of the problem. Its ill effects, however, appear to be mediated mainly, if not exclusively, via the acidifying effects of chloride.
Bottom line: As the authors point out, their study is the first to provide convincing evidence that the ill effects of chronic low-grade metabolic acidosis are mediated via enhanced glucocorticoid activity and secretion. In that, the pro-acidic effects of NaCl, as well as the lack of alkalizing foods and nutrients in the Western diet are the main motors of dietary induced glucocorticoid elevations.

Inactivity amplifies the ill effect of glucocorticoids on muscle loss by up to 213% (Ferrando. 1999).
These elevations are - in spite of being still in the physiological range - significant enough to compromise bone quality (Bedford. 2010; Shi. 2015), cardiometabolic health & diabetes (Prodam. 2013; Qi, 2007), and protein turnover (Frassetto. 1997 | see Figure 1; Buehlmeier. 2012), and appear to be particularly unfavorable under conditions of physical inactivity (Ferrando. 1999 | see Figure on the right). Reason enough for the authors to conclude that "[a]ccordingly, higher dietary acid loads may, in the long run, constitute an independent GC-driven musculoskeletal and cardiometabolic risk factor related with western dietary habits" (Buehlmeier. 2015) | Comment!
References:
  • Bedford, Jennifer L., and Susan I. Barr. "The relationship between 24-h urinary cortisol and bone in healthy young women." International journal of behavioral medicine 17.3 (2010): 207-215.
  • Buehlmeier, Judith, et al. "Alkaline salts to counteract bone resorption and protein wasting induced by high salt intake: results of a randomized controlled trial." The Journal of Clinical Endocrinology & Metabolism 97.12 (2012): 4789-4797.
  • Ferrando, Arny A., et al. "Inactivity Amplifies the Catabolic Response of Skeletal Muscle to Cortisol 1." The Journal Of Clinical Endocrinology & Metabolism 84.10 (1999): 3515-3521.
  • Frassetto, L., R. Curtis Morris Jr, and A. Sebastian. "Potassium bicarbonate reduces urinary nitrogen excretion in postmenopausal women." The Journal of Clinical Endocrinology & Metabolism 82.1 (1997): 254-259.
  • Qi, Dake, and Brian Rodrigues. "Glucocorticoids produce whole body insulin resistance with changes in cardiac metabolism." American Journal of Physiology-Endocrinology and Metabolism 292.3 (2007): E654-E667.
  • Prodam, Flavia, et al. "High-end normal adrenocorticotropic hormone and cortisol levels are associated with specific cardiovascular risk factors in pediatric obesity: a cross-sectional study." BMC medicine 11.1 (2013): 44.
  • Sebastian, Anthony, et al. "Estimation of the net acid load of the diet of ancestral preagricultural Homo sapiens and their hominid ancestors." The American journal of clinical nutrition 76.6 (2002): 1308-1316.
  • Shi, Lijie, et al. "Higher glucocorticoid secretion in the physiological range is associated with lower bone strength at the proximal radius in healthy children: importance of protein intake adjustment." Journal of Bone and Mineral Research 30.2 (2015): 240-248.