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Knowledge from the North
Science Updates from the CSEP

By Dr. John M Berardi, Ph.D.
First published at www.t-mag.com, Nov 10 2000.

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Blame Canada!

America has been invaded by Canada. Yep, it's true. That's what we get for that whole "world's longest unprotected border" thing. It was a subtle invasion. First they sneaked in Jim Carrey. He made us laugh so we let our guards down. Then came Shania Twain. She was a cutie so we let her in. Then came the success of Celine Dion, which only proves that Americans really do like Canadian beer and whisky. Soon, hockey began to catch on and since the rules actually allowed fighting we just had to let that one slip by, right?

Now it's too late. The Canadians have almost taken over. Soon we'll all be wearing lumberjack shirts, the cost of living will go up, the bald eagle will be replaced by the beaver and we'll be forced to listen to Loverboy and Anne Murray until we pledge allegiance to the big red maple leaf!

Think aboot it, uh, I mean, about it. Those pesky Canucks have even taken over our gyms! Have you let your training be influenced by Charles Poliquin? How about Charlie Francis? Even T-mag has featured interviews with Mariam Power, Dr. Ken Kinakin, and Mauro DiPasquale. Hey, wait just a dog-gone minute. Wasn't TC actually born in Canada? Run for your lives! The Canucks are coming, the Canucks are coming!

Okay, okay, I'm just kidding. Although I was born and raised in the good ol' US of A, I do currently live, work, and study in Canada. Although the Canucks might argue otherwise, I think this affords me the liberty to poke fun at our burly neighbors to the North, eh?

All joking aside, there's one thing about Canada that I'm really digging during my tenure here and it's not the beer. It's the science. I'm currently at the University of Western Ontario, a research powerhouse in its own right. Within a two hour radius there are several other high-powered research programs including the University of Guelph, McMaster University, and University of Toronto. If research is your game, Ontario's certainly got game.

In October, the Canadian Society For Exercise Physiology (CSEP) held its annual meeting way out west in the Canadian Rockies. Canmore, Alberta to be exact.

Oh yeah, science. You want to hear about the research, don't you? The theme of this year's meeting was "Muscles in Action." As I did in my ACSM article, I'll summarize all the interesting studies and present them here. Since all research starts with a question, that's how I'll present the info.

EXERCISE STUDIES

Is training load based on weight lifted as a percentage of max reps sufficient for exercise prescription?

The Study: Subjects performed three sets of dumbbell rows. The sets consisted of 10 reps with a weight they could initially do for 12 reps to failure. Subjects were then given two minutes rest between sets. An accelerometer measured the vertical acceleration of the dumbbells and a total load was calculated based on the Newtonian Equations of Motion. These laws suggest that load on a joint is based on both weight lifted and the acceleration of that weight. So basically the load on a joint would differ severely if the acceleration of a weight changed significantly while the weight remained the same.

The Results: A "within set" decrease in acceleration was observed. This was consistent with a rep to rep variation in speed. This variation could be indicative of variation in the neuromuscular strategy used to control motion and delay fatigue. This demonstrates that weight recommendations alone are insufficient to load assignment and that tempo is also important for exercise prescription.

Comments: As usual, science is slowly catching up with real world training advice. This study verifies the importance of not only prescribing weight as a percentage of your 1RM, but also prescribing a time under tension (TUT) to go along with that percentage of RM in order to ensure a specific and consistent load on the joint.

Since competitive cycling at very low (more aerodynamic) body positions has been shown to increase the energy needed to do the same amount of work as sitting upright, could regular training at these low positions help the athlete to be more efficient?

The Study: Nine competitive cyclists were split up into two groups, one group who trained at high trunk angles (less aerodynamic) and one group who trained at low trunk angles (more aerodynamic). Metabolic and respiratory measures were taken on each subject during 10-minute testing bouts of cycling. During these bouts, both groups cycled at high positions as well as low positions to measure the efficiency of both.

The Results: Subjects who regularly trained low were just as efficient in both the high and low riding positions. However, the subjects who trained high were less efficient in the more demanding low position.

Comments: Although this study examines a specific training tactic, it also speaks to the general concept of training specificity. If you train in a more energy demanding position, your efficiency at that, as well as other positions, will improve. In other words, athletes should probably stand up when doing overhead presses and other exercises where applicable.

Is there a predictable relationship between heart rate and resistance exercise?

The Study: Subjects performed a variety of exercises at several different loads and several different repetition ranges to determine peak heart rate responses during the lifting conditions.

The Results: Strong linear relationships were found for load, repetitions, and peak heart rate. With reps being constant (i.e., 10 reps for all sets), peak heart rate during the set went up as load was increased to maximum. As load was increased above max and reps declined, peak heart rate continued to increase. It was also found that rest periods of 3:1 or 4:1 (rest:time to complete set) were sufficient to return the heart rate to baseline levels.

Comments: The goal of this study was to determine if heart rate would be a good measure of exercise intensity and effort for resistance training. This could be important in determining if athletes are training at a desired level. I've seen many an athlete "dog it" while putting on a straining face for the benefit of their coach or trainer. You can't fool the heart rate monitor, though. In addition, this measure would also be important for the determination of when to increase your resistance training intensity. If three sets of 10 reps at a given weight isn't eliciting the necessary peak heart rate, then it's time to up the weight.

Is the medicine-ball toss a good measure of explosive power?

The Study: Twenty competitive "jump athletes" were measured for vertical jump height and backward overhead medicine ball toss.

The Results: There was a high correlation between the two tests for measures of explosive power. Since vertical jump is a standard power measure, but is biased in favor of jump athletes like volleyball and basketball players, the medicine ball toss might be a better measure of power in non-jump athletes.

Comments: The backward overhead medicine ball toss may be a better measure of overall power due to the fact that it makes use of the entire body rather than just leg power as in the vertical jump. In addition, regularly training with this type of exercise may be superior to jump training because it imparts less stress on joints of the lower body. Also, since this movement is similar to a power clean, it could be used as an alternate to that exercise in athletes who have trouble mastering the proper form.

SUPPLEMENT STUDIES

Does creatine intake downregulate muscle creatine transporters (CreaT) or change creatine phosphorylation parameters?

The Study: Subjects received either 10 grams of creatine with 73 grams of carbohydrate or placebo and 73 grams of carbohydrate during eight weeks of resistance training. Creatine transporter levels were measured before and after the training and supplementation. In addition, mitochondrial creatine kinase (the enzyme responsible for the rephosphorylation of free creatine in the muscle) levels were measured.

The Results: No differences between placebo and creatine groups were seen in creatine transporter levels. This indicates that no downregulation occurred. In addition, both groups did have an upregulation of mitochondrial creatine kinase indicating enhanced creatine rephosphorylation kinetics. No differences were seen between supplement groups for this measure. It appears that creatine supplementation had no effect on creatine phosphorylation kinetics.

Comments: Although in rats, the creatine transporter is downregulated with creatine intake, it appears that this isn't the case in humans. Good news.

Can an optimal creatine dosing regimen based on FFM (fat-free mass) be determined in order to minimize creatine loss in the urine?

The Study: Ten men were studied for seven days while consuming 20 grams of creatine per day. Urine was collected and creatine and creatinine excretion were measured. Regression equations were derived to determine optimal dosing regimens.

The Results: Based on generated equations, optimal loading entails consuming 0.28 g/kg FFM on days one and two of loading while 0.24 g/kg FFM should be consumed on days three through seven of loading.

Comments: Although this study was a preliminary attempt to measure an optimal dosing regimen, there are no blood creatine and creatinine data nor are there any muscle phosphocreatine data. Based on urine samples alone, we can't be certain that this protocol actually optimizes muscle phosphocreatine levels. (And this is the whole point of creatine supplementation.)

Can glutamine increase muscle mass and strength or decrease skeletal muscle breakdown?

The Study: Thirty-one male subjects received 0.9 grams of oral glutamine or placebo per kg FFM during six weeks of resistance training (that's up to 74 grams of glutamine per day in some subjects!) Subjects were measured before and after the six weeks for squat and bench press performance, body comp, and muscle protein breakdown.

The Results: Although all groups gained some lean mass and strength, the glutamine group didn't differ from the placebo group on any parameter measured. It appears that huge doses of glutamine don't improve strength and body comp or prevent protein breakdown.

Comments: Although it appears that glutamine supplementation takes one on the chin in this study, I'm just not sure why on earth subjects were give up to 74 grams of glutamine per day. In my opinion, that's way too much glutamine. These huge amounts of the single amino acid might have actually negatively impacted other amino acid kinetics in the body. I originally thought that with all of this oral glutamine, the subjects might have just had terrible stomach upset all the time and didn't eat enough, but diet recall data showed that their diets were fine. I'd really like to see this protocol repeated with more sane doses of glutamine.

Does North American ginseng alter immune function in exercising men?

The Study: Ten men received ginseng (1125 mg/day) or placebo for 35-day periods in crossover fashion. (That means each subject gets placebo for 35 days then gets ginseng for 35 days). Immune parameters were measured before, immediately after, and 30 minutes after exercise.

The Results: Ginseng improved immune function during recovery from exercise as evidenced by reduced white blood cell and neutrophil counts and increased interleukin-2 production in response to an immune challenge. Ginseng did not alter neutrophil oxidative burst or lymphocyte proliferation.

Comments: The post exercise recovery period is characterized by a weakened response to immune challenge. With the results of this study, it appears that ginseng might help to normalize the immune system after exercise. It also appears that ginseng can prevent exercise induced neutrophil alterations.

Can vitamin E supplementation prevent post-exercise oxidative muscle damage, muscle soreness, or inflammatory response?

The Study: Healthy males were supplemented with either placebo or 1200IU of vitamin E per day for 30 days. At the end of the supplementation period, subjects performed one bout of exercise consisting of 24 sets of 10 eccentric knee extensions. Subjects were measured for strength, muscle damage, muscle soreness, and inflammation immediately after the bout as well as two, three, and seven days following the bout.

The Results: Vitamin E supplementation, although it did increase plasma vitamin E concentrations, had no impact on any of the study parameters mentioned when compared with placebo.

Comments: Although oxidative damage is linked with muscle damage and soreness, researchers are unsure as to whether there's a cause and effect relationship or whether they're just related through other cellular mechanisms. This study suggests that although vitamin E may be an effective cellular antioxidant, its antioxidant effects have no impact on muscle soreness and damage.

What impact does hydroxyproply-beta cyclodextrin complexed 4-androstene3,17diol have on sex hormones in the blood?

The Study: Four men received either placebo, 15 mg of complexed diol, 25 mg of complexed diol, and 50 mg of complexed diol to be taken sublingually on separate occasions. Sex steroids including Testosterone, DHT, estradiol, DHEA, and androstenedione were measured for up to three hours after the dose of diol to determine what impact it would have on blood hormones.

The Results: Significant Testosterone increases were seen (up to 159% increase) with these small doses of diol while no other sex steroids were increased. Although 25 mg promoted greater increases than 15 mg, there was no difference between 25 mg and 50 mg. Testosterone concentrations had returned to baseline by about 120 minutes for the 15 mg dose but didn't return to baseline by three hours in the larger dose groups.

Comments: Based on the findings in this study it appears that cyclodextrin complexation can increase the bioavailability of prohormones. The diol doses in this study are one-tenth the doses seen administered by oral delivery yet the T increases are double or more than that of oral administration. It appears that this delivery system is effective at delivering a large amount of the administered dose to the blood stream while minimizing conversion to other sex steroids like the estrogens. Trouble is, you'd have to take a dose every 3 hours, and this is somewhat of a pain in the butt. Also, it appears that 25 mg of complexed diol is the upper limit on Testosterone elevations since the 25 and 50 mg doses yielded almost identical results.

Does elk antler velvet impact performance or the endocrine system?

The Study: Forty-five rowers and strength trainers participated in this 10 week study which examined supplementation with either placebo or 560 mg of elk velvet antler which, believe it or not, is sold as a dietary supplement. Subjects performed three days of resistance training and three days of endurance training per week for the study duration. Subjects were also tested before and after the supplementation period for strength, 2000 meter rowing time, VO2, and body composition. In addition, hormonal parameters were measured (total T, free T, GH, cortisol, insulin, etc.)

The Results: Although both groups improved, there were no differences between groups on any of the study parameters measured. Therefore, it appears that elk velvet antler had no impact on body comp, hormones, or performance.

Comments: Elk velvet what? Next study please…

HORMONE AND ENERGY EXPENDITURE STUDIES

What impact does a low calorie diet and lots of exercise have on thyroid function in athletic females? Note: Remember that total daily caloric needs = basal metabolic rate + daily energy expenditure.

The Study: Twenty-nine fit, lean babes (less than 20% fat) were divided into five groups for this four-day study. All the babes exercised daily and expended about 30 calories/kg FFM. Since the subjects had an average of 47 kg of FFM, this means they expended about 1400 calories every day during exercise and to compensate for the exercise, they were fed 1400 calories as a baseline diet.

At this point, the women still required enough calories to satisfy their basal metabolic needs. This is where the five different groups come in. The women were given five different diets of about 5.5, 11.4, 18.1, 25, and 37.4 calories per kg of fat-free mass in order to fall short of, meet, or exceed basal metabolic needs. What this means is that group one got about 270 calories above exercise needs, group two got 560 calories above, group three got 850 calories above, group four got 1175 above, and group five got 1758 above exercise needs. At the end of four days of this confusing protocol, levels of T3 and reverse T3 were measured.

The Results: T3 levels declined in all groups while reverse T3 increased in all groups. However, there was a sharp drop in T3 and increase in reverse T3 in groups below the 18.1 calories/kg FFM. Subjects in these lower calorie groups experienced drops in T3 of greater than 20%.

Comments: This study confirms that people who diet and train are susceptible to hormonal fluctuations including reductions in T3 and Testosterone. The interesting thing about this study is that it only took four days of moderate to low calorie intake coupled with high-calorie expenditure to crush T3 levels!

Since T3 is the most powerful thyroid hormone, while reverse T3 is the inactive form of T3, this shift can cause some nasty physiological changes. In this study, the purpose was to examine the potential impact of hormone changes on menstrual irregularities. On a more global scale, these shifts can cause some serious physique consequences like loss of muscle mass and increases in fat mass for both men and women.

Is there an interaction between energy balance and exercise and their impact on circulating hormones?

The Study: Fifty-two men were studied. Sixteen were highly aerobically trained and their workouts consisted of 11+ hours of exercise per week. Twenty were moderately aerobically trained and their workouts consisted of 5 to 10 hours of exercise per week. The last group of sixteen just sat around watching Survivor reruns. Groups were compared for resting energy expenditure, exercise energy expenditure, energy intake and hormone concentrations.

The Results: Resting energy expenditure was similar in all groups, while exercise energy expenditure was different (highly trained > moderately trained > sedentary). Also, energy intake was greater in the high and moderately trained groups than in the sedentary groups. As far as hormones, T3 was lower in the exercised groups than in the sedentary group by about 8 to 15%. Free T was also moderately lower in the highly trained group by about 28%, but this didn't reach statistical significance.

Comments: In accordance with the last study, we can see that high levels of activity can decrease the levels of important anabolic and lipolytic hormones in the body like Testosterone and T3. It's understandable that in endurance athletes, anabolism would be a liability since lots of muscle might be hard to carry along on a marathon. But since these hormones have an impact on well being and daily function, strategies to keep these levels from crashing too low might need to be employed by those athletes.

SYMPOSIUM SESSIONS

Physiological Functions of CLA by Dr. James Ntambi

CLA (conjugated linoleic acid) has been shown to inhibit carcinogenesis (cancer) and artherosclerosis, enhance immune function, protect against catabolism, stimulate the growth of young rats, and change body composition.

In this presentation, Dr. Ntambi shared with the conference some recent data from his and other labs showing the impact of CLA on the body composition of test animals. Dr. Ntambi stated that in several studies, pigs and mice fed higher dietary levels of CLA were shown to have increases in body water and body protein while also demonstrating decreases in body fat. In the rodent study, 0.4% of the rodent's diet consisted of CLA. This dietary intervention resulted in an 11% reduction of body fat. Dr. Ntambi stated that CLA could act to decrease fat mass via a number of cellular mechanisms including:

• Decreasing the differentiation of preadipocytes into full blown fat cells
• Decreasing lipoprotein lipase activity and steroyl CoA desaturase activity (which both can lead to lipogenesis)
• Increasing lipolysis by increasing beta-oxidation (fat burning)
• Increasing carnitine palmatoyl transferase in muscle (acts to shuttle fats into the mitochondrion of the cell for fat burning)
• Decrease catabolism by inhibiting the cyclooxygenase enzymes that convert arachadonic acid into catabolic prostaglandins (basically what aspirin does)

Dr. Ntambi also pointed out that CLA has several isomers, two of which are most active and may each have individualized mechanisms of action. He also stated that although fats have been frowned upon over the last decade or two, new research on fats like CLA is leading to a better understanding of fats in the body. He states that this is imperative to helping create a distinction between good fats and bad fats.

Role of Creatine Supplementation in Muscle Growth and Exercise Performance by Dr. Peter Lemon

Dr. Lemon shared some new as well as some unpublished research on creatine supplementation. We all know that creatine is ergogenic but recent data addresses other practical aspects of creatine supplementation.

• Creatine supplementation may not always be necessary for creatine loading or maintenance. Diets high in meat may provide enough creatine over time to effectively load the muscle. Just don't expect loading to take place in five days.
• Subjects who do want to speed up the process and who load with creatine for five days may be able to maintain a loaded state from a high intake of meat alone.
• Subjects who load on creatine for five days may maintain performance benefits and body mass increases for up to five weeks after supplementation. Again, those subjects who continue to eat diets high in creatine-rich meats will probably stay loaded for longer periods of time
• The increases in body mass seen with creatine supplementation may be due to a decrease of extracellular fluid and an increase in intracellular fluid.
• The mass gains seen with creatine supplementation don't impede performance in weight bearing power activity. In stair sprinting, although all subjects on creatine gained weight, they still saw significant performance increases verses placebo. This was true even with the extra weight they had to haul up those stairs.
• Athletes who supplemented 12 weeks of training with just creatine, protein, or both saw larger increases in sets consisting of 80% of 1RM performance with the combination (300%) than with creatine alone (228%) or protein alone (163%).

Lemon pointed out that because high-protein intake (meat and fish) can load a muscle with creatine, part of the ergogenic and anabolic effects of a diet high in meat and fish protein could be related to creatine loading. In addition, Lemon stated that the future of creatine research may be in the use of creatine in individuals with muscle wasting and disease.

Andro Update 2000 by Dr. Tim Ziegenfuss

After a discussion of the five main androgen metabolizing enzymes (delta5 3beta HSD, 17betaHSD, 5alpha reductase, 3alpha HSD, and aromatase) as well as the major and minor biochemical pathways that are necessary for the production of Testosterone and other androgens and estrogens, Dr. Ziegenfuss gave a comprehensive literature review of all of the papers and abstracts that have been presented on andro in the last few years.

Dr. Z also covered the differences between the prohormone isomers (the 4 and 5 androstene 3,17, diols and diones as well as the 19- nor prohormones) and discussed why there seems to be vastly different responses to prohormone administration in different individuals. He attributed this in part to the fact that individuals often have different ratios of the aforementioned metabolizing enzymes. These differences may account for the wide variability in responses seen with andro supplementation. Basically some guys will easily make T from dione while others will become estrogen factories with dione administration. It's all based on their own levels of certain metabolic enzymes.

Finally, Dr. Z finished by discussing several of the available delivery forms of andro including oral, buccal, and sublingual delivery (sorry, Androsol is too new to have been included). Based on available data, sublingual delivery of cyclodextrin complexed diol seems to be the most bioavailable delivery form as well as the most effective Testosterone elevating prohormone in those methods studied. (We believe this will change, of course, once they begin to study Androsol and Nandrosol and their topical delivery systems.)

Protein Supplements and Recovery after Exercise by Dr. Don Layman

In arguably the most interesting and novel presentation of the conference, Dr. Layman presented fascinating information on the restoration of muscle glycogen and protein synthesis after exercise. He pointed out that although much is known about glycogen restoration, very little is known about the restoration of protein synthesis. Layman argues that muscle mass-regulation is driven primarily by protein synthesis and that synthesis should be the target of nutritional strategies designed at recovery. Here's a synopsis of his data:

• During two hours of intense endurance exercise with only water provided, muscle protein synthesis was depressed by 30% and remained low for up to eight hours. In addition, neither pre-exercise meals nor nutrient intake during exercise are able to prevent this catabolic effect.
• Post-workout protein intake does assist in recovery of protein synthesis and the sooner the protein is ingested, the faster the recovery. The provision of BCAAs (leucine, valine, isoleucine) at this time seems to be especially important.
• Traditionally, although insulin has been thought to be a major player in post-workout recovery of protein synthesis, high levels of carb intake and high insulin responses did not promote the recovery of protein synthesis.
• Interestingly, leucine alone promoted full recovery of protein synthesis by inducing a portion of the insulin signaling pathway that regulates short-term changes in muscle-protein synthesis. Leucine appears to be the rate-limiting amino acid in this pathway and therefore insulin alone can't upregulate protein synthesis without the extra leucine. Accordingly, leucine plus carbohydrate intake promoted greater recovery than leucine alone.
• It also appears that a specific ratio of BCAAs may be more important to recovery than simply a large intake.

Dr. Layman concluded that the BCAAs, although well studied and disappointing for their role in energy provision, may be very important for post-workout recovery of protein synthesis. In addition, he stated that targeting insulin in the absence of adequate provision of BCAAs has little impact on protein synthesis.

Whew! It sure was tough attending all those seminars given the beautiful setting of Canmore. I'm convinced that God himself vacations there. Yeah, it's a tough job, but somebody's got to do it.