by Christopher R. Mohr, RD
As a researcher who spends many hours sitting behind a lab bench and scouring the literature to learn about the most cutting edge scientific findings, it's exciting to see what else is going on in labs around the world and rub elbows with other scientists at various conferences. It would be more exciting to run elbows and other body parts with Playboy bunnies over at Hef's place, but I'll take what I can get.
These conferences are often in cities where nerdy scientists can finally take off their safety goggles, put down their pocket protectors, and see the light of day as a true tourist would. This year's annual American College of Sports Medicine meeting in St. Louis was a bit different. Unfortunately, the city wasn't too conducive to letting down your lab coat and enjoying the night life. At any rate, T-mag readers probably don't want to waste their time reading about me gallivanting around and are instead interested in the newest research findings pertaining to physique enhancement and health. So, here we go.
(Yeah, like we needed to be convinced)
Scientists from Eastern Washington University designed a research protocol to assess the effects of massage on metabolism. They measured VO2 (ml/kg/min) and RER (respiratory exchange ratio) in females continuously during the resting and recovery periods and at various pre-set periods during a one hour, full-body massage. Seems that the massage significantly increased metabolism from the resting level and this increase was maintained for a minimum of 15 minutes post-massage (5). Although this study was conducted on females, I can guarantee these results are applicable to males as well. Of course, you'll still need to train and eat right, but hey, why not get a massage (or give one) just to help things along. I can see T-mag readers now using that as a line in the gym: "Excuse me, miss, but if you'll allow me to feel you up for an hour you'll experience a nice metabolic boost. It'll also improve blood flow to certain parts of my body."
(Again)
Another group presented their research on the effects of static magnets on upper body aerobic performance. Conclusion: The magnets didn't work for any of the outcome parameters measured (or probably any others either), like oxygen consumption, blood flow, and perceptions of exertion. Surprising, huh? Funny how every "magical" piece of equipment or infomercial gimmick that's guaranteed to change your physique and/or health doesn't hold true to its promise. Wanna' know what does hold true? Hard work and dedication! (4)
Obviously, we're all interested in packing on slabs of muscle and losing body fat as quickly as humanly possible; however, let's not forget about the most important muscle in the body, the 'ol heart. Give it hell and the last thing you'll be worrying about is the size of your biceps. C-reactive protein is a circulating inflammatory marker that's recently been identified as an independent risk factor for first and recurrent coronary events (1). With this in mind, many researchers are determined to learn about this newest "bad guy" in battling CVD. Dr. Rawson and colleagues presented a study that assessed both body mass index (BMI) and high sensitivity C-reactive protein (hs-CRP) in 109 subjects. Not surprisingly, hs-CRP was significantly greater in obese and overweight subjects and it was determined that BMI (body-mass index), but not recent or previous year physical activity, predicts hs-CRP levels (2). In another study, the researchers at the Cooper Institute in Texas found that higher levels of fitness are associated with lower levels of CRP, independent of both age and BMI (3). The moral of the story is eat well, exercise, and keep the size of that gut down to prevent you from having an elevated BMI. (Keep in mind BMI is calculated without lean mass in the equation so some people, athletes and bodybuilders in particular, may be classified as obese, but are in reality far from it.) It's definitely a wise idea to ask your doc to measure your levels of CRP the next time you go in for a check-up, regardless of coronary history in your family. There seems to be a lot more to reducing levels of this pesky protein than just being physically active and eating well, so stay tuned.
Researchers from James Madison University compared a cardioresistance (CR) program (combined aerobic and anaerobic training) to resistance and aerobic only training programs. Muscular strength and cardiovascular endurance were used to assess the differences among the groups. After the 12-week protocol, the CR group had significant increases in muscular strength, as assessed via the chest and leg presses. There were no significant changes in VO2 max (which was used to assess cardiovascular endurance) among the subjects. The resistance trained subjects also increased their chest and leg presses significantly, but not their VO2 max. Finally, the aerobically trained subjects also saw small, but significant increases in all outcome parameters: chest press, leg press, and VO2 max. From this study, it seems one can derive similar benefits from a cardioresistance type program compared to a structured aerobic and/or resistance training protocol (6). Keep in mind that this type of program may be beneficial for maintaining what you've already achieved, but isn't the type of program you're looking for if you plan to bust out of your skin like the Incredible Hulk. It probably won't make you turn green either, but that's what discount protein powders are for.
Scientists from the University of Florida presented their findings from a study set up to determine the difference of onset muscle pain between genders. In their study with 67 participants, they induced delayed onset muscle soreness (DOMS) using eccentric (negative) resistance exercises for the biceps and measured pain 48 hours post-exercise. They learned that females reported lower pain intensity than males, but no significant differences in pressure threshold (which was assessed using a piece of equipment called a dolorimeter) (7). Summary: Chicks are tough.
In arguably the most well-presented study of the week, a fine young researcher named Chris Mohr, both handsome and hung like a horse, presented his findings on the effects of zinc supplementation on plasma zinc status and resting metabolic rate in physically active individuals. (Okay, okay, if you didn't catch the byline above, I'm Chris Mohr, but I still think it was a good study.) I found that supplementing with zinc does increase plasma zinc status (ground breaking, huh?) in both deficient and non-deficient physically active males and females. However, this significant increase in plasma zinc status didn't correlate to any significant effects on resting metabolic rate or lean body mass gains. After measuring baseline zinc status in dozens of college age individuals (all were physically active and some are collegiate varsity athletes), I found three deficient individuals (8). Basically, eat a well-balanced diet and zinc deficiency won't be as common as some want you to believe.
Thermogenics were next in line and Dr. Arciero presented the results of his group's study comparing green tea, caffeine, and ephedrine combinations on resting energy expenditure, fat oxidation, heart rate and blood pressure. They compared the effectiveness of 200mg caffeine, 270mg of catechin polyphenols from green tea extract, caffeine-green tea (200mg and 270mg, respectively), and caffeine-ephedrine (40mg and 12mg, respectively). In this small study with ten subjects, the researchers found that the caffeine-only group had a small, but significant increase in thermogenesis whereas none of the other groups showed any significant favorable effect on thermogenesis or any of the other outcome parameters (9). Clearly, more research is necessary as thermogenics remain to be very popular with bodybuilders and the general public alike. Dr. Vukovich presented yet another study comparing the effects of caffeine and ephedrine on resting heart rate, blood pressure, and energy expenditure in eight healthy males. Subjects consumed either a placebo or 150 mg of caffeine and 20 mg of ephedrine after a 12-hour food fast and 48-hour caffeine fast. Participants were moderate caffeine users (150 to 300 mg/day), therefore reducing the potentially confounding factor of introducing a "foreign" substance into their bodies. Following supplementation, heart rate, blood pressure, and energy expenditure were significantly higher than that of the placebo group (11). Anecdotally, users swear by these products; however, one can't negate these important findings—elevated heart rate and blood pressure, compounded with the same effect from intense exercise, could potentially result in negative side effects. On the contrary, other studies have shown these compounds to cause no ill harm; therefore, if you choose to use thermogenics, understand the potential side effects.
Contrary to the anecdotal information many of us hear on a daily basis, here's some legit evidence demonstrating that interval training may be more beneficial than steady-state training, if your goal is overall weight and fat loss (nothing new to T-maggers, if you've been a regular for awhile). Researchers divided 15 obese female subjects into either a steady-state group or an interval training group. Both groups were monitored so they had the same mean intensity, duration, and caloric expenditure (300 kcals) during each workout. This group found that interval training, independent of workload, significantly improved caloric expenditure at a given RER value and, therefore, absolute fat utilization as well (12). To reiterate the point from my last article and what's been said on this site for years, sprinting instead of jogging at a steady pace is ideal for optimal fat loss and total caloric expenditure.
A group from Loma Linda University discussed their study that was intended to measure the effects of different resistance training programs on strength, lean body mass, and metabolism. They used 55 untrained male and female subjects and randomized them into one of three training protocols: group one performed one set of eight exercises, group two performed three sets of the same eight exercises, and the third group performed one set of 24 exercises (intended to introduce variety, as well as high volume). All exercises were performed for 8 to 12 RM and the training protocols lasted for 24 weeks. Not surprisingly, each group improved in each of the parameters assessed (remember, they were untrained). Aside from a potential advantage in the multiple set group in bench press strength, the researchers concluded that there were no clear advantages over one program to another in previously untrained subjects (13).
Ever wonder how maximal power and force are affected over the course of a competitive collegiate football game? Me neither. But this study, or those of similar ilk, may effect an athletes overall performance, so from that standpoint it peaked my interest. The purpose was to examine the changes in force-power production in the leg extensors over four quarters of a collegiate football game. The subjects were either players or non-players, but all were part of the team and participated in the various aspects of the team activities (aside from the game itself, in the case of the non-players). Subjects were tested for jump performance via the squat jump and countermovement jump immediately prior to the game and at the completion of each quarter. The results showed that there was a significantly higher force and power output in players compared to non-players. The initial warm-up period is obviously transient, as the increases in force and power didn't carryover in the non-players as they did with the players who were active the entire game (14). What the heck does that mean for the average gym rat? It means if you hop in the squat rack cold, you'll probably be limited in the amount of iron you can push. If you've been lifting for a while, you probably noticed this a long time ago. Once again, research finally proves what we already knew from experience.
Scientists from Australia presented their work comparing a whey isolate vs. casein through resistance training on strength, body comp, and plasma glutamine. Thirteen subjects were given either 100% whey isolate or casein protein (1.5 gm/kg body weight/day) and were simultaneously under the careful eye of researchers who supervised each workout three days/week. Interestingly, this group found that the 100% whey isolate was more effective at increasing muscle mass (~ 5 kg over 10 weeks) vs. the casein group who gained < 1 kg over the same time period. The whey group was also more effective at increasing strength and decreasing fat mass compared to the casein group. Both proteins seemed to prevent the typical decrease in plasma glutamine levels that are common with exercise (15). These results surprise me as they stand in stark contrast to other whey/casein studies; however, it is what it is and all research should be taken with a grain of salt. In a study out of Shriners Hospital in Texas, researchers assessed the affects of essential amino acids (AA) and muscle-protein recovery from resistance-training exercise. This same group has previously published their data demonstrating the benefits of 6 gm of AA in addition to 35 gm of sucrose on muscle protein synthesis; however, the effect of AA alone remains elusive. Subjects performed a resistance training bout consisting of 10 sets of 10 reps of leg press and 8 sets of 8 reps of leg extension (not sure how they came up with this particular protocol, but that's why it's their study and not mine). Each subject then received 0.087 gm of essential AA/kg body weight. They learned that this supplement stimulated muscle protein synthesis following exercise and arterial EAA (essential amino acid) concentrations increased several-fold following drink consumption (16). In my humble opinion, it would be interesting to compare the EAA head to head with another group who consumes the same amount of EAA, along with 35 grams of sucrose.
That about wraps up my week long stay in St. Louis, unless you want to hear about my enjoyable twelve-hour departure, which started with lines that were too long in the airport and ended with me boarding a flight six hours later than the one I scheduled. I guess the last tidbit of information I learned was to always pack plenty of "just in case" snacks, because I was able to feel my muscle catabolizing by the minute and cheesy St. Louis airport food wasn't cutting it. Geez, the things I go through to bring you guys the latest studies. Hope you learned something!
Christopher R. Mohr, RD, is a Masters Candidate in Nutrition Science at the University of Massachusetts, Amherst. Because of his traumatic experience at the airport, he was given combat pay for this article and awarded the Purple Testicle for bravery in the face of catabolism.
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