Saturday, June 13, 2009

Lonnie Lowery, Ph.D. - Cutting-Edge Muscle Science

A great recap of some recent conference happenings from Dr. Lowry, writing over at T-Muscle (formerly T-Nation).

Cutting-Edge Muscle Science


If you're involved in exercise or nutrition research, you know that spring and summer are peak seasons for scientific conferences. This is when people like me shed our lab coats to go out and listen to people like us talk about what we've done while wearing those lab coats.

At the best conferences, professors and students from around the globe gather to hear renowned experts, including Nobel laureates and industry icons, offer insight into the research that will someday change the way we eat, train, and live. The best moments remind me of why I became a scientist in the first place.

But even at those events, the really juicy information is interspersed with lectures that would cure a room filled with insomniacs. I sit through it all — the fascinating and the coma-inducing — so you don't have to.

This article looks at the best information I picked up at two recent conferences — the stuff that keeps me awake at night thinking of all the possible applications and implications.

Tour de Lonnie, Part One

This trip started with a look at the national weather map. There was a heavy green line of stormy precipitation on radar that sat conveniently along my flight path down to Texas. Brilliant. I hate bumpy, white-knuckled flights, and I hate fiery plane crashes even more. Nonetheless, after a brief appearance at the lab to make sure no one was having a meltdown, I headed for the airport.

About eight hours later, after a roundabout flight in which the passengers bounced around like popcorn, I arrived, exhausted, in Dallas. It was cold and clear and I was happy just to be on terra firma. Another short flight and midnight cab ride later, I was in Wichita Falls, Texas, home to Midwestern State University, and the convergence point for some scientific heavy hitters at the annual meeting of the American Society of Exercise Physiologists.

Here's a Cliff's Notes report on some of the talks.

Clench your jaw, boost your bench press

Concurrent activation potentiation — CAP — is an esoteric topic, but it's probably the one that TMUSCLE readers would find most interesting. Simply put, it's a non-dietary type of ergogenic aid.

Some of you are probably aware that the performance of prime-mover muscle groups can improve when seemingly unrelated muscles are purposefully contracted. On TMUSCLE, several articles have recommended one form of CAP: deliberately intense gripping. (This one is a recent example.)

Research has shown that various forms of CAP — aggressive gripping, jaw clenches, and core activation (such as the Valsalva maneuver) — can boost performance by roughly 15 to 20%.

The focus of this presentation was a recent study that looked at training status. Would experienced guys differ from neophytes? The results indicate no correlation between training status and performance enhancement from CAP. Peak forces and rate of force development were improved similarly for all involved.

Interestingly, women benefit less from CAP. The reason is open to speculation. Perhaps women are socially indoctrinated away from severe facial squinting, jaw clenching, and breath holding.

Personally, I'd say that depends on the woman.

How to prevent ACL injuries

Speaking of women, I'd been aware of the fact that female athletes were at much greater risk for anterior cruciate ligament injuries. But I had no idea of the magnitude: Women are six times more likely than men to have an ACL injury, which represent 69% of all knee injuries suffered by female athletes.

The most often-mentioned culprit is the quad dominance of female athletes. Their quadriceps tend to be much stronger than their glutes and hamstrings, and that imbalance puts their knees at risk.

This study evaluated the effects of a six-week lower-body training program that prioritized hamstring training. The goal was to enhance hamstring versus quad activation and timing in "ACL-risky" movements.

The result? Compared to controls, subjects who resistance trained had higher ham:quad activation ratios during drop jumps and sprint-and-cut tests. No differences in timing of muscle activation were noted. The researchers from Marquette University concluded that hamstring-prioritized training may promote knee stability and reduce injury rates for women.

Why Johnny can't run

Another interesting session focused on the inadequate state of physical education in schools. Declines are multi-faceted, including time devoted to gym class, student-to-teacher ratio, facilities, and teacher training.

This talk mostly concerned teacher preparation. The presenters shared a 2007 survey of licensed physical education teachers, which revealed that only 65% had a basic understanding of topics like power, metabolic responses to exercise, strength training, and even body-mass index (BMI).

In other words, the average TMUSCLE reader might very well understand exercise physiology at a more sophisticated level than a substantial minority of today's professional phys-ed teachers.

A lively discussion followed on the educational equivalent of the chicken-and-egg question: Is it better to have an expert teacher with less knowledge of the subject matter, or a true master of the material with less teaching experience?

In the end, it was generally agreed that kids would be better off learning from a true expert than an expert pedagogue.

When potty language doesn't enhance one's argument

There was also a series of talks from the CrossFit people. You've read a lot about CrossFit on TMUSCLE (here and here, for starters), so the relative merits have been beaten to death.

I'll summarize these sessions by saying that a number of scientists I spoke to were left wanting some hard references in the form of published research. Motivational anecdotes and arguments are interesting, but evidence-based practice requires peer-reviewed evidence.

I don't disagree with the general premises presented by the CrossFit folks, but I was left with lingering questions about the increased potential for injury and a possible devaluation of sport-specific training. Then there's the question of uniqueness. Several faculty members and doctoral students expressed concern that the CrossFit "phenomenon" is really just an attempt to brand generalized conditioning and already-employed principles like power output (work divided by time).

On top of that, the F-bombs and other expletives dropped by the CrossFitters didn't go over particularly well in a room filled with scientists and academics.

That said, I was impressed by the no-nonsense (and ultimately published) information shared by Mark Rippetoe, the subject of this TMUSCLE interview. I like that he was willing to challenge convention by pointing out that things like periodization may not be universally necessary.

Speculation works much better once you've paid your dues

The keynote lecture by Kary Mullis was similar to the CrossFit presentations in one sense, but completely different in every other way. (No F-bombs, for example.)

Mullis is a Nobel laureate (chemistry, 1993); his claim to fame is inventing the polymerase chain reaction, which has been described as one of the monumental scientific techniques of the 20th century.

His talk was about scientific paradigms — he calls them "plausible fables" — and how we need to stay flexible in the way we cling to them. His tutorial was beyond the mere boundaries of scientific or historical literacy; to my geekish delight, he ran the gamut from Ptolemy's Earth-centered universe, to the fallacy of living in three dimensions, to the Big Bang, to the lipid theory of heart disease.

With regards to the latter, he has voluntarily stopped taking his cholesterol-lowering statin meds, in part due to emerging data on bacterially based plaque disruption. If bacteria are responsible for causing arterial plaque to break away from the walls of blood vessels and clog arteries, then the traditional idea that gradual accumulation of plaque causes heart attacks goes out the window. He also expressed a half-joking concern that low cholesterol concentrations would make him "dumber."

There was much more, and maybe someday I'll write about it. But here's the most important lesson to take away: The type of flexibility Mullis described is best employed after one pays his dues with years of study ... something I wish the CrossFit folks would take to heart.

Protein + lifting = stronger bones

The nutritional talk of the day came in the form of a "distinguished lecture," presented by a well-dressed, articulate, and devilishly handsome bald guy.

My talk focused on bone-density data from long-time lifters with a penchant for protein. I used the example of lifters who've consumed an average of 195 grams of protein daily for 22 years. These guys have significantly denser bones than counterparts who don't go out of their way to take in extra protein. They also have no reliable differences in gross kidney function or damage, nor do they appear to lack fiber in their diets.

This, of course, is 180 degrees from what we currently teach about sports nutrition: supplemental protein isn't necessary, it's bad for your kidneys, you'll be constipated ...

It really is amazing how little population-specific research exists on this subject, which is central to all true muscleheads. I hope that these data will become part of the discussion, so the next time a bodybuilder asks an expert how much protein is too much, a clear and scientifically valid answer can be given.


Tour de Lonnie, Part Two

Two weeks after the Texas meeting, I hit some talks in Wisconsin that were more specific to strength training and muscle building.

High protein intake: is it safe?

Dr. Bill Ebben of Marquette University invited me to participate in their annual lecture series. Since previous speakers in the series included such heavy hitters as Jeff Volek, I was excited to be included, and a little nervous about speaking in front of more than 150 people, which is about as big a crowd as I've addressed.

My topic was, once again, protein safety, this time focusing specifically on kidney health. I can summarize by saying that using standard clinical measures — blood work, microalbuminuria, and creatine clearance — there's no reason to be concerned about protein-seeking weight lifters when compared to other lifters who don't bother with purposeful protein. Although there've been two fairly small studies on this population before, we're examining a much longer duration (mean of 10.1 years so far) and a higher protein dose (mean of 250 grams per day).

It's worth pointing out, as I did to the audience, that our work is not an attempt to encourage gigantic protein intakes, which are largely wasteful. Nor is it "proof" (research never is) that all imaginable doses of protein are without consequence, regardless of duration. All we can say is that with some well-accepted but less than super-sensitive testing, there doesn't seem to be any overt renal damage over a decade or so, despite some pretty big intakes.

Frankly, I wouldn't expect to see big problems if someone were to come along and push the envelope even further. But that's just conjecture, based on what I've read and observed. Maybe future researchers looking at microscopic histological changes will find something. But even if they do, I have to wonder how relevant and applicable that information would be, considering that we can't see much damage with the standard markers we're using today.

As always, I have to believe that more time and more data will give us more definitive answers.

Make no bones about it: lifting makes them stronger

After a night of surf, turf, and Shiraz, I headed up the road to Oshkosh for the National Strength and Conditioning Association's Wisconsin state clinic.

In the first talk, a student shared data on the best ways to gain bone density and bone strength with weight training. Traditionally, we've assumed that total mechanical tension is most important, but new data shows that the rate of loading also matters. Faster development of loading means better stimulation of bone growth.

Here's something else I didn't know: We now have data on how much rest is necessary for bone cells to re-sensitize for further growth. It appears that eight hours is sufficient for some osteogenesis to again occur from a successive bout, but it takes 24 hours to achieve a 98% return of mechanosensitivity.

I should mention that the bone remodeling doesn't just occur at the places where the tendons insert. New bone tissue accumulates along the midpoints of long bones, such as the femur, where tension is also high.

For optimal bone growth, you want to include back squats, leg presses (depending on the machine type), deadlifts, and freestanding upper-body exercises. Plyometric movements and Olympic lifts are also recommended, since those offer the highest rate of force development. You want to use a minimum of 65% of your one-rep max, and limit total rep counts to 50 per exercise per workout.

Turning a tortoise into a jackrabbit

I got a rare opportunity to see the famous Vern Gambetta talk on the subject of speed. Cool tidbits he offered were:

• Speed is a biomotor ability we all have to some extent. In other words, speed is a learnable motor task, and we can all get pretty fast if we work at it.

• Track speed doesn't equal game speed. That's why speed drills should be task-specific, and track work should be limited.

• Optimal speed drills should approximate game situations and last four to six seconds.

• Don't practice "speed in the air" (e.g. skipping) when your game time is spent on the ground.

• Surprisingly, many athletes today are actually too fast for their game, and multidirectional agility suffers as a result.

The Finish Line

There was a lot more where that came from, but I think I've offered you the best of the best information I picked up during my two weeks of speaking and listening to my fellow speakers.

The most important take-away lessons:


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