Muscles: Such Stuff as Dreams Are Made Of

You've gotta shake your head in awe and wonder when you realize what muscles do, either when going about the regular tasks of daily life or exercising at your limits.

Truly one of the great miracles of life is how chemical energy, stored in our bodies as glucose or fat, is converted into power and motion - lifting, running, catching, kicking, throwing, etc. To accomplish these, our bodies have multiple energy systems at work, often simultaneously.

To move, muscles must contract, which requires what is called adenosine triphosphate (ATP). When a single phosphate molecule breaks away from an adenosine molecule in the muscle cell, energy is released that causes a muscle to contract. Each time this happens, another phosphate molecule must replace the previous one for the muscle to contract again. That phosphate must come from delivered from outside the cell. The harder and longer we exercise, the more ATP is needed. When you run out of ATP, you stop moving.

Depending on whether you are jogging slowly or sprinting hard, a different energy system will perform the job of providing the phosphate to form ATP. If you're jogging slowly (aerobic), you use oxygen with glucose or fat. If you are doing high intensity exercise (anaerobic), you will use creatine phosphate for a few seconds, then switch to pure glucose, which won't last much longer than a few minutes.

Few of us, even in our most intense workouts, ever discover the limits of our energy systems because if we push our muscles hard enough, our willpower surrenders to the the burning sensation caused by the buildup of lactic acid and we slow down or lower the barbell. On rare occasions, such as shown in the video below, we reach our chemical boundaries, sometimes in ways that are admirable and comic at the same time. You can also learn a lot about how muscles work by watching someone, like these triathlon competitors, enter the twilight zone of muscle failure.

What you just saw was somenne who can no longer deliver phosphate to the ATP in their muscle cells. The commentator is wrong that the person has run out of calories. The energy is present in the body, but in forms that can no longer be delivered and converted fast enough. Actually these women were probably starting to produce glycogen by metabolizing their own muscle tissue through a slower process called gluconeogenesis, a last ditch effort by the body to respond to signals from the brain to get fuel to the muscle cells. But it's too little, too late. The people who finished ahead of them, through a combination of genetics and training, were able to keep their energy flowing.

What's also interesting to watch is how the body naturally recruits other muscles to accomplish a task that muscles usually used in the task can no longer perform. If you are trying to open the tight lid on a bottle of ketchup, sometimes you cannot do it just with an easy twist of your fingers, but must enlist your hardest grip and the action of your forearm muscles. Often when you watch the finish of a running race, you'll see people running in abnormal or awkward ways, throwing their arms side to side or lifting their hips to pull their legs forward. When one set of muscles fail, another set will come forward to try to get the goal accomplished. In the case of the video, these womens' leg muscles were depleted of ATP, but they were still able to recruit their fueled upper bodies, still rich with ATP, and crawl to the finish.

Shakespeare was right: we are such stuff as dreams are made of.

Seeing Red

As every sentient omnivore must know by now, red meat got butchered by the media last week. Unfortunately, it only further confuses a public in desperate need of information on what they should eat to improve their health as more Americans become obese and rates of chronic disease skyrocket.

The first story was a bona fide expose that 70% of the ground beef for sale in the local grocery store has been adulterated by "pink slime," a filler made from fat and other debris left on the killing floor in the meat processing plant. The concoction is put through an industrial process to remove some of the fat then gassed with ammonia to sterilize it.  In a comic display of corporate doublespeak, a meat industry spokesperson made the rounds on national television to say with a straight face (with no hint of humor or deception) that pink slime is beef. Nobody was fooled.

Then a second  meat blockbuster blared from every major TV station and newspaper because of the severity of the claim: The Harvard School of Public Health announced that people who eat red meat are shortening their lives by years!  What this study really proves is that Harvard's stature as a credible source of information for national policy debates on health and nutrition should itself be studied. Harvard's study is to legitimate scientific inquiry what pink slime is to beef. Read these excellent critiques of the Harvard study by Gary Taubes (warning: it's long but worth it) or Denise Minger at Mark Sisson's website.

What I find most intriguing and absent in the Harvard study is that it ignores multiple questions about all red meats that so many of us consume, which are tainted with growth hormones, antibiotics, and other additives. And what about corn? The industrial ag feed lots force cattle to fatten up fast with corn so they can be turned into $. Unfortunately, corn is a grain that a cow's their ruminant GI system is not designed by nature to digest. As a result, vital nutrients such as Omega-3 fatty acids are diminished while excessive saturated fats are increased. The USDA says not to worry, but more and more people do not believe them any more than Harvard University.

A TOJ always tries to keep an open mind. Right now there's a paradigm fight underway between the meat eaters in one corner, represented by the Paleo and Primal crowd, and the vegetarians, represented by Dr. Dean Ornish and former president Bill Clinton, in the other. It's possible that there's something in meat, especially if it's eaten in excess, that is harmful to our health. Dr. Gabe Mirkin provides an interesting bit of scientific speculation about a molecule called New5Gc that was discovered by Ajit Varki of the University of California and included in the Proceedings of the National Academy of Sciences in 2003. Spooky.

However, this TOJ will continue to eat red meat, mostly organically grown and grass fed, and not-charred. Red meat is rich in amino acids and B-vitamins. Your muscles need to be fed with high quality protein, despite what Harvard or the USDA have to say about it. Living long is great, but first and foremost you want to live well.

A Little Fortius

For many of us, the journey to fitness is a never-ending. Even people in very good shape in terms of body composition, endurance, flexibility, and strength, will for some reason, feel they need to do more. Sometimes it's to avoid boredom with the same exercise routines. But just as often it seems there's just a constant drive to do more. It's like we become obsessed with the Olympic motto: Citius, Altius, Fortius, i.e., Faster, Higher, Stronger.

A very good female friend asked about doing upper body work with a barbell. Although she's plenty fit and does cardio and resistance several times a week, she's been reading some materials by body builders and is curious about standard exercises with the barbell, such as dead lifts, squats and presses. Some of her interest is driven by a desire to further strengthen her upper body (maybe a little to get a little more buff looking) and add variety to her workouts.

She's works out routinely and effectively with dumbbells, mostly high rep endurance exercise. Now she's started doing some low rep deadlifts and thinks about doing the same with presses. There are some specific benefits to pressing a barbell, but most of the benefits can also be realized with safer exercises like push ups. True, you can get stronger lifting more than your body weight, but who needs to be that strong?

My friend is a TOJ. The main reason I wonder about her getting wanting to lift significant weight on a barbell is because there is a much higher probability for injury. Lifting a weight overhead can invite shoulder or back problems if the joints aren't already strong and stable. The problem with either a shoulder or back injury is that they don't just slow your journey to fitness, they can bring it to a frustrating and permanent halt.

She's already in great shape and will do it if she decides to. Maybe she can start with just the bar with no added and see what it feels like, if pressing the bar recruits muscles she feels need more work. Or maybe she'll discover she's already doing plenty of good resistance exercises with calisthenics, straps, kettlebells and dumbbells.

Exercise is too fun and important to our health to put at risk. Whenever taking on a new challenge, ask why you're doing it and be honest about the risk. If you decide to go for it, be guided by a modified Olympic motto: A Little Faster, A Little Higher, A Little Stronger.