Sunday, August 15, 2010
Exercising with light weights is good for you
If you are a regular reader of my blog, you know that I advocate incorporating a "smart" exercise program into your daily routine. I have found a regular program offers significant benefits over not exercising or an occasional exercise regime. The other day a came across a research paper on the type of weight exercise a person should perform. The first link here is a summary, while this second link is a detailed report of the study. This study was interesting, because my wife has been telling me this for years.
"Background: We aimed to determine the effect of resistance exercise intensity (% 1 repetition maximum—1RM) and volume on muscle protein synthesis, anabolic signaling, and myogenic gene expression."
What this means is that they were trying to determine what type of exercise program is better for building muscles, heavy weights or light-weights with more reps.
"Conclusions/Significance: These results suggest that low-load high volume resistance exercise is more effective in inducing acute muscle anabolism than high-load low volume or work matched resistance exercise modes."
Or, for a better explanation:
"Current gym dogma holds that to build muscle size you need to lift heavy weights. However, a new study conducted at McMaster University has shown that a similar degree of muscle building can be achieved by using lighter weights. The secret is to pump iron until you reach muscle fatigue."
Stuart Phillips, an associate professor of kinesiology (the Science of Human Movement focusing on physical activity) at McMaster University, had this to add. "We're convinced that growing muscle means stimulating your muscle to make new muscle proteins, a process in the body that over time accumulates into bigger muscles."
Dr. Phillips went on to say,
"... the project that showed it's really not the weight that you lift but the fact that you get muscular fatigue that's the critical point in building muscle. The study used light weights that represented a percentage of what the subjects could lift. The heavier weights were set to 90% of a person's best lift and the light weights at a mere 30% of what people could lift. It's a very light weight, says Phillips noting that the 90-80% range is usually something people can lift from 5-10 times before fatigue sets in. At 30%, Burd reported that subjects could lift that weight at least 24 times before they felt fatigue."
He then summarized the significance of the findings.
"We're excited to see where this new paradigm will lead," says Phillips, adding that these new data have practical significance for gym enthusiasts but more importantly for people with compromised skeletal muscle mass, such as the elderly, patients with cancer, or those who are recovering from trauma, surgery or even stroke."
BNet explains what muscle protein synthesis is and why it is important. "Muscle buildup is technically known as muscle protein synthesis. This involves the assembling of amino acids into the proteins that make up muscle fibers. Muscle breakdown involves the removal of amino acids from these proteins. Most bodybuilders make the mistake of focusing only on muscle buildup (synthesis) by using supplements that primarily boost protein synthesis. Yet impeding muscle breakdown, technically known as catabolism, is just as important as increasing muscle protein synthesis. That's because muscle growth occurs only when muscle protein buildup increases at a greater rate than muscle protein breakdown. To mix our metaphors a bit, a good analogy is a brick wall, where the bricks symbolize amino acids. If you add three bricks to the wall (protein synthesis) but five bricks fall off (catabolism), the wall gets smaller. If you add five bricks and only three bricks fall off, the wall gets bigger."
Now, we know that no one living with Kennedy's Disease should exercise to a point of muscle fatigue because it is believed to accelerate muscle wasting. At the same time, we know that some regular stimulation of the motor neurons and muscles is actually healthy and helps retain muscle memory. Two physical therapists that I have worked with also recommended the need for developing a program that included aerobic and light weight lifting exercises. They both commented that under normal circumstances (i.e., someone exercising that does not have the defective gene) a person should perform a more aggressive exercise program. However, for someone with the defective gene, they recommend a more, dare I say, "enlightened" approach (do no harm).
That being said, they were both talking about someone (me) in the late fifties and early sixties where the progression was quite noticeable. When I was in my twenties and thirties (and even into my early forties), I pushed myself pretty hard. I do not regret enjoying life to the fullest in those days because you only live once. Now, I hope I am a little smarter and do no harm.
I would like to hear about your exercise program. Do you feel it benefits or hurts you?