After being steeped in the fitness industry for over a decade, I've seen many fitness fads come and go, and I've also seen many fitness myths dispelled. But there are still a few myths floating around among personal trainers, believed by exercise enthusiasts and found in those fancy fitness magazines in gyms and health clubs, myths that could be holding you back when it comes to building muscle. So in this episode, you're going to discover the current top three big muscle-building myths.
Myth 1: You need to lift heavy weights to build muscle
It's certainly true that an excellent way to build muscle is by lifting heavy weights with big compound exercises such as squats and deadlifts. But it's not the only way to go. Contrary to popular belief, you can gain muscle using light weights (or body weight) and higher reps.
For example, one study compared the effect of high reps and low reps on muscle growth, comparing sets performed with 80 percent to complete muscle fatigue with sets performed to 30 percent to complete muscle fatigue. It turns out that the load is not important, but simply whether or not a muscle is actually worked to fatigue, and in this study, high reps and light weights stimulated just as much muscle growth as low reps and heavy weights. So yes, this means you can, for example, build chest muscles by skipping three sets of eight reps on a bench press, and instead doing a few sets of high-rep push-ups to complete failure (which is good to know if you're stuck working out in a hotel room or living room, have no access to a bunch of steel, metal, and weight plates, and still want to build muscle!).
There are plenty of other studies that back up the muscle-building capabilities of high-rep, low-resistance training. In this study, light super-slow lifting at 55-60 percent of the participants one rep max (1RM) increased both muscle thickness and maximal strength just as much as heavy normal-speed training performed at 80-90 percent of 1RM. In this study, both heavy training with 8-10 reps and light training with 18-20 reps activated the genes involved in muscle growth.
Another study found that training with higher reps and lighter weights (25-35 reps) led to the same gains in muscle size as heavier weights with 8-12 reps. Even in seasoned weightlifters, researchers found the same muscle growth occurs when comparing 20-25 reps weight compared to 8-12 reps with a heavy weight.
In this study, high reps and light weight (24 reps with 30 percent) increased post-workout protein synthesis, a sign of muscle building and hypertrophy, for 24 hours after exercise, and it did this to a far greater extent than low reps and heavy weights using 5 reps and 90 percent. In yet another study, low weight training, even when not performed to complete muscular fatigue, stimulated protein synthesis (a sign that connective tissue is better capable of repairing) in connective tissue just as much as heavy weights.
Ultimately, if you want to add muscle mass as fast as possible, lifting heavy weights is the way to go. But you can still build muscle with light weight and high reps. Incidentally, as this study and this study shows, this approach seems to be most effective when training the legs vs. the upper body.
Myth 2: You need carbs to build muscle
Many folks trying to pack on muscle have been told that the muscles need storage glycogen and ample amounts of carbohydrates to grow. However, a recent study (albeit on rats) shows that this may not be true. In the study, researchers compared a ketogenic diet comprised of 20 percent protein, 10 percent carbs and 70 percent fat with a typical Western diet of 15 percent protein, 45 percent carbohydrate, and 40 percent fat.
It turns out that after a six week ketogenic diet, rats were just as capable of producing all the biochemical parameters associated with anabolism and muscle growth. And yes, while these were rats being exposed to electrical muscle stimulation and not weight training humans, you can certainly delve into an "N=1" example with a human subject by reading my article "Can You Build Muscle On A Low Carbohydrate Diet" or by visiting a website such as Ketogains.com (which I am not in any way affiliated with!).
Myth 3: You Need To Lift Weights To Maintain Muscle
The prevailing thought among exercise enthusiasts is that if you lay off weight training for a certain period of time, then you will lose muscle, and that the only way to maintain muscle is to load that muscle.
But there are other ways you can maintain muscle, even if you're injured and can't make it into the weigh room. One such method is electrical muscle stimulation (EMS), a topic which I cover in detail in this article.
However, another lesser-known method of maintaining muscle is via heat stress, which you can implement by using a dry sauna, wet sauna or infrared sauna. One of the mechanisms by which heat stress prevents muscle loss and protein degradation is by triggering the release of proteins called heat shock proteins (also known as HSPs). HSPs can prevent muscle damage by removing free radicals and supporting cellular antioxidant production, but can also repair misfolded, damaged proteins in muscle tissue. Research has shown that when rats are exposed to heat stress, they expressed HSP's to an extent associated with 30 percent more muscle regrowth compared to a control group. As an added bonus, one particular HSP (the HSP70 gene) has also been linked to increased longevity, which suggests there may be anti-aging benefits to regular heat stress too!
Growth hormone is also crucial for repair and recovery of muscles, and research has shown that two 20-minute sauna sessions separated by a 30-minute cooling period can elevate growth hormone levels two-fold over baseline. Two 15-minute sauna sessions at an even warmer temperature separated by a 30-minute cooling period resulted in a five-fold increase in growth hormone.
It is also important to note that when hyperthermia and exercise are combined, they induce a synergistic increase in growth hormone, which is why I do yoga, push-ups and squats in my infrared sauna, a practice that I outline in detail here. For an additional recovery benefit, sauna also increases blood flow to the skeletal muscles, which helps to keep them fueled with glucose, amino acids, fatty acids, and oxygen, while removing by-products of metabolic processes such as lactic acid and calcium ions, and can even build new red blood cells at a rate similar to illegal performance enhancing drugs such as EPO.
Finally, I'll readily admit that when it comes to building muscle fast and maintaining muscle, there really is no substitute for simply lifting heavy stuff and stuffing your face with sweet potatoes. However, if you have exercise equipment, dietary or injury limitations, it's nice to know that you can also build and maintain muscle with strategies such as a body weight or low weight training, a low-carb or ketogenic diet, and the use of electrostimulation or sauna.
If you have more questions or comments about these muscle-building myths, then leave your comments below!