A delightful gentleman by the name of Scrawny McSkinny sent me this question:
“For my entire adult life I have weighed 136lbs. Wether I eat more or less, cheese quesadillas from Taco Bell or hearty salads, it makes no difference. I think I am physically incapable of altering my body weight. I believe it is due to my ultra high metabolism. Without radioactive juice and an x-ray machine, I can’t be sure, but sometimes I think I’m pooping out my breakfast just before lunchtime. I would like a hot six pack and some man tits. What should I do?”
My most esteemed Mr. McSkinny, if only you knew the number of unholy acts I’d perform in order to have your problem. Still, as temptingly easy as it is to characterize your inability to gain weight as an “ultra high metabolism“, the truth is that this is a major oversimplification of the many complex processes involved in energy intake, storage, and output. Kick back and relax while I treat you to a very brief overview containing actual science:
Metabolism includes catabolic processes, which break food or bodily components down for energy; and anabolic processes, in which the body “builds up” and synthesizes components like muscle proteins or stores energy as glycogen or adipose (fat). Essentially, your body takes the protein, fat, and carbs from your diet and, through digestive mechanisms, breaks them down into their respective monomers: amino acids, fatty acids, and monosaccharides. Most typically, glucose (a monosaccharide) is used by the cell to generate ATP, which is a molecule with lots of stored energy that the cell uses to fuel all of its other biochemical reactions (or all of the various things that your cells do to make you, uh, live.) Other monosaccharides (like fructose), fatty acids and amino acids may also be used by the cell to generate energy, or they can be used as building blocks to construct needed materials, such as contractile proteins for muscle fibers (hint hint) or phospholipids to be incorporated into the cell’s membrane. The body uses many complex regulatory mechanisms (including hormones and biochemical feedback systems) and metabolic pathways to determine the fate of the substances that you ingest, and if this topic fascinates you then I highly recommend a course in organic chemistry or biochemistry.
My point here is that the picture gets really complicated, and much of this stuff is probably genetically determined. You have your own unique genetic profile, and if you’ve been 136 lbs. your entire adult life, you will probably never look like this, no matter what you eat. But the good news is you can still improve your health, increase your fitness and develop your body’s version of a six pack and “man tits” through lifestyle modifications like diet and exercise (I’d like to add a “duh” and a friendly but pointed eye-roll here).
You mentioned that you’ve toyed with your diet without results, but for you, I’m suspecting that exercise is the missing component. If you have not considered this, then you have bigger problems than the meager size of your deltoids. Furthermore, even if Taco Bell cheese quesadillas did help you gain weight, increasing your caloric intake without increasing your physical activity will only lead to fat gain. If increasing caloric intake alone was sufficient to build lean body mass (i.e. muscle), we’d have a body-builder epidemic here in America instead of an obesity epidemic. Perhaps your body is extra talented at burning energy for fuel, but not so concerned with storing fat or building muscle. This means that you will have to make a REALLY good argument to convince your body to bulk up. The human body, you see, is very energy efficient and is not likely to waste calories maintaining something it’s not using–better to feed glucose to the brain for math problems, or make a bunch of extra sperm for that reproductive edge, or generate lots of heat for those cold northern European nights, or use the your energy doing whatever would serve you better than maintaining accessory muscle, since the body doesn’t really know the difference between something that’s unused and something that’s useless. All of the muscles in your body are being remodeled at all times to match the functions that are required of them, which means you have to engage your muscles in a way that forces them adapt to the new demands being placed on them if you want them to be remodeled into rippling abs and bulging biceps (Guyton & Hall, 2006). Muscles do not grow via cell division (hyperplasia), but rather by increasing the diameter, length, and contractile elements (proteins called actin and myosin) of each individual muscle cell (Guyton & Hall, 2006). This process, in which a cell increases its size, is called hypertrophy. In order for hypertrophy to occur, the muscle must be loaded (either by weight or resistance) during contraction. Though we don’t know the exact mechanisms by which muscles “sense” the demand placed on them, we do know that muscles develop increased vascular supply, increased number and size of myofibrils (bundles of actin and myosin), and increased enzyme systems that supply energy (like glycolysis, which is a metabolic pathway that breaks up glycogen molecules into glucose molecules to provide a rapid energy source during short-term forceful muscle contraction) during the hypotrophy process (Guyton & Hall, 2006). We know that properly trained muscles can experience noticeable hypertrophy within 6 to 10 weeks, and that contractile proteins will decay in unused muscle and the muscle will atrophy (Guyton & Hall, 2006).
Now, I won’t go and outline a workout plan for you. I used the Body Sculpting Bible for Women by overdeveloped hunks Villepigue and Rivera to help me put together my weight lifting routine when I started strength training five years ago. Here’s a website that provides resources related to the Body Sculpting Bible for Men if you are on a budget and prefer the DIY approach. Start slow and mind what they say about proper form, you hear? If you’d like more motivation and a routine that suits your specific needs, I’d suggest investing in a good, reputable and experienced personal trainer to get you started on your path to healthy weight gain. Other activities like rock climbing may be more appealing to you. And don’t forget the cardio–heart health is more important than looking suave and, besides, extra overlying fat will obscure your hot new muscles and diminish the appearance of your muscle tone. Additionally, you’ll have to fuel your workout with foods that promote lean body mass, so you should choose nutrient dense foods that meet your caloric need. You’ve probably heard all of this before, but unprocessed plant-based foods like green leafy vegetables, root vegetables, and whole grains alongside plant-based proteins or animal-based lean proteins are your best bets. I like a lot of the nutritional and cooking tips in Men’s Health Magazine.
If you commit to a proper weight-training program and muscle-building diet for over two months and see no results, it probably means you’re doing the exercises wrong or not eating enough. If these problems are ruled out, it’s always possible that your thin physique is the result of something more insidious, like a gastrointestinal problem that inhibits your ability to digest or absorb nutrients, or a hormonal imbalance like hyperthyroidism. It’s a good idea to be examined by a doctor before initiating a new exercise program anyways (especially if you’re older), and you should visit your doctor if you experience any complications like exercise-related chest pain or injury.
A few more tidbits to motivate you:
Resistance training and dietary protein help prevent age-related loss of skeletal muscle mass and function (Campbell & Leidy, 2007).
Being underweight or obese at any point during adulthood is associated with lowered cognition in late midlife (Sabina et al., 2009).
Increased lean body mass is correlated with increased bone mineral density, and high-impact aerobics like running combined with resistance training offers the best skeletal protection (Rector et al., 2009).
With this, and the thousands of other studies demonstrating the benefits of exercise, I rest my case.
Cambell, W. W. and Leidy, H. J. (2007). Dietary protein and resistance training effects on muscle and body composition in older persons. Journal of the American College of Nutrition, 26(6), 696-703.
Guyton, A. C. and Hall, J. E. (2006). Textbook of medical physiology (11th ed.). Philadelphia: Saunders.
Rector, R. S., Rogers, R., Ruebel, M., Widzer, M. O., and Hinton, P. S. (2009). Lean body mass and weight-bearing activity in the prediction of bone mineral density in physcially active men. Journal of Strength and Conditioning Research, 23(2), 427-435.
Sabina, S., Kivimaki, M., Shipley, M. J., Marmot, M. G., and Singh-Manoux, A. (2009). Body mass index over the adult life course and cognition in late midlife: The Whitehall II cohort study. The American Journal of Clinical Nutrition, 89, 601-607.