For many young athletes, building muscle and gaining weight can seem like an impossible challenge, but with a few smart strategies, it is possible to get bigger and stronger.

Some people naturally have a smaller appetite, a faster metabolic rate, are training too much or too little or are simply more active throughout their everyday life than they even realise.  By tracking these variables, we can take out a lot of the guess work and find the true reason/s why one may be struggling to obtain the muscle mass that they are seeking.

How to build muscle for skinny guys: the smart guide


Calorie intake

The number one most important variable for gaining weight and muscle is the caloric balance between what we burn and what we take in.  In order to track this, we first need to take a look at what we are really taking in.  Recording a food-log for 3 days is usually sufficient in taking a snap shot at our eating habits.  Then either by hand, or with several of the apps and online tools, we can see a good estimate of the number of calories as well as macro-nutrients (protein, carbohydrates, and lipids) that one is taking in each day.  I have found that almost everyone is eating a lot more, or a lot less than they first believed.  For example, a under-weight individual may think they are eating plenty of food in a day, and that their inability to build muscle is simply due to poor genetics or some problem with his/her hormones, but in reality, he is eating <2000 kcal/day while also biking to and from work and training for 10 hours/week.

(Why not take ALL guesswork out by following a Muscle Maxx muscle building diet plan, designed by a dietitian?)

Once we find what their current caloric intake is, it’s as simple as adding additional calories.  Of course, we want to be measured in this approach as an all-out bulk (adding tones of additional calories) is not a smart strategy in the long term.  You see, no matter how hard one trains, or how many grams of protein one ingests, the body can only synthesize so much lean mass before the extra kcals and nutrients are stored as fat.  Gaining extra body-fat, although usually not a huge problem for a skinny person, over time will decrease insulin sensitivity and eventually make it harder to both build muscle, and to loose fat.  This is why it is suggested that a lifter weigh themselves a few times/week and aim for a gain of 2-3 pound of weight gain each month.  Anything over this is nearly guaranteed to lead to a high amount of fat-gain.

Calorie sources

We also need to pay attention to where the calories are coming from.  Of course, we need a relatively high amount of protein, but it’s important to note that protein intake over 1.5-2g/kg of lean mass is essentially wasted and that having a high protein diet is actually more important when “cutting” in order to maintain muscle mass on a caloric deficit.  For gaining weight I usually recommend a macro-nutrient break down that is relatively balanced, with a starting point of about 40% carbs, from mostly complex sources such as vegetables, low glycemic fruit (berries, apricots, etc…), tubers (yams, sweet potatoes, purple potatoes etc…), rice and quinoa.

Fats which often get a bad rap, should a lot be kept relatively high at around 25-30% of the kcal intake which is quite easy to do since they are much more calorie dense then carbs or protein (9 kcal/g for fats vs 4 kcal/g for protein or carbs).  The best sources of fat in the diet include omega-3s from salmon, sardines, grass-fed beef and wild game, poly-unsaturated fats from sources like olive oil, nuts and seeds, and finally saturated fats from high quality meats, coconut oil, red-palm oil (my personal favorite) and real butter.

The final macro-nutrient, protein will make up the final 30-35% of the diet plan, which is really quite easy to do once you include a high-quality whey; or if one has a dairy allergy, plant-based shake after each training session.  Besides shakes (which should be kept to a minimum, due to their strong ability to spike insulin, the best souses of protein will always be animal products – they have a much more complete breakdown of amino acids are better utilised vs plant sources) such as meat, poultry, fish, and whole eggs (tons of nutrients and kcals in the yolk).  This break-down is usually very effective as long as the athlete is training hard, and eating a caloric surplus of at least 250kcal/day, a high percentage of the weight gained should be lean-mass.

A diet like the one above should be fairly complete, but occasionally one may have trouble getting enough kcals from only “clean” foods.  This is where we can start to include “cheat meals”.  If a client is not gaining weight as a fast enough pace, then having one meal/week to cheat is often included.  This is a meal where nearly anything goes!  Usually for dinner (so the cheating doesn’t last all day) the athlete will eat whatever they want, as long as it’s calorically dense.  Favorites are usually pizza, ice-cream, candies etc…  I have found this to be a very effective strategy, and as long as it’s kept to only a single meal/week, excess fat gain is kept to a minimum.

How to build muscle for skinny guys - pizza

Also check out this Free diet plan for an ectomorph to gain muscle

Training recovery

The next thing to look at would be recovery from training, and the client’s ability to relax.  It is very hard for the body to grow when it is overly stressed.  Train hard will often help to increase appetite, which is great for the goal of weight-gain, but it is not un-common for an extremely motivated individual to train too hard, too often and for too long.  When this happens, not only are you burning extra calories, but you are increasing cortisol (a catabolic hormone) which in excess can rob you of muscle gains.  In some cases, training to the extreme will even lower appetite.  This is why I usually only recommend 4-5, intense, 1 hour resistant training sessions/week.  I highly recommend finding a good Strength and Conditioning Coach to write you a training program that aligns with your goals and abilities.  One should aim for at least 8 hours of sleep every night, as sleep is when you recover and grow from training.

As far as training for hypertrophy goes, it is important to keep the sessions short, but very dense.  This means trying to include the most amount of volume in to a time period as possible.  Rest between sets should be relatively short (30-90 seconds), reps should be high (6-20) while making sure that the eccentric (lowering of the weight) is emphasised.  Keeping the reps high, while slowing down the eccentric will mean that less weight will be on the bar, stack or dumbbell, but will ensure that the time-under-tension for the muscles being worked is high, which is the key to hypertrophy.  Another mistake I often see skinny guys making in the weight-rooms is constantly training smaller muscle groups, such as the arms, or abdominals.  There is a time and a place for this, but if one’s goal is primarily to gain weight and overall muscularity, using “bang for your buck” exercises will be most efficient.  Big movements like squats, bench presses, dips, chin/pull-ups, deadlifts etc… will train the most motor units and will lead to the biggest muscle and strength gains.

Here is a simple workout session focusing on chest and back for an intermediate trainee

A1:  Incline Barbell Press 6 (sets)/ 8-10 (reps) 5110 (5 seconds to lower, 1 second pause at the chest, 1 second to lift and no pause at the top)

Rest 60 seconds

A2:  Neutral Grip Chin-ups or Pull-downs 6/8-10 5011

B1:  Flat DB Neutral Grip Press 4/10-12 4010

Rest 45 Seconds

B2:   Bent over 1 Arm DB Row (bench supported) 4/10-12 4010

C1:  Push-ups 2/max reps 2010

Rest 30 Seconds

C2:  Inverted Row 2/max reps 2010


This entire session should take no longer than 1 hour, but due to the short rest breaks, paused reps, slow eccentrics and high overall reps, the TUT (time under tension) is extremely high and will create a great deal of mechanical damage used to signal hypertrophy.

Please leave any questions or comments you might have, and best of luck with achieving your goals!

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Pollyanna Hale Health and Lifestyle coaches
Lost 13 Kg in Total
Mel, 32y Location: London, United Kingdom Working with Pollyanna changed everything. I lost 13kg, got toned and have more energy than ever! Get same results!


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Lost 45 Kg in Total
Chris, 50y Location: London, United Kingdom Lost 45kg after the age of 50 and now competes and wins physique competitions and runs marathons Check our weight loss plans