Most skinny guys are skinny because they don’t eat enough good-quality food.
If you are skinny and you want to bulk up, stop complaining about your “metabolism” and start raiding the ‘fridge like a hungry Viking.

It’s simple. To gain muscle mass, you must gain body weight. Unless you are gaining a pound of body weight every week, weight lifting will serve only to wear you out. Think of how frustrated Sisyphus got, pushing his boulder up the hill, over and over again. If you are undernourished, your workouts are akin to Sisyphus’ futile efforts on the hill. Don’t let Zeus get the last laugh; eat well and grow bigger.
Once you start gaining weight steadily with a good-quality bulking diet, while simultaneously lifting heavier and heavier weights on a lifting program that features progressive overload, you will begin to add muscle mass.
Things to keep in mind about a bulking diet
Without getting too clinical in your approach to designing a bulking diet, remember a few key points:
- Slow carbs are better at all times of the day except in the time surrounding a workout
- Get serum amino acid concentrations up immediately after the workout (1/2-hour time window after lifting)
- Get some fast carbs immediately after working out to fuel protein synthesis
- Working out hard may shut down your digestion – Research shows an 80% reduction in blood flow to the digestive tract after an hour of hard exercise in horses. In humans, it’s not clear that this is the case; recent evidence shows that it may not be the case for humans
- Small meal rather than large meal before working out to try to lessen the chance of experiencing heartburn (esophageal reflux)
- Wait an hour after eating a meal to exercise
- Both exercise and dehydration delay stomach emptying – so post-workout fast carbs and fast protein are essential. (Some research shows that a post-workout carb/protein meal is not digested quickly enough to be available during the anabolic window)
- Take time to eat, don’t bolt your meals. Chewing plays a major role in digestion.
- Slow protein before bed
- Reduce carbs before bed, especially if fat accumulation is a concern
- Use the guidelines in the How to design a bulking diet article to estimate your ideal macronutrient ratio
- Try to eat “good” fats (monounsaturated fat), even while bulking
- Get enough dietary fiber, especially since dietary protein levels are extremely high

Sample bulking diet
For the sample bulking diet, I will assume a 150 pound (68 kg) man that’s 5′8″ (172 cm) in height and lean at an age of 25 years.
Use this four-step process to estimate the parameters of the bulking diet:
- Use the Harris-Benedict equation, or something similar, to estimate maintenance level of calories on a bulking routine, then add 500 calories per day
- Second, calculate how much protein to eat
- Third, calculate how much fat to eat
- Round it off with Carbs
Step 1:
Weight in pounds multiplied by 6.23 is: 150*6.23=935
Age in years multiplied by 6.8 is: 25*6.8=170
Height in inches multiplied by 12.7 is: 68*12.7=864
Sum these subtotals to estimate your basal metabolic rate:
BMR = 935+170+864 = 1969
Add in a factor for “moderate exercise” which is 1.55 times the BMR:
1969*1.55 = 3052
Therefore, 3052 is the maintenance level of calories that we have estimated.
Add 500 calories per day to this maintenance level:
3052+500 = 3552
Therefore 3552 calories per day is the number of calories we’ll eat on our bulking diet.
Keep track of weight and after a month, adjust this calorie amount up or down according to the trend. Make further adjustments every 2 weeks.
Step 2:
You want at least 20% of your energy to come from protein.
3552*.20=710 calories supplied by dietary protein.
Every gram of protein supplies 4 calories:
710/4= 178 grams of protein per day
This is equivalent to 1.2 grams of protein per pound of body weight per day. This is undoubtedly excessive, but in today’s climate of protein-obsessed bodybuilders, I’m bowing to peer pressure and accepting this for a bulking diet. Less protein is probably fine.
Step 3:
I want 30% of my energy to come from fat, with as little saturated and polyunsaturated fat as possible.
3552*.30=1066 calories per day from fat
At 9 calories per gram:
1066/9= 118 grams of fat per day
Step 4:
Remainder of the bulking diet takes the form of carbs, including dietary fiber.
3552-(fat calories)-(protein calories):
3552-1066-710 = 1776 calories per day from carbohydrates
The sample bulking diet for a skinny man
The sample diet will consist of five meals and a glass of chocolate milk as a post-workout snack. In accordance with our calculations above, it will supply:
- approximately 3500 calories
- 50 grams of dietary fiber
- a huge amount of dietary protein
- a relatively healthy ratio of “good” to “bad” dietary fats
Following each meal is the relevant nutritional information and a pie chart displaying the macronutrient ratio as a function of calories. The use of a nutritional tracking program or online service makes it easy to see if your diet is delivering the nutrients you need. Make adjustments as necessary to get the results you want. Without good data, you have to rely on blind luck, which is a fool’s gamble.
|
Calories |
Fat (g) |
Carbs (g) |
Protein (g) |
|
| BREAKFAST | ||||
| Oatmeal, made with milk, 2 cups |
472 |
13 |
66 |
25 |
| Omelet, 2 whole eggs and 2 egg whites |
201 |
14 |
1 |
16 |

| BRUNCH | ||||
| Can of tuna, packed in water – 3 ounces |
99 |
1 |
0 |
22 |
| 4 slices of whole-wheat bread |
315 |
5 |
59 |
12 |
| 2 tablespoons of mayonnaise |
198 |
22 |
1 |
0 |

| LUNCH | ||||
| Artichoke hearts, in olive oil – 4 hearts (8 halves) |
133 |
9 |
11 |
4 |
| Medium chicken breast, fried |
425 |
18 |
0 |
63 |
| Barbeque sauce, 1 ounce |
21 |
1 |
4 |
1 |
| Roasted almonds – 20 almonds or 1 ounce |
172 |
16 |
5 |
6 |

| AFTERNOON (at least 1 hour before working out) | ||||
| 1 can smoked oysters or clams in oil (3.75 ounce) |
186 |
12 |
3 |
15 |
| 1 cup shredded romaine lettuce |
8 |
0 |
1 |
1 |
| Medium carrot |
26 |
0 |
6 |
1 |
| Celery, medium stalk |
6 |
0 |
1 |
0 |
| Whole milk – 8 ounces |
149 |
8 |
11 |
8 |

| AFTER WORKOUT (immediately after lifting) | ||||
| Chocolate milk |
207 |
8 |
26 |
8 |

| DINNER | ||||
| Chili with kidney beans, beef, tomato – 2 cups |
641 |
28 |
54 |
45 |
| 1 cup string beans cooked |
83 |
4 |
11 |
3 |
| 1 cup brown rice |
170 |
4 |
30 |
4 |

| DAILY TOTALS |
3512 |
163 |
290 |
234 |
|
Calories |
Fat (g) |
Carbs (g) |
Protein(g) |
Bulking diets are not complicated
As you can see, it’s possible to get a sufficient number of calories without resorting to weight gainer shakes and similar contrivances. Also, while protein powder is undoubtedly convenient, you can easily get more than enough protein in your diet without it. If you want, use protein powder during time-critical periods like immediately after a workout, but always remember that good, natural food is the cornerstone of a successful bulking diet.
As is, the sample diet provides 40% of the daily energy in the form of dietary fat. This may be excessive for everyday consumption, but for bulking, you have to get your calories where you can, and fat is one of the easiest ways to increase your caloric total. If you want to keep your daily fat intake under 30% of your total calories, remove the excess mayonnaise and oil and replace it with fresh salsa or something similar, then increase your portions.
Of inestimable importance is the act of keeping records. If you don’t know where you have been, you won’t be able to predict where you are going. Equip yourself with whatever you need to track your diet – an Excel spreadsheet, a nutrition-tracking program, an online service – and diligently record the various data. Without accurate records, you will fail. With records, you can easily adjust your diet.
The bulking diet used by a skinny guy doesn’t have to be complicated. As long as your caloric needs are being met and exceeded, you will gain weight. Lift hard and always aim to increase your levels of strength, and a good portion of your weight gain will come in the form of quality muscle mass.