A realistic plan to bulk up as a skinny guy: how much to eat, how fast to gain, how to train, and what to do when the scale will not move.
To bulk up as a skinny guy, eat about 300 to 500 calories above maintenance every day, get roughly 0.7 to 1 g of protein per lb of body weight, and aim to gain 0.5 to 1 lb per week. Train each muscle about twice a week with 10 to 20 hard sets, built around compound lifts, and add reps or weight every session you can. Sleep at least 7 hours. If your weekly average weight has not moved in two weeks, add another 200 calories.
If you have always been the thin one, "eat more and lift heavy" is advice you have heard a hundred times. It is not wrong. It is just missing the numbers, and without numbers most skinny guys either undereat for months and change nothing, or overcorrect, gain 25 lb in a summer, and end up softer instead of bigger.
This guide gives you the numbers: how much to eat, how fast the scale should move, how to train so the extra food turns into muscle, and how to fix things when progress stalls.
Faster than most people, at least at first. If you are new to serious weightlifting, your body responds to training more strongly than it ever will again. Still, muscle is built slowly. Even in a good first year, most beginners add somewhere in the range of 1 to 2 lb of actual muscle per month, and less after that.
The scale can move faster than that, because a surplus also adds water, glycogen, food in your gut, and some fat. A sensible target is about 0.25 to 0.5 percent of your body weight per week, which is the range a 2019 review of off-season bodybuilding nutrition by Iraki and colleagues suggested to limit fat gain.
| Body weight | 0.25% per week | 0.5% per week | Over 12 weeks |
|---|---|---|---|
| 130 lb | ~0.3 lb | ~0.65 lb | ~4 to 8 lb |
| 145 lb | ~0.35 lb | ~0.7 lb | ~4 to 9 lb |
| 160 lb | ~0.4 lb | ~0.8 lb | ~5 to 10 lb |
If you are very lean and a true beginner, you can lean toward the top of that range, or slightly above it, at around 1 lb a week. If you are gaining 2 lb or more every week after the first two, you are mostly adding fat.
Start with your maintenance calories: the amount that keeps your weight steady. A rough estimate is your body weight in pounds multiplied by 15 to 17, but the honest answer comes from tracking what you eat for a week or two while your weight stays flat.
Then add 300 to 500 calories a day. Slater and colleagues, in a 2019 review asking whether a surplus is needed to maximize muscle growth, landed on a modest daily surplus in roughly that range as a reasonable starting point. A bigger surplus mostly speeds up fat gain, not muscle gain. A study of elite athletes by Garthe and colleagues in 2013 found that a planned surplus produced more lean mass than eating freely, but also more fat.
For a 140 lb guy with a maintenance of about 2,300 calories, that means eating around 2,600 to 2,800 a day.
Most "hardgainers" eat big meals a few times a week and small, skipped meals the rest of the time. The total for the week ends up close to maintenance. Track a normal week before you decide your metabolism is the problem. It usually is not.
Aim for about 0.7 g per lb of body weight per day, and up to 1 g per lb if you want a margin. A 2018 meta-analysis by Morton and colleagues found the benefit of extra protein on muscle and strength gains levelled off around 0.7 g per lb. The International Society of Sports Nutrition's 2017 position stand recommends a similar range.
For a 140 lb lifter, that is about 100 to 140 g a day, spread across 3 to 5 meals. Protein matters, but on a bulk the bigger problem is usually total calories, so do not let a high protein target crowd out the rest of your food.
Food gives your body the materials. Training is the signal that tells it to build muscle instead of storing fat. Without a strong, progressive signal, a surplus mostly makes you heavier.
A 2016 meta-analysis by Schoenfeld and colleagues found that training a muscle at least twice a week produced more growth than once a week. A simple upper/lower split, four days a week, does this well.
A 2017 meta-analysis by Schoenfeld, Ogborn, and Krieger found more weekly sets led to more growth, with 10 or more sets per muscle per week doing better than fewer. Start around 10 to 12 hard sets per muscle per week and build toward 15 to 20 if you recover well.
Squats, deadlifts or Romanian deadlifts, bench press, overhead press, rows, and pull-ups train a lot of muscle per set. Add a few isolation exercises for arms, shoulders, and calves once the basics are in place.
This is where most bulks quietly fail. If you are eating 500 extra calories a day and benching the same 135 for the same 3 sets of 8 for two months, the extra food has nowhere useful to go. Use double progression: pick a rep range, add reps each session, and add weight once you hit the top of the range on every set with a rep or so left in reserve.
| Week | Bench press | What happened |
|---|---|---|
| 1 | 135 lb × 8, 8, 7 | Inside the range of 6 to 10 |
| 2 | 135 lb × 9, 8, 8 | Add reps |
| 3 | 135 lb × 10, 9, 9 | Add reps |
| 4 | 135 lb × 10, 10, 10 | Top of the range: add weight |
| 5 | 140 lb × 8, 7, 7 | Start climbing again |
You do not need special foods. You need more food, and food that is easy to eat in quantity. Our list of the best bulking foods gives USDA calorie and protein numbers for each one.
At least 7 hours a night, which is the minimum the American Academy of Sleep Medicine and Sleep Research Society recommend for adults. Short sleep makes hard training feel harder, makes it easier to miss sessions, and can blunt recovery. If you are training hard, eating enough, and sleeping 5 hours, sleep is the cheapest fix available.
Weigh yourself first thing in the morning, most days, and look at the weekly average rather than any single day. Then use this simple rule:
Expect a jump of 2 to 3 lb in the first week or two as your body stores more water and glycogen. That is normal and not fat.
Alexandros is an iPhone app that works like a personal weightlifting coach you talk to in a chat. It does not track your food, so the eating side of a bulk is on you. It handles the other half: making sure the training signal keeps getting stronger.
You log a session in plain English, like "bench 135 for 3 sets of 10, last set was hard," and it turns that into structured sets with an effort rating. Every recommendation uses double progression through a rep range set by your goal, so with a goal of building muscle it climbs your compound lifts through 6 to 10 reps and adds weight when you reach the top with a rep to spare. If a lift stalls for three sessions in a row, it plans a deload. Ask "How has my squat progressed?" and you get a chart of top weight, estimated one-rep max, and volume from your own log, which is exactly what you want to see on a bulk.
You will gain some fat, but you can keep it small. A surplus of 300 to 500 calories, a gain rate of about 0.25 to 0.5 percent of body weight per week, and training that keeps progressing will put most of the new weight into muscle and stored glycogen.
Usually not. Eating anything and everything in a large surplus speeds up weight gain, but the extra speed is mostly fat. A moderate surplus built mostly from regular meals gets you nearly the same muscle with far less to diet off later.
Most people do well with at least 4 to 6 months, and very skinny beginners can bulk for a year or more. Stop when you are carrying more fat than you are comfortable with, or when your weekly gain keeps outpacing your strength gains.
No. Mass gainers are mostly sugar and protein powder. A homemade shake with milk, oats, peanut butter, and fruit does the same job, usually for less money.
A little is fine and good for your health. Two or three easy sessions a week will not stop you gaining, though you may need to eat slightly more to cover them. Avoid hard conditioning that leaves you too tired to train well. Our guide on cardio while bulking covers the research in detail.
