The 5 biggest mistakes skinny guys make when bulking up
Written by Martin Ebner
Updated Sept 2026
If you’re eating more and training hard but still look much the same, it’s tempting to assume you need a more extreme bulk. More meals, more sessions, more exercises and more supplements.
Usually, that’s not the answer.
In 15 years of coaching, I‘ve seen many attempted bulks repeat the same mistakes. Food is being guessed. The scale is being forced. Training feels hard but doesn’t progress. The program changes before it can work and recovery isn’t prioritised.
None of that means your genetics are broken.
“Skinny guy” and “hardgainer” are useful descriptions, not medical body types. They tell me where you’re starting and what you find difficult. They do not decide what you are capable of building.
1. YOU’RE GUESSING HOW MUCH YOU EAT
People who struggle to gain weight often feel as though they eat constantly. They may be right on some days. The problem is that one enormous dinner doesn’t tell you what happened across the week.
A missed breakfast, a light lunch and an active afternoon can quietly cancel it out.
Record seven typical days of food, including the weekend. You don’t need perfect measurements. You’re looking for missing meals, wildly different portion sizes and long stretches when very little is being eaten.
Weigh yourself on at least three mornings during the same week, after the loo and before breakfast. Use the average rather than reacting to a single number.
If your average weight has been stable for several weeks, your current food intake is roughly maintaining it. Add one repeatable meal, snack or portion increase. Somewhere around 200 to 300 additional calories is a sensible first experiment for many people.
That could be:
Greek yoghurt, granola and a banana
A sandwich and a glass of milk
More rice and olive oil with dinner
Oats, fruit and protein blended into a shake
Keep everything else reasonably steady for two or three weeks, then check the average again.
My macro guide for bulking explains how to do this without turning every meal into a maths exam.
You don’t need to track food forever. A short record is often enough to show you where the problem is. If tracking makes you anxious or rigid around food, use repeatable meals and measured portion changes instead.
2. YOU’RE TRYING TO MAKE THE SCALE MOVE TOO QUICKLY
Bulking is not a competition to gain weight.
A larger calorie surplus can make the scale rise faster, but it cannot force muscle to grow at the same speed. Beyond a point, you are mainly accelerating fat gain.
That doesn’t mean you must avoid gaining any fat. Some is normal and should be expected during a successful bulk. The aim is to keep it proportionate to the muscle and strength you’re building.
Use three indicators together:
Your average bodyweight
Your waist measurement
Your training log
If bodyweight is rising gradually and your gym performance is improving, leave the food alone.
If bodyweight and performance remain flat after two or three consistent weeks, add roughly another 200 to 300 calories per day.
If your waistline is growing but your training isn’t, remove a small amount. Don’t slash the whole diet because one fortnight got away from you.
Protein matters, but more is not endlessly better. Roughly 1.6 to 2 grams per kilo of bodyweight is a useful daily reference for someone lifting weights. Once you’re around that amount, additional calories can come mainly from carbohydrate and fat.
You do not need a “dirty bulk”, an ectomorph diet or a cupboard full of mass-gainer powder. You need enough normal food, repeated consistently.
If appetite is the problem, use a few of these high calorie foods for skinny guys. Add them to meals you already eat rather than attempting six completely new meals on Monday.
3. YOU’RE TRAINING HARD WITHOUT PROGRESSION
A workout can be exhausting without being productive.
Sweating, soreness and passing out on the floor afterwards tell you that the session was difficult. They do not tell you whether it gave your body a better reason to build muscle than last week.
Write down your exercises, sets, repetitions and weights. You don’t need an elaborate app. Notes on your phone will do.
Give each exercise a sensible repetition range. If you perform three sets of eight repetitions this week, try to earn another repetition somewhere next time. When you can reach the top of the range with good control, add a small amount of weight and begin again.
Progress can mean:
More repetitions with the same weight
A little more weight for the same repetitions
Better control and range of movement
The same work completed with less rest
More useful work without losing form
It does not mean adding weight at any cost.
Train all the major muscle groups, legs included, across a schedule you can genuinely maintain. For many people, two or three well-built full-body sessions each week are enough to make progress. More sessions can work, but they aren’t automatically better.
Compound and isolation exercises are both useful. A squat is not morally superior to a leg extension, and a bench press is not compulsory if it irritates your shoulders. Choose exercises that train the intended muscles, suit your body and allow you to progress safely.
For every exercise that isn’t right for you, there are several others that can do the job.
4. YOU CHANGE THE PROGRAM BEFORE IT CAN RESPOND
Constant variety feels productive because every session is new. It also makes progress difficult to measure.
If the exercises, order and repetition ranges change every week, you never discover whether you are getting stronger at anything. You simply become experienced at starting again.
Keep the main structure of your program stable for several weeks. That gives you enough repeated practice to improve your technique and enough information to judge whether the plan is working.
Reasons to change an exercise:
It causes pain
It doesn’t suit your body
You cannot perform it with the equipment available
It consistently fails to train the intended area
Your goal or circumstances have genuinely changed
Boredom after two sessions is not a programming emergency.
Before abandoning a plan, check whether you actually followed it. Look at attendance, food, sleep and the training log. If several things changed at once, you won’t know which one mattered.
When an adjustment is needed, make one. Keep the rest steady and see what happens.
5. YOU’RE TRAINING MORE THAN YOU CAN RECOVER FROM
Training provides the reason to adapt. Recovery gives your body that opportunity.
Adding another gym session is not always the answer to slow progress. Sometimes it’s the reason progress has slowed.
Aim for a sleep routine that gives you roughly seven to nine hours most nights. You’ll survive an occasional short night, but consistently poor sleep makes hard training impossible to recover from.
Rest days are part of the program. They are not evidence that you lack commitment.
Cardio is not automatically stealing your muscle either. Walking, cycling, running and sport can remain part of a bulk. They support your health, and enjoying your life still matters.
You need to account for the energy they use. A large amount of hard endurance work can also leave your legs tired for resistance training. If that happens, separate the hardest sessions where practical, reduce the amount slightly or eat more to support it.
Removing every activity except lifting is rarely necessary.
Pay attention when several warning signs appear together: your performance keeps falling, soreness never clears, your joints are becoming irritated, sleep is deteriorating or you dread sessions you normally enjoy.
One poor workout means very little. A repeated downward trend deserves a response. Reduce the training volume for a week, keep your food reasonably steady and see whether performance returns.
WHAT A GOOD BULK LOOKS LIKE
A good bulk is more ordinary than the marketing makes it sound.
You eat a similar structure most days. Your weight moves upwards slowly. Your training log improves and the plan fits around the rest of your life well enough to maintain it consistently.
Some weeks will be flat. Some exercises will stall before others. That’s normal.
If you are starting now:
Record seven ordinary days of food.
Take at least three morning weights and calculate the average.
Add one repeatable meal, snack or portion increase if your weight is stable.
Follow a consistent program that trains all the major muscle groups.
Record your exercises.
Review the results after two or three weeks.
Change one thing at a time.
My hardgainer workout and diet guide puts the food and training together in one place.
I write more about training, nutrition and health in Check It Oot, my bi-weekly newsletter.
Cheers, Martin
