Most clients come to you with the goal of losing weight. So unless you train athletes, most of your training programs and nutrition advice will focus on helping those clients reduce body fat.

That’s why it’s exciting for me when a new client tells me his number-one goal is to gain weight. It’s a goal I can certainly relate to. Eight years ago, when I finished high school, I weighed just 128 pounds at my current height of five-foot-10.

My goal was to compete in bodybuilding. Someone else might want to bulk up for a specific sport, or just to feel better about himself when he looks in the mirror. (I use the male pronoun because I’ve never had a female client ask me to help her get bigger. Stronger, yes, but not heavier.)

What they all have in common, in my experience, is that they’ve already tried to do it on their own, with disappointing results. Either they failed to gain weight at all, or they gained so much fat they looked and felt worse.

Again, I can relate. At one point, in a quest to reach 200 pounds, I looked more like the Michelin Man than a personal trainer with bodybuilding goals.

That’s why I always start by explaining why the process is so frustrating.

What to Expect When You’re Expecting to Gain Weight

First, and most important, is this:

Unless the client is a beginner, has freaky genetics, or takes anabolic drugs, muscle building is a slow process. 

In Lean Muscle Diet, nutritionist Alan Aragon says these are reasonable rates of muscle gain with minimal increases in body fat:


Client Category

Potential Rate of Muscle Growth

Novice (less than 2 years of consistent strength training) 2-3 lbs. per month
Intermediate (2-4 years of consistent training) 1-2 lbs. per month
Advanced (close to their genetic ceiling) 1/2 lb. per month


Obviously, this isn’t what your clients see in bodybuilding articles and supplement ads. To put the disappointment in context, I like to tell new clients about the time I sat down with my own coach to draw up a long-term plan.

“Let’s aim for five to six pounds of quality weight gain,” he told me.

“Per year, I assume?”

“No,” he said, “that’s for three years.”

If nothing else, it makes the addition of two to three pounds a month sound a lot more exciting.

The Questions You Have to Ask

Let’s say the client is a genetically average-looking guy in his 20s or early 30s who, you estimate, has body fat of 15 to 20 percent. Your first question:

“Do you want to gain weight? Or do you want the illusion of looking bigger?”

More often than not, it’s the latter. If you’ve ever helped a client like this through a transformation, you’ve probably seen that even after losing 10 to 20 pounds, he appears bigger and more muscular.

So if that’s his goal, he’s better served by a fat-loss program that includes a calorie deficit.

Now, if the client isn’t sure, or is dead-set on gaining weight, you need to help him understand the basic science of body composition. As Dr. Gilbert Forbes explained in this study back in 2000, the majority of weight a lean person gains will be muscle, while a person with obesity will add more fat.

In other words, the more fat you start with, the more you’ll gain. (It’s the opposite for weight loss; a lean person will lose a higher percentage of muscle.)

Nobody can predict exactly what will happen for any specific client, but you have to make sure he understands that any weight he gains will include some percentage of fat.

I can usually convince a client like this to eat at maintenance or a slight deficit for the first four to eight weeks of training, with the goal of “priming” his body to gain a higher percentage of lean mass over the next few months.

Here’s how I sell the benefits of a priming phase:

  • If the client is a complete beginner, or hasn’t been on a structured plan before, he’ll probably gain some muscle and lose some fat simultaneously.
  • Even if he doesn’t gain much muscle, he’s still building a solid base for future gains.
  • I can pretty much guarantee he’ll like his leaner appearance, and encourage him to take “before” pictures so he’ll be able to see how much progress he’s made when he takes “after” photos a few weeks later.

But what if the client is already lean? In that case, you have to ask a different by equally important question:

“Are you willing to let your abs go, at least during your weight-gain phase?”

If the answer is no, that they want to stay lean, then you have to explain that their gains will be much slower than they expected.

A new client who’s always been skinny will be fine with losing his abs, in my experience, while a long-term client who’s worked hard for years to get lean will choose to go slower.

The reason is pretty simple: We all tend to value most what we found hardest to achieve. Thus, a never-fat guy will value size over definition, while a guy who struggled to get his abs will want to keep them.

Now it’s time to talk about diet and training, both of which are much simpler and more straightforward when the client knows what to expect.

The Overeater’s Diet

A weight-gaining diet has to meet two goals:

  • Sufficient calories and nutrients to fuel exercise and support recovery.
  • Surplus calories to build new lean tissue.

For most clients, 18 to 20 calories per pound of body weight per day is a good starting point, with these macronutrient guidelines:

  • Protein: one gram per pound of body weight
  • Fat: 20 to 30 percent of total calories
  • Carbs: 50 to 60 percent of total calories

If your client weighs 175 pounds, his diet would look something like this:

  • 3,150 calories (18 calories per pound)
  • 175 grams of protein
  • 85 grams of fat (about 25 percent of calories)
  • 420 grams of carbs (about 53 percent of calories)

Why so much carbohydrate? Building muscle requires a lot of fuel for training, and a lot of nutrients for recovery.

Plus, foods loaded with starchy carbs, like rice, are the easiest to eat in massive quantities. That’s why you tell clients to reduce them when they’re trying to lose weight. To gain weight, you want the most calorie-dense and hyper-palatable foods.

In other words, you want your clients do the opposite of everything in this weight-loss article.

I also recommend alternating whole-food meals with protein shakes. So in between breakfast and lunch, and lunch and dinner, he’d have a shake with 30 grams of whey protein, three-fourths cup of oats, and a tablespoon of peanut butter.

I try that for two weeks, see how the client responds, and adjust accordingly.

Gaining too fast? We reduce calories slightly.

Not gaining, or even losing? Add an extra 150 to 300 calories.

If your client is an athlete who’s in good shape and training hard, you’ll probably need to increase these numbers. But it’s always better to start low and add food, rather than overshoot and be forced to cut back.

The Base-Building Workout

My training programs are based on two core principles:

  • Progressive overload
  • Perfect form

I apply these principles with all my clients, whether they’re trying to gain muscle or lose fat. My reason is simple: If you don’t give your body a new stimulus, it’ll stay the same. A body that stays the same will look the same.

But progression only works if you can maintain perfect form. Otherwise, you’re risking injury.

My programs follow these general parameters:

  • We do three to four workouts a week.
  • About 80 percent of the training is focused on big, compound exercises.
  • Most sets are six to 12 reps.
  • We train each muscle group at least twice per week.
  • We keep volume low to moderate, with 12 to 18 sets per workout.
  • Each program lasts at least 12 weeks; program hopping never works.
  • We take relatively few sets to failure.

That last point requires a little explanation. As James Krieger pointed out in his hypertrophy article, you need to train to failure to maximize muscle growth.

I don’t dispute that. Failure training has its place, and I’ll certainly use it from time to time.

But remember that our goal here is to build strength steadily over time, without ever compromising form. A bigger body requires a bigger base, which we have to build from the inside out. Muscles can get bigger in a matter of weeks, but tendons and ligaments need more time to add new contractile tissue. It usually takes even longer to see measurable increases in bone mineral density.

There’s no risk that the client won’t gain muscle on a program like this. We know that strength gains in moderate rep ranges will translate to new lean mass over time.

Plus, by not training to failure on most sets, muscles will recover faster from workout to workout, which supports our primary goal of increasing strength.

READ ALSO: How to Measure and Improve Muscle Strength

How to Track Progress

With fat-loss clients, you have simple and straightforward ways to measure results—scale, tape measure, calipers. The faster you get those results, the happier your client will be.

But, as we’ve established, muscle building is a slower process. A client who gains weight fast probably won’t like the results. I know I didn’t. That’s why we use performance as our number-one indicator of progress.

Specifically, we track performance on a handful of indicator lifts. For each lift, we’ll establish a goal to reach in the next eight to 12 weeks.

The specific lifts are different for each client, based on three criteria:

  • They suit the client’s mechanics. For example, if someone has unusually long arms, we don’t use the bench press as an indicator lift.
  • They’re pain-free.
  • They allow the client to maintain tension on the right muscles with increasingly heavy loads.

For online clients, I ask them to shoot video of their top sets on their indicator lifts. I do that because it helps me track their form, and also helps make them more aware of their own form, since they know I’ll see and comment on it.

I also use photos to track progress. I ask my online clients to take “before” pictures in their boxers from the front, back, and side, and then take a new set every three to four weeks. Again, this relates to my own experience trying to reach 200 pounds. Because I was getting stronger on a weekly basis, it was easy to convince myself that every new pound I gained must be muscle.

When I finally took pictures and sent them to my coach, I got a rude awakening. It wasn’t all muscle.

In addition to performance measures and photos—and, obviously, scale weight—I also like my online clients to track their waist circumference.

For in-person clients, I like to use all those along with calipers to monitor body composition. I find the most useful skinfold sites are the umbilical, suprailiac, subscapularis, and quadriceps.

Final Thoughts

If you take away nothing else from this article about training clients whose goal is to gain weight, I hope you’ll remember these two key points:

1. You need multiple tracking methods.

All these measures matter:

  • Exercise performance and form
  • Scale weight
  • Waist size
  • Appearance, using before-and-after pictures
  • Body fat, if possible

2. You need to remind your client that muscle building is a marathon, not a sprint.

Patience is a tough sell. As every trainer knows, we live in an age of instant gratification. There’s always someone willing to take advantage of your client’s impatience and distractibility by offering a better, faster solution.

That’s why emphasizing performance from day one helps your client stay focused on the plan. In my experience, every client enjoys seeing their strength increase, but I think it’s especially true for a guy who wants to get bigger.

When his patience starts to flag, I like to remind him of my own story:

Back in 2017, in my quest to hit 200 pounds, I peaked at a fluffy, aesthetically unsatisfying 198. I subsequently shifted gears and lost the excess fat. This year I got even closer, reaching 199 in much better condition. But even then, I had more fat than I’m comfortable with, and I’m now a few pounds lighter.

My point here?

Make sure your client understands what he’s in for. Because even when you do everything right, it can still end up looking wrong.